CN112525950A - Method for measuring heat exchange energy of radiation refrigeration material and electronic device - Google Patents
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Abstract
The application relates to a method for measuring heat exchange energy of a radiation refrigeration material, an electronic device and a storage medium, wherein the method comprises the following steps: measuring the environmental temperature to obtain the surface temperature of the material to be measured; respectively calculating a first proportion value of atmosphere and a second proportion value of the material according to the ambient temperature and the surface temperature of the material; respectively calculating a first weighted emissivity of the atmosphere and a second weighted emissivity of the material according to the spectral emissivity of the atmosphere and the material; respectively calculating the absorption energy and the radiation energy of the material according to the first proportion value, the second proportion value, the first weighted emissivity, the second weighted emissivity, the environment temperature and the surface temperature of the material; according to the method and the device, the heat exchange energy of the radiation refrigeration material is determined according to the absorption energy and the radiation energy, the problems that a large amount of time is needed and the process of determining the quality of the radiation cooling effect is inaccurate are solved, and the heat exchange energy of the radiation refrigeration material is rapidly and accurately measured.
Description
Technical Field
The application relates to the technical field of measurement, in particular to a method for measuring heat exchange energy of a radiation refrigeration material and an electronic device.
Background
The radiation refrigeration material has the characteristic of reducing the temperature of the material without consuming energy, and is widely applied to the fields of energy-saving building materials, outdoor products and the like. The radiation heat exchange energy is one of indexes for measuring the cooling capacity of the material, and the size of the radiation heat exchange energy is directly related to the quality of the radiation cooling effect of the product. The size of the radiation heat exchange energy of the radiation refrigeration material is obtained through a large number of iterative calculations, and a large amount of time is needed in the process of obtaining the radiation heat exchange energy through the method.
At present, under the condition of consistent solar absorption rate, a simplified method based on sky temperature is generally adopted to obtain the size of radiation heat exchange energy, although the method reduces the calculated amount to a certain extent, the calculated result of the size of the radiation heat exchange energy is inaccurate because the wave band characteristics of an atmospheric window and the heat exchange condition of a radiation refrigeration material are not reflected.
At present, an effective solution is not provided aiming at the problems that a large amount of time is needed and inaccurate in the process of determining the good and bad radiation cooling effect in the related art.
Disclosure of Invention
The embodiment of the application provides a method for measuring heat exchange energy of a radiation refrigeration material, an electronic device and a storage medium, so as to solve the problems that a large amount of time is needed and inaccuracy is needed in the process of determining the quality of a radiation cooling effect in the related art.
In a first aspect, an embodiment of the present application provides a method for measuring heat exchange energy of a radiation refrigeration material, including:
measuring the ambient temperature to obtain the material surface temperature of the radiation refrigeration material to be measured;
respectively calculating a first ratio value of radiation energy of the atmosphere, which is radiated outwards by infrared rays of a first wave band, a second wave band and a third wave band, to the total radiation energy of the atmosphere according to the ambient temperature, and respectively calculating a second ratio value of radiation energy of the radiation refrigeration material, which is radiated outwards by infrared rays of the first wave band, the second wave band and the third wave band, to the total radiation energy of the radiation refrigeration material according to the surface temperature of the material, wherein the wave bands of the infrared rays are divided into the first wave band, the second wave band and the third wave band from small to large, and the second wave band is a wave band where an infrared radiation atmosphere window is located;
respectively calculating first weighted emissivity of the atmosphere to infrared rays of a first waveband, a second waveband and a third waveband according to the spectral emissivity of the atmosphere under each waveband, and respectively calculating second weighted emissivity of the radiation refrigeration material to infrared rays of the first waveband, the second waveband and the third waveband according to the spectral emissivity of the radiation refrigeration material under each waveband;
calculating the absorption energy of the radiation refrigeration material from the atmosphere through infrared rays of a first wave band, a second wave band and a third wave band according to the first proportion value, the first weighted emissivity, the second weighted emissivity and the ambient temperature, and calculating the radiation energy of the radiation refrigeration material radiated to the atmosphere through infrared rays of the first wave band, the second wave band and the third wave band according to a second proportion value, the second weighted emissivity and the surface temperature of the material;
and determining the heat exchange energy of the radiation refrigeration material according to the absorption energy and the radiation energy.
In some embodiments, calculating a first ratio of the radiation energy of the atmosphere radiated outward by the infrared rays of the first, second, and third wavelength bands to the total radiation energy of the atmosphere according to the ambient temperature includes:
according to the relationship among the ambient temperature, the wavelength in the infrared band and the radiation force of the atmosphere and the wavelength, the radiation energy of the atmosphere radiated outwards by the infrared rays of the first band, the second band and the third band is calculated respectively, according to the relationship among the ambient temperature, the ambient temperature and the radiation force of the atmosphere, the total radiation energy of the atmosphere is calculated, and according to the radiation energy of the atmosphere radiated outwards by the infrared rays of the first band, the second band and the third band and the total radiation energy of the atmosphere, a first proportion value of the radiation energy of the atmosphere radiated outwards by the infrared rays of the first band, the second band and the third band to the total radiation energy of the atmosphere is obtained.
In some embodiments, calculating a second ratio of the radiation energy of the radiation refrigeration material radiated outward by the infrared rays of the first wavelength band, the second wavelength band and the third wavelength band to the total radiation energy of the radiation refrigeration material according to the material surface temperature includes:
according to the relationship among the material surface temperature, the wavelength in the infrared band and the radiation force of the material and the wavelength, the radiation energy of the radiation refrigeration material radiated outwards by infrared rays of a first band, a second band and a third band is calculated respectively, according to the relationship among the material surface temperature, the material surface temperature and the radiation force of the material, the total radiation energy of the radiation refrigeration material is calculated, and according to the radiation energy of the radiation refrigeration material radiated outwards by infrared rays of the first band, the second band and the third band and the total radiation energy of the radiation refrigeration material, a second proportion value of the radiation energy of the radiation refrigeration material radiated outwards by infrared rays of the first band, the second band and the third band to the total radiation energy of the radiation refrigeration material is obtained.
In some embodiments, calculating the first weighted emissivity of the atmosphere to the infrared rays of the first, second and third wavelength bands respectively according to the spectral emissivity of the atmosphere at each wavelength band comprises:
and respectively calculating first weighted emissivity of the atmosphere to infrared rays of a first waveband, a second waveband and a third waveband according to the relationship among the ambient temperature, the spectral emissivity of the atmosphere under each waveband, the wavelength in the infrared waveband and the radiation power of the atmosphere and the wavelength.
In some embodiments, calculating the second weighted emissivity of the radiant cooling material for the infrared light of the first, second, and third wavelength bands separately from the spectral emissivity of the radiant cooling material at each wavelength band comprises:
and respectively calculating second weighted emissivity of the radiation refrigeration material to infrared rays of the first waveband, the second waveband and the third waveband according to the relationship among the surface temperature of the material, the spectral emissivity of the radiation refrigeration material under each waveband, the wavelength in the infrared waveband and the radiation force of the atmosphere and the wavelength.
In some of these embodiments, determining the heat exchange energy of the radiant refrigeration material from the absorbed energy and the radiant energy comprises:
determining the total absorption energy absorbed from the atmosphere according to the absorption energy absorbed from the atmosphere by the infrared rays of the first wave band, the second wave band and the third wave band, determining the total radiation energy radiated to the atmosphere by the radiation refrigeration material according to the radiation energy radiated to the atmosphere by the infrared rays of the first wave band, the second wave band and the third wave band, and determining the heat exchange energy of the radiation refrigeration material according to the total absorption energy and the total radiation energy.
In some of these embodiments, the method further comprises:
measuring the solar absorptivity, solar radiation intensity and convective heat transfer coefficient of the material;
calculating solar radiation energy absorbed by the radiation refrigeration material according to the solar absorptivity and the solar radiation, and calculating energy transmitted to the radiation refrigeration material from the outside through thermal convection according to the surface temperature of the material, the ambient temperature and the convection heat transfer coefficient;
and determining the net radiation refrigeration power of the radiation refrigeration material according to the absorbed energy, the radiation energy, the solar radiation energy absorbed by the radiation refrigeration material and the energy transmitted to the radiation refrigeration material through the heat convection outside.
In some of these embodiments, obtaining the material surface temperature of the radiant refrigerant material to be measured comprises:
measuring the heat conductivity coefficient, the thickness and the lower layer temperature of the radiation refrigeration material, the solar absorptivity and the solar irradiation intensity of the material, and obtaining a third proportional value of the convective heat transfer coefficient and the surface temperature of the material;
when the energy balance of the outer surface of the radiation refrigeration material is achieved, the material surface temperature of the radiation refrigeration material is calculated according to the heat conduction coefficient of the radiation refrigeration material, the material thickness, the material lower layer temperature, the solar absorptivity of the material, the solar irradiation, the convective heat transfer coefficient, the environment temperature, the first weighted emissivity, the second weighted emissivity, the first proportional value and the third proportional value.
In some of these embodiments, obtaining the third ratio value includes:
respectively calculating a third proportion value of radiation energy of the radiation refrigeration material, which is radiated outwards by infrared rays of a first wave band, a second wave band and a third wave band, in the common temperature range of the earth surface, in the total radiation energy of the radiation refrigeration material, and determining the relation between the third proportion value and the surface temperature of the material, wherein the common temperature range comprises 250-320K;
and acquiring a first preset value, and acquiring a third proportion value under the surface temperature of the material according to the first preset value and the relation between the third proportion value and the surface temperature of the material.
In a second aspect, the present application provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for measuring heat exchange energy of a radiation refrigeration material according to the first aspect.
In a third aspect, the present application provides a storage medium, on which a computer program is stored, where the program is executed by a processor to implement the method for measuring heat exchange energy of a radiation refrigeration material as described in the first aspect.
Compared with the related art, the method for measuring the heat exchange energy of the radiation refrigeration material, the electronic device and the storage medium provided by the embodiment of the application acquire the material surface temperature of the radiation refrigeration material to be measured by measuring the ambient temperature; respectively calculating first proportional values of the atmosphere in all wave bands according to the ambient temperature, and respectively calculating second proportional values of the radiation refrigeration material in all wave bands according to the surface temperature of the material; respectively calculating first weighted emissivity of the atmosphere in each wave band according to the spectral emissivity of the atmosphere in each wave band, and respectively calculating second weighted emissivity of the radiation refrigeration material in each wave band according to the spectral emissivity of the radiation refrigeration material in each wave band; respectively calculating the absorption energy of the radiation refrigeration material in each wave band according to the first proportion value, the first weighted emissivity, the second weighted emissivity and the ambient temperature, and respectively calculating the radiation energy of the radiation refrigeration material in each wave band according to the second proportion value, the second weighted emissivity and the material surface temperature; and determining the heat exchange energy of the radiation refrigeration material according to the absorption energy and the radiation energy, solving the problems that the process of determining the quality of the radiation cooling effect needs to spend a large amount of time and is inaccurate, and realizing the rapid and accurate measurement of the heat exchange energy of the radiation refrigeration material.
The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below to provide a more thorough understanding of the application.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:
fig. 1 is a block diagram of a hardware configuration of a terminal of a method for measuring heat exchange energy of a radiant refrigerant material according to an embodiment of the present application;
FIG. 2 is a flow chart of a method of measuring heat exchange energy of a radiant refrigerant material according to an embodiment of the present application;
FIG. 3 is a first flow chart of a method of measuring heat exchange energy of a radiant refrigerant material according to a preferred embodiment of the present application;
FIG. 4 is a second flow chart of a method of measuring heat exchange energy of a radiant refrigerant material according to the preferred embodiment of the present application;
FIG. 5 is a flow chart III of a method of measuring heat exchange energy of a radiant refrigerant material according to the preferred embodiment of the present application;
FIG. 6 is a schematic illustration of the division into three bands according to infrared wavelengths in accordance with a preferred embodiment of the present application;
FIG. 7 is a graphical representation of the relationship of wavelength bands to atmospheric transmission rate in accordance with a preferred embodiment of the present application;
FIG. 8 is a schematic illustration of the radiative heat exchange between the surface of a material and the outside atmosphere, according to a preferred embodiment of the present application;
FIG. 9 is a schematic illustration of the heat exchange of the surface of the material with the outside atmosphere and solar radiation according to a preferred embodiment of the present application;
FIG. 10 is a timing diagram of the net radiant cooling power of a certain material according to a preferred embodiment of the present application;
FIG. 11 is a timing diagram for determining a surface temperature of a material in accordance with a preferred embodiment of the present application;
FIG. 12 is a graph showing the radiation energy ratio of a material in various wavelength bands as a function of the surface temperature of the material according to a preferred embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided in the present application without any inventive step are within the scope of protection of the present application. Moreover, it should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another.
Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of ordinary skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments without conflict.
Unless defined otherwise, technical or scientific terms referred to herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which this application belongs. Reference to "a," "an," "the," and similar words throughout this application are not to be construed as limiting in number, and may refer to the singular or the plural. The present application is directed to the use of the terms "including," "comprising," "having," and any variations thereof, which are intended to cover non-exclusive inclusions; for example, a process, method, system, article, or apparatus that comprises a list of steps or modules (elements) is not limited to the listed steps or elements, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Reference to "connected," "coupled," and the like in this application is not intended to be limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Reference herein to "a plurality" means greater than or equal to two. "and/or" describes an association relationship of associated objects, meaning that three relationships may exist, for example, "A and/or B" may mean: a exists alone, A and B exist simultaneously, and B exists alone. Reference herein to the terms "first," "second," "third," and the like, are merely to distinguish similar objects and do not denote a particular ordering for the objects.
The various techniques described in this application may be used in applications of radiation refrigeration materials, including temperature calculation of outdoor enclosures and evaluations directly or indirectly related to the temperature, such as building energy consumption evaluation, safety evaluation (high temperatures cause some safety problems), service life evaluation (high temperatures cause some materials or devices to have reduced life), buildings, power cabinets, grain depots, oil storage tanks, and so on.
Before describing and explaining embodiments of the present application, a description will be given of the related art used in the present application as follows:
black body: under any condition, an object that is completely absorbing for any wavelength of extraneous radiation without any reflection, i.e., an object with an absorption ratio of 1.
Black body radiation: any object has the properties of continuously radiating, absorbing and reflecting electromagnetic waves. The radiated electromagnetic wave is different in each wavelength band, that is, has a certain spectral distribution. This spectral distribution is related to the properties of the object itself and its temperature and is therefore called thermal radiation. In order to study the heat radiation law independent of the specific physical properties of substances, physicists defined an ideal object, a black body, as a standard object for heat radiation study.
Equivalent temperature: the equivalent temperature is also called equivalent temperature, and the equivalent temperature rise of solar radiant heat, the solar radiant heat absorbed by the surface of the building is converted into a temperature by an artificial equivalent method, and the value of the temperature is equal to the quotient of the surface heat exchange coefficient of the solar radiant heat absorbed by the outer surface of the enclosure structure in unit area.
ASHRAE Handbook Fundamental 2017: a manual of the american society of heating, ventilating and air conditioning engineers.
The method provided by the embodiment can be executed in a terminal, a computer or a similar operation device. Taking the operation on a terminal as an example, fig. 1 is a hardware structure block diagram of the terminal of the method for measuring the heat exchange energy of the radiation refrigeration material according to the embodiment of the present invention. As shown in fig. 1, the terminal may include one or more (only one shown in fig. 1) processors 102 (the processor 102 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, and optionally, a transmission device 106 for communication functions and an input-output device 108. It will be understood by those skilled in the art that the structure shown in fig. 1 is only an illustration and is not intended to limit the structure of the terminal. For example, the terminal may also include more or fewer components than shown in FIG. 1, or have a different configuration than shown in FIG. 1.
The memory 104 can be used for storing computer programs, for example, software programs and modules of application software, such as a computer program corresponding to the method for measuring heat exchange energy of the radiant refrigerant material in the embodiment of the present invention, and the processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, so as to implement the method described above. The memory 104 may include high speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include memory located remotely from the processor 102, which may be connected to the terminal over a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.
The transmission device 106 is used to receive or transmit data via a network. Specific examples of the network described above may include a wireless network provided by a communication provider of the terminal. In one example, the transmission device 106 includes a Network adapter (NIC) that can be connected to other Network devices through a base station to communicate with the internet. In one example, the transmission device 106 may be a Radio Frequency (RF) module, which is used to communicate with the internet in a wireless manner.
The present embodiment provides a method for measuring heat exchange energy of a radiation refrigeration material, and fig. 2 is a flowchart of a method for measuring heat exchange energy of a radiation refrigeration material according to an embodiment of the present application, and as shown in fig. 2, the flowchart includes the following steps:
step S201, measuring the environment temperature, and obtaining the material surface temperature of the radiation refrigeration material to be measured.
Step S202, according to the environment temperature, respectively calculating a first proportion value of the radiation energy of the atmosphere, which is radiated outwards by the infrared rays of the first wave band, the second wave band and the third wave band, in the total radiation energy of the atmosphere, and according to the surface temperature of the material, respectively calculating a second proportion value of the radiation energy of the radiation refrigeration material, which is radiated outwards by the infrared rays of the first wave band, the second wave band and the third wave band, in the total radiation energy of the radiation refrigeration material, wherein the wave bands of the infrared rays are divided into the first wave band, the second wave band and the third wave band from small to large, and the second wave band is the wave band where the infrared radiation atmosphere window is located.
Step S203, respectively calculating first weighted emissivity of the atmosphere to infrared rays of a first waveband, a second waveband and a third waveband according to the spectral emissivity of the atmosphere under each waveband, and respectively calculating second weighted emissivity of the radiation refrigeration material to infrared rays of the first waveband, the second waveband and the third waveband according to the spectral emissivity of the radiation refrigeration material under each waveband.
Step S204, respectively calculating the absorption energy of the radiation refrigeration material from the atmosphere through infrared rays of the first wave band, the second wave band and the third wave band according to the first proportion value, the first weighted emissivity, the second weighted emissivity and the ambient temperature, and respectively calculating the radiation energy of the radiation refrigeration material radiated to the atmosphere through the infrared rays of the first wave band, the second wave band and the third wave band according to the second proportion value, the second weighted emissivity and the surface temperature of the material.
Step S205, determining the heat exchange energy of the radiation refrigeration material according to the absorption energy and the radiation energy.
Through the steps S201 to S205, the material surface temperature of the radiation refrigeration material to be measured is obtained by measuring the ambient temperature; respectively calculating a first proportional value of the atmosphere in each wave band according to the ambient temperature, and respectively calculating a second proportional value of the radiation refrigeration material in each wave band according to the surface temperature of the material; respectively calculating first weighted emissivity of the atmosphere in each wave band according to the spectral emissivity of the atmosphere in each wave band, and respectively calculating second weighted emissivity of the radiation refrigeration material in each wave band according to the spectral emissivity of the radiation refrigeration material in each wave band; respectively calculating the absorption energy of the radiation refrigeration material in each wave band according to the first proportional value, the first weighted emissivity, the second weighted emissivity and the ambient temperature, and respectively calculating the radiation energy of the radiation refrigeration material in each wave band according to the second proportional value, the second weighted emissivity and the material surface temperature; the heat exchange energy of the radiation refrigeration material is determined according to the absorption energy and the radiation energy, the problems that a large amount of time is needed and the process of determining the quality of the radiation cooling effect is inaccurate are solved, and the heat exchange energy of the radiation refrigeration material is rapidly and accurately measured.
In this embodiment, calculating the first ratio of the radiation energy of the atmosphere radiated outward by the infrared rays of the first, second, and third wavelength bands to the total radiation energy of the atmosphere according to the ambient temperature includes the following steps:
step 1, respectively calculating the radiation energy of the atmosphere radiated outwards by the infrared rays of the first waveband, the second waveband and the third waveband according to the relationship among the ambient temperature, the wavelength in the infrared waveband and the radiation force of the atmosphere and the wavelength, and calculating the total radiation energy of the atmosphere according to the relationship among the ambient temperature, the ambient temperature and the radiation force of the atmosphere.
And 2, obtaining a first proportion value of the radiation energy of the atmosphere radiated outwards by the infrared rays of the first, second and third bands to the total radiation energy of the atmosphere according to the radiation energy of the atmosphere radiated outwards by the infrared rays of the first, second and third bands and the total radiation energy of the atmosphere.
Respectively calculating the radiation energy of the atmosphere in each wave band and the total radiation energy of the atmosphere according to the environment temperature in the step; according to the radiation energy of the atmosphere in each wave band and the total radiation energy of the atmosphere, the first proportion value of the radiation energy of the atmosphere in each wave band to the total radiation energy of the atmosphere is obtained, calculation of the first proportion value of the radiation energy of the atmosphere in each wave band to the total radiation energy of the atmosphere is achieved, and preparation is made for determining the absorption energy of the radiation refrigerating material from the atmosphere subsequently.
In this embodiment, calculating the second ratio of the radiation energy of the radiation refrigeration material radiated outward by the infrared rays of the first wavelength band, the second wavelength band and the third wavelength band to the total radiation energy of the radiation refrigeration material according to the surface temperature of the material includes:
step 1, according to the relationship between the surface temperature of the material, the wavelength in the infrared band and the radiation force of the material and the wavelength, the radiation energy of the radiation refrigeration material radiated outwards by the infrared rays of the first band, the second band and the third band is respectively calculated, and according to the relationship between the surface temperature of the material and the radiation force of the material, the total radiation energy of the radiation refrigeration material is calculated.
And 2, according to the radiation energy of the radiation refrigeration material radiated outwards by the infrared rays of the first wave band, the second wave band and the third wave band and the total radiation energy of the radiation refrigeration material, obtaining a second proportion value of the radiation energy of the radiation refrigeration material radiated outwards by the infrared rays of the first wave band, the second wave band and the third wave band to the total radiation energy of the radiation refrigeration material.
Respectively calculating the radiation energy of the radiation refrigeration material in each wave band and the total radiation energy of the radiation refrigeration material according to the surface temperature of the material in the step; and according to the radiation energy of the radiation refrigeration material in each wave band and the total radiation energy of the radiation refrigeration material, obtaining a second proportion value of the radiation energy of the radiation refrigeration material in each wave band to the total radiation energy of the radiation refrigeration material, realizing the calculation of the second proportion value of the radiation energy of the radiation refrigeration material in each wave band to the total radiation energy of the radiation refrigeration material, and preparing for the subsequent determination of the radiation energy radiated to the atmosphere by the radiation refrigeration material.
In this embodiment, calculating the first weighted emissivity of the atmosphere to the infrared rays of the first, second and third wavelength bands respectively according to the spectral emissivity of the atmosphere at each wavelength band includes:
according to the ambient temperature, the spectral emissivity of the atmosphere under each waveband, the wavelength in the infrared waveband and the relationship between the radiation power of the atmosphere and the wavelength, the first weighted emissivity of the atmosphere to the infrared rays of the first waveband, the second waveband and the third waveband is calculated respectively.
Through the mode, the first weighted emissivity of the atmosphere in each wave band is determined according to the ambient temperature, the calculation of the first weighted emissivity is realized, and preparation is made for the subsequent determination of the absorption energy of the radiation refrigeration material from the atmosphere.
In this embodiment, calculating the second weighted emissivity of the radiation refrigeration material to the infrared rays of the first wavelength band, the second wavelength band and the third wavelength band according to the spectral emissivity of the radiation refrigeration material at each wavelength band includes:
and respectively calculating second weighted emissivity of the radiation refrigeration material to infrared rays of the first waveband, the second waveband and the third waveband according to the relationship among the surface temperature of the material, the spectral emissivity of the radiation refrigeration material under each waveband, the wavelength in the infrared waveband and the radiation force of the atmosphere and the wavelength.
Through the method, the second weighted emissivity of the atmosphere in each wave band is determined according to the surface temperature of the material, so that the calculation of the second weighted emissivity is realized, and preparation is made for the subsequent determination of the radiation energy radiated to the atmosphere by the radiation refrigeration material and the absorption energy absorbed from the atmosphere.
In this embodiment, determining the heat exchange energy of the radiant refrigerant material based on the absorbed energy and the radiant energy comprises:
step 1, determining the total absorption energy absorbed from the atmosphere according to the absorption energy absorbed from the atmosphere by the infrared rays of the first wave band, the second wave band and the third wave band, and determining the total radiation energy radiated to the atmosphere by the radiation refrigeration material according to the radiation energy radiated to the atmosphere by the radiation refrigeration material through the infrared rays of the first wave band, the second wave band and the third wave band.
And 2, determining the heat exchange energy of the radiation refrigerating material according to the total absorption energy and the total radiation energy.
Determining the total absorption energy and the total radiation energy through the absorption energy absorbed from the atmosphere and the radiation energy radiated to the atmosphere in each wave band in the steps; the heat exchange energy of the material is determined according to the total absorption energy and the total radiation energy, so that the heat exchange energy of the radiation refrigeration material can be determined quickly and accurately.
In some of these embodiments, the method of measuring the heat transfer energy of a radiant refrigerant material further comprises the steps of:
step 1, measuring the solar absorptivity, solar radiation intensity and convective heat transfer coefficient of the material.
And 2, calculating solar radiation energy absorbed by the radiation refrigeration material according to the solar absorptivity and solar irradiation, and calculating energy transmitted to the radiation refrigeration material from the outside through thermal convection according to the surface temperature of the material, the ambient temperature and the convection heat transfer coefficient.
And 3, determining the net radiation refrigeration power of the radiation refrigeration material according to the total absorption energy, the total radiation energy, the solar radiation energy absorbed by the material and the energy transmitted outwards by the material through thermal convection.
Calculating the energy transmitted to the radiation refrigeration material through the outside of the thermal convection according to the solar absorptivity, the solar irradiation intensity and the convection heat transfer coefficient in the steps; the net radiation refrigeration power of the radiation refrigeration material is determined according to the total absorption energy, the total radiation energy, the solar radiation energy absorbed by the material and the energy transmitted outwards by the material through heat convection, so that the determination of the net radiation refrigeration power of the radiation refrigeration material is realized, and the cooling effect of the radiation refrigeration material can be determined under the condition of inconsistent solar absorption rate through the net radiation refrigeration power.
In some embodiments, obtaining the material surface temperature of the radiation refrigerating material to be measured comprises the following steps:
step 1, measuring the heat conductivity coefficient, the material thickness, the material lower layer temperature, the solar absorptivity and the solar irradiation intensity of the radiation refrigeration material, and obtaining a third proportional value of the convection heat transfer coefficient and the material surface temperature.
And 2, when the energy balance of the outer surface of the radiation refrigeration material is achieved, calculating the material surface temperature of the radiation refrigeration material according to the heat conductivity coefficient, the material thickness, the material lower layer temperature, the solar absorptivity, the solar radiation, the convective heat transfer coefficient, the ambient temperature, the first weighted emissivity, the second weighted emissivity, the first proportional value and the third proportional value of the radiation refrigeration material.
The material surface temperature of the radiation refrigeration material is calculated through the heat conductivity coefficient, the material thickness, the material lower layer temperature, the solar absorptivity, the solar radiation, the convective heat transfer coefficient, the environment temperature, the first weighted emissivity, the second weighted emissivity, the first proportion value and the third proportion value of the radiation refrigeration material in the steps, and the material surface temperature is obtained through calculation under the condition that the surface temperature of the radiation refrigeration material is unknown.
In some of these embodiments, obtaining the third ratio value includes:
step 1, respectively calculating a third proportion value of radiation energy of the radiation refrigeration material, which is radiated outwards by infrared rays of a first wave band, a second wave band and a third wave band in a common temperature range of the earth surface, in the total radiation energy of the radiation refrigeration material, and determining a relation between the third proportion value and the surface temperature of the material, wherein the common temperature range comprises 250-320K.
And 2, acquiring a first preset value, and obtaining a third proportional value under the surface temperature of the material according to the first preset value and the relation between the third proportional value and the surface temperature of the material.
Obtaining the relation between a third proportional value and the surface temperature of the material through the radiation energy of the radiation refrigeration material in each wave band and the total radiation energy of the material in the step; and determining the third proportion value under the surface temperature of the material according to the first preset value and the relation between the third proportion value and the surface temperature of the material, so that the determination of the third proportion value under the surface temperature of the material is realized, and preconditions are provided for determining the surface temperature of the material under the condition that the surface temperature of the material is unknown.
In some of these embodiments, obtaining the convective heat transfer coefficient comprises: and measuring the wind speed in the environment, and calculating the convective heat transfer coefficient according to the relation between the wind speed and the convective heat transfer coefficient.
Through the mode, the convection heat transfer coefficient is determined according to the relation between the wind speed and the convection heat transfer coefficient, the determination of the convection heat transfer coefficient is realized, and preconditions are provided for determining the surface temperature of the material in the follow-up process under the condition that the surface temperature of the material is unknown.
In some embodiments, the infrared band is divided into three or more bands from small to large, one of the bands is a band in which the infrared radiation atmospheric window is located, and each band is divided according to the difference of emissivity in each band, wherein the band in which the infrared radiation atmospheric window is located is divided into 1 and more than 1 bands according to emissivity, the band smaller than the atmospheric window is divided into 1 and more than 1 bands according to emissivity, and the band larger than the atmospheric window is divided into 1 and more than 1 bands according to emissivity.
By the mode, the wave bands are divided according to the emissivity, and the weighting emissivity of the material in each wave band is calculated more accurately.
The embodiments of the present application are described and illustrated below by means of preferred embodiments.
Fig. 3 is a first flowchart of a method for measuring heat exchange energy of a radiation refrigeration material according to a preferred embodiment of the present application, and as shown in fig. 3, the method for measuring heat exchange energy of a radiation refrigeration material includes the following steps:
step S301, measuring meteorological parameters and obtaining the surface temperature of the material.
Measuring meteorological parameters including ambient temperature
And humidity
Obtaining the surface temperature of the material
Wherein obtaining the material surface temperature comprises obtaining by measurement and obtaining by calculation.
And step S302, measuring and calculating the water column content of the atmosphere.
Passing humidity
And ambient temperature
Measuring and calculating the water column content of the atmosphere
。
Step S303, calculating radiation energy ratio coefficients in three bands at the ambient temperature.
The infrared wavelength is divided into three bands, fig. 6 is a schematic diagram of the infrared wavelength division according to the preferred embodiment of the present application, as shown in fig. 6, the infrared band is divided into three bands from small to large, including A, B and C, the band a is in the range of 0.3 to 8um, the band B is in the range of 8 to 13um, and the band C is in the range of 13 to 25 um, where B is the band where the infrared radiation atmospheric window is located, and the ratio coefficients of the radiation energy of the atmosphere through A, B, C three bands to the total energy of the atmosphere are calculated by the following formula.
Wherein the content of the first and second substances,
is the temperature of the environment and the temperature of the environment,
is that
The ratio coefficient of the radiation energy in the wave band to the total energy of the atmosphere,
a, B or C;
and
respectively representing the lowest value and the highest value of the corresponding wave band;
is the total radiation force of the atmosphere at the ambient temperature according to Stefan-Boltzmann's law,
is a black body radiation constant having a value of 5.67X 10-8W/（m2•k4），
The spectral radiance of a black body, given by:
wherein the content of the first and second substances,
is the size of the wavelength of the light,
is a first radiation constant of 3.7419 × 10-16W•m2；
Is the second radiation constant of 1.4388 × 10-2m•k。
Through the mode, the ratio coefficient of the radiation energy of the atmosphere radiated outwards through infrared rays in three bands of A, B, C to the total energy of the atmosphere is calculated respectively, and preparation is made for the subsequent calculation that the radiation refrigeration material absorbs the radiation energy from the atmosphere through infrared rays in three bands of A, B, C.
Step S304, calculating the weighted emissivity of the atmosphere in three wave bands.
Due to the water column content of
The spectral emissivity of the lower atmosphere is related to the band characteristics of the atmospheric window, fig. 7 is a graph showing the relationship between the band and the atmospheric transmittance according to the preferred embodiment of the present application, and is divided into three bands including A, B and C according to the wavelength of infrared rays, where B is the band in which the atmospheric window of infrared radiation is located, and as can be seen from fig. 7, the atmospheric transmittance is the highest and almost completely transmitted in the atmospheric window band B, and the spectral emissivity of the atmospheric air is obtained by the following formula.
Wherein the content of the first and second substances,
is the spectral emissivity of the atmosphere and,
is the atmospheric transmittance, as can be seen from the above formula and fig. 7, the emissivity of the atmosphere in the atmospheric window band is the lowest and is greatly different from the emissivity in the A, C two bands, so the weighted emissivity of the atmosphere in the A, B, C three bands is calculated by the following formula in consideration of the band characteristic of the atmospheric window in the scheme:
wherein the content of the first and second substances,
is the temperature of the environment and the temperature of the environment,
is the size of the wavelength of the light,
according to the formula (2), the compound is obtained,
is at a water column content of
The spectral emissivity of the lower atmosphere,
a, B or C.
In this way, the weighted emissivity of the atmosphere in the A, B, C bands can be obtained, and preparation is made for the subsequent calculation that the radiation refrigeration material absorbs radiation energy from the atmosphere through infrared rays in A, B, C bands.
Step S305, calculating the radiation energy ratio coefficients in three wave bands at the temperature of the material.
Dividing the infrared ray into three wave bands including A, B and C according to the wavelength of the infrared ray, wherein B is the wave band of the infrared radiation atmospheric window, and calculating the ratio coefficient of the radiation energy of the radiation refrigeration material radiated outwards by the infrared ray of A, B, C three wave bands to the total energy of the radiation refrigeration material by the following formula.
Wherein the content of the first and second substances,
is the temperature of the surface of the material,
a, B, C is the proportion coefficient of radiation energy in three wave bands to total energy of radiation refrigeration material,
is A, B or C, and the content of the C,
is the total radiation force of the radiation refrigeration material at the temperature of the material according to Stefan-Boltzmann law,
is a black body radiation constant having a value of 5.67X 10-8W/（m2•k4），
Is given by the following formula:
wherein the content of the first and second substances,
is the size of the wavelength of the light,
is a first radiation constant of 3.7419 × 10-16W•m2，
Is the second radiation constant of 1.4388 × 10-2m•k。
Through the mode, the proportion coefficient of the radiation energy of the radiation refrigeration material, which is radiated outwards through infrared rays with three wave bands of A, B, C, in the total energy of the radiation refrigeration material is calculated respectively, and preparation is made for the subsequent calculation of the energy of the radiation refrigeration material, which is radiated to the atmosphere through infrared rays with three wave bands of A, B, C.
Step S306, calculating the weighted emissivity of the material in three wave bands.
The spectral emissivity of the material is divided into three bands according to the wavelength of infrared rays, including A, B and C, wherein B is the band in which the infrared radiation atmospheric window is located, and the spectral reflectivity of the material is obtained by the following formula:
wherein the content of the first and second substances,
is the spectral emissivity of the material and is,
is the transmittance of the material, and is,
is the reflectivity of the material, and the weighted emissivity of the radiation refrigeration material in A, B, C three bands is calculated by the following formula:
wherein the content of the first and second substances,
is the temperature of the surface of the material,
is the size of the wavelength of the light,
it is obtained by the following formula (6),
is the spectral emissivity of the radiant cooling material,ia, B or C.
By the method, the weighted emissivity of the radiation refrigeration material in A, B, C three wave bands can be obtained, and preparation is made for subsequent calculation of the radiation refrigeration material absorbing radiation energy from the atmosphere and radiating energy to the atmosphere through infrared rays in A, B, C three wave bands.
Step S307 determines the radiation energy from the atmosphere absorbed by the material.
The absorption of radiant energy from the atmosphere by the radiant refrigerant material in the three bands of A, B, C is obtained by the following calculation.
Wherein the content of the first and second substances,
、
and
are obtained by the following formulas:
wherein the content of the first and second substances,
is the ambient temperature, subscriptiIs A, B or C, and the content of the C,
the compound is obtained by the formula (1),
the compound is obtained by the formula (4),
the formula (8) is used to obtain,
is a black body radiation constant having a value of 5.67X 10-8W/（m2•k4）。
In this manner, it is determined that the radiant refrigerant material absorbs radiant energy from the atmosphere in the A, B, C three bands in preparation for subsequent determination of the heat exchange energy of the radiant refrigerant material surface with the atmosphere.
In step S308, the energy radiated outwards from the surface of the material is determined.
The energy radiated by the radiant cooling material to the atmosphere in the three bands of A, B, C is obtained by the following calculation.
Wherein the content of the first and second substances,
、
and
are obtained by the following formula, respectively.
Wherein the content of the first and second substances,
is the surface temperature, subscript, of the radiation refrigerating materialiIs A, B or C, and the content of the C,
the compound is obtained by the formula (5),
obtained by the formula (8).
Through the mode, the energy radiated to the atmosphere by the radiation refrigerating material in the A, B, C three wave bands is determined, and preparation is made for the subsequent determination of the heat exchange energy between the surface of the radiation refrigerating material and the atmosphere.
Step S309, determining the radiation heat exchange energy of the material surface and the atmosphere.
Fig. 8 is a schematic view of the radiation heat exchange between the surface of the material and the external atmosphere according to the preferred embodiment of the present application, and it can be known from fig. 8 that the radiation heat exchange energy between the surface of the radiation refrigeration material and the atmosphere is obtained by the following formula.
Wherein the content of the first and second substances,
the formula (11) is used to obtain,
obtained by the formula (9).
By the above method, the radiation heat exchange energy between the surface of the radiation refrigeration material and the atmosphere is obtained, the cooling effect of the radiation refrigeration material can be determined under the condition of consistent solar absorption rate, and the higher the radiation heat exchange energy between the surface of the radiation refrigeration material and the atmosphere is, the better the refrigeration effect of the radiation refrigeration material is.
It should be noted that the steps illustrated in the above-described flow diagrams or in the flow diagrams of the figures may be performed in a computer system, such as a set of computer-executable instructions, and that, although a logical order is illustrated in the flow diagrams, in some cases, the steps illustrated or described may be performed in an order different than here. For example, steps S303 to S306 may be interchanged arbitrarily, and the order of calculating the radiant energy ratio in the three bands at the ambient temperature, the emissivity of the atmosphere in the three bands, the radiant energy ratio coefficient in the three bands at the material temperature, and the weighted emissivity of the material in the three bands may be interchanged arbitrarily, and it is determined before step S307.
Fig. 4 is a second flowchart of a method for measuring heat exchange energy of a radiation refrigeration material according to a preferred embodiment of the present application, in which the first flowchart can determine the cooling effect of the radiation refrigeration material under the condition of uniform solar absorptance, and fig. 10 is a timing chart of net radiation cooling power of a determination material according to a preferred embodiment of the present application, in which the second flowchart can determine the cooling effect of the radiation refrigeration material under the condition of non-uniform solar absorptance, as shown in fig. 4, the method for measuring heat exchange energy of a radiation refrigeration material includes the following steps:
step S401, determining that the material absorbs radiation energy from the atmosphere and the energy radiated outwards from the surface of the material.
The radiated energy from the atmosphere absorbed by the material is determined, via step S307, and the energy radiated outward from the surface of the material is determined, via step S308.
Step S402, calculating the solar radiation energy absorbed by the surface of the material.
Measuring solar absorptance of materials
And intensity of solar radiationI The solar radiation energy absorbed by the surface of the material is calculated by:
by the method, the solar radiation energy absorbed by the surface of the material is determined, and preparation is made for the subsequent determination of the net radiation power of the surface of the material.
In step S403, the energy transferred to the material by the outside through thermal convection is calculated.
Measuring the surface temperature of a material
、Ambient temperature
And wind speed, calculating the convective heat transfer coefficient according to the following formula
Wherein
Is the wind speed, and the wind speed,
and
is constant, when the material is exposed outdoors,
the content of the organic acid is 8.3,
is 2.5.
The energy transferred to the material from the outside by thermal convection is calculated by:
by the above method, the energy transferred to the material by the outside of the thermal convection is determined, in preparation for the subsequent determination of the net radiant power of the material surface.
In step S404, the net radiant cooling power of the material is determined.
The net radiant refrigeration power of the material was calculated by:
wherein the content of the first and second substances,
by the acquisition in the step S308, it is possible to,
by the acquisition in the step S307,
by the acquisition in the step S402, the data is,
through step S403.
Through the mode, the net radiation refrigeration power of the material is determined, the quality of the refrigeration effect of the radiation refrigeration material can be judged through the net radiation refrigeration power of the material, and when the net radiation refrigeration power of the material is higher, the refrigeration effect of the material is better.
It should be noted that the steps illustrated in the above-described flow diagrams or in the flow diagrams of the figures may be performed in a computer system, such as a set of computer-executable instructions, and that, although a logical order is illustrated in the flow diagrams, in some cases, the steps illustrated or described may be performed in an order different than here. For example, step S401, step S402, and step S403 may be interchanged arbitrarily, and the energy transmitted to the material by the external environment through thermal convection may be calculated first, and then the solar radiation energy absorbed by the surface of the material may be calculated.
Fig. 5 is a flow chart of a third method for measuring heat exchange energy of a radiation refrigeration material according to a preferred embodiment of the present application, by which the heat exchange energy of the radiation refrigeration material can be determined under the condition of obtaining the surface temperature of the material, and fig. 11 is a timing chart of determining the surface temperature of the material according to the preferred embodiment of the present application, by which the surface temperature of the material can be obtained by calculation, as shown in fig. 5, the method for measuring heat exchange energy of a radiation refrigeration material includes the following steps:
step S501, determining that the material absorbs radiation energy from the atmosphere, energy radiated outward from the surface of the material, solar radiation energy absorbed by the surface of the material, and energy transferred to the material from the outside by thermal convection.
The radiant energy from the atmosphere absorbed by the material is determined by step S307, the energy radiated outward from the surface of the material is determined by step S308, the solar radiant energy absorbed by the surface of the material is determined by step S402, and the energy transferred to the material by the outside of the thermal convection is determined by step S403.
Step S502, energy transferred to the material surface through the outside of the heat conduction is calculated.
Measurement of thermal conductivity of materials
Thickness of material
And the temperature of the lower layer of the outer surface of the material
The energy transferred from the outside to the surface of the material by thermal conduction is calculated by the following formula:
wherein the content of the first and second substances,
is of radiation systemCold material surface temperature.
Through the mode, the energy transmitted to the surface of the material through the outside of the heat conduction is calculated, and preparation is made for the subsequent calculation of the surface temperature of the material.
Step S503, determining the relation between the ratio of the radiation energy radiated outwards by the radiation refrigeration material in each wave band to the total radiation energy of the radiation refrigeration material and the surface temperature of the material.
In a common temperature range of 250-320K on the earth surface, respectively calculating a ratio of radiation energy of the radiation refrigeration material radiated outward by infrared rays of A, B, C three bands to total radiation energy of the radiation refrigeration material, and recording the ratio as a radiation energy ratio of the material in each band, where fig. 12 is a schematic diagram of a relationship between the radiation energy ratio of the material in each band and a surface temperature of the material according to a preferred embodiment of the present application, and as can be seen from fig. 12, the radiation energy ratio of the material in each band is linearly related to the surface temperature of the material, and is represented by the following formula:
wherein the content of the first and second substances,
、
and
is a constant number of times that the number of the first,
is the radiant cooling material surface temperature.
Step S504, calculating the temperature of the outer surface of the material.
Under specific external conditions, the temperature of the surface of the material under the condition of achieving energy balance (namely, steady state of energy conservation) is the equilibrium temperature of the outer surface of the material, namely the temperature of the outer surface of the materialT s 。
Fig. 9 is a schematic view of the heat exchange between the surface of the material and the outside atmosphere and solar radiation, as shown in fig. 9,
is the energy radiated outward from the surface of the material,
by the acquisition in the step S308, it is possible to,
is the radiant energy from the atmosphere that the material absorbs,
by the acquisition in the step S307,
is the solar radiation energy absorbed by the surface of the material,
by the acquisition in the step S402, the data is,
the energy transferred to the material by the thermal convection external environment and the energy transferred to the material surface by the thermal conduction external environment are respectively obtained by the steps S403 and S502, and when the material surface reaches the energy balance, the energy radiated outward from the material surface minus the energy of the material absorbed by the radiation energy from the atmosphere, the energy of the solar radiation absorbed by the material surface, the energy transferred to the material by the thermal convection external environment and the energy transferred to the material surface by the thermal conduction external environment are equal to 0, that is, the following formula is established:
wherein the content of the first and second substances,
is the temperature of the outer surface of the material to be solved,
is the temperature of the environment and the temperature of the environment,
a, B, C, the ratio of the radiation energy in the three wave bands to the total energy of the atmosphere is determined by step S303
，
Is the weighted emissivity of the atmosphere in the three bands of A, B, C, and is determined by step S304
，
A, B, C, the percentage coefficient of radiation energy in three wave bands to total energy of the radiation refrigeration material is determined by the calculation of the formula (19),
is the weighted emissivity of the radiant cooling material in A, B, C three bands, determined by the calculation of equation (8),
is the absorption rate of the solar radiation,
is the intensity of the solar radiation,
and
as determined by the step S402, it is,
is the heat convection coefficient of the heat transfer,
as determined by the step S403, it is,
、
and
respectively the material thermal conductivity, the material thickness and the lower layer temperature of the outer surface of the material are preset
An estimated value is
An estimated value
Obtained by the following formula:
will be represented by the formula (21)
Substituting equations (19) and (8) to obtain estimated values respectively
And
respectively estimate the values
And
substituted by formula (20) to obtain a compound containing
Solving the fourth order equation of unknown solution by using a Fisher-Tropsch method to obtain the temperature of the outer surface of the material
Formula (21) is obtained by the following procedure.
The heat obtained per unit area of the outer surface of the material is shown in the following equation, depending on the thermal equilibrium of the outer surface.
The formula (23) is obtained by derivation.
Wherein the content of the first and second substances,
is the heat convection coefficient of the heat transfer,
is the temperature of the environment and the temperature of the environment,
the temperature of the outer surface of the building envelope,
is the absorption rate of the solar radiation,
is the intensity of the solar radiation,
the long wave radiation heat exchange quantity between the outer surface of the enclosure structure and the environment,
for the comprehensive temperature of outdoor environment, i.e. equivalent to the original ambient temperature
The equivalent temperature value of the solar radiation, the long-wave radiation between the outer surface and the sky and surrounding objects is increased and is an equivalent outdoor temperature, namely
As shown in equation (24).
Taking the horizontal plane according to the empirical value of ASHRAE Handbook Fundamental 2017
3.5-4, and in general, the heat resistance of convection heat transfer on the outer surface of the material is much smaller than the heat resistance in the material, so that the difference between the equivalent outdoor temperature and the surface temperature of the material is small, and therefore, the formula (21) can be used as the estimated value of the temperature of the outer surface of the material.
Through the steps, the temperature of the outer surface of the material can be calculated, on one hand, preparation can be made for subsequently determining the heat exchange energy and the net radiation refrigeration power of the radiation refrigeration material, on the other hand, the quality of the refrigeration effect of the radiation refrigeration material can be judged through the outer temperature of the material, and when the surface energy of the radiation refrigeration material is conserved, the lower the temperature of the outer surface of the material is, the better the refrigeration effect of the radiation refrigeration material is.
It should be noted that the steps illustrated in the above-described flow diagrams or in the flow diagrams of the figures may be performed in a computer system, such as a set of computer-executable instructions, and that, although a logical order is illustrated in the flow diagrams, in some cases, the steps illustrated or described may be performed in an order different than here. For example, step S502 and step S503 may be interchanged, and the relationship between the ratio of the radiation energy radiated outwards by the radiation refrigeration material in each wavelength band to the total radiation energy of the radiation refrigeration material and the surface temperature of the material may be determined, and then the energy transferred to the surface of the material through the heat conduction environment may be calculated.
The above modules may be functional modules or program modules, and may be implemented by software or hardware. For a module implemented by hardware, the modules may be located in the same processor; or the modules can be respectively positioned in different processors in any combination.
The present embodiment also provides an electronic device comprising a memory having a computer program stored therein and a processor configured to execute the computer program to perform the steps of any of the above method embodiments.
Optionally, the electronic apparatus may further include a transmission device and an input/output device, wherein the transmission device is connected to the processor, and the input/output device is connected to the processor.
Optionally, in this embodiment, the processor may be configured to execute the following steps by a computer program:
and S1, measuring the ambient temperature, and obtaining the material surface temperature of the radiation refrigeration material to be measured.
And S2, respectively calculating a first ratio of the radiation energy of the atmosphere radiated outwards by the infrared rays of the first waveband, the second waveband and the third waveband to the total radiation energy of the atmosphere according to the ambient temperature, and respectively calculating a second ratio of the radiation energy of the radiation refrigeration material radiated outwards by the infrared rays of the first waveband, the second waveband and the third waveband to the total radiation energy of the radiation refrigeration material according to the surface temperature of the material, wherein the waveband of the infrared rays is divided into the first waveband, the second waveband and the third waveband from small to large, and the second waveband is a waveband where an infrared radiation atmosphere window is located.
S3, respectively calculating first weighted emissivity of the atmosphere to infrared rays of a first waveband, a second waveband and a third waveband according to the spectral emissivity of the atmosphere under each waveband, and respectively calculating second weighted emissivity of the radiation refrigeration material to infrared rays of the first waveband, the second waveband and the third waveband according to the spectral emissivity of the radiation refrigeration material under each waveband.
And S4, respectively calculating the absorption energy of the infrared rays of the radiation refrigeration material from the atmosphere through the first wave band, the second wave band and the third wave band according to the first proportional value, the first weighted emissivity, the second weighted emissivity and the ambient temperature, and respectively calculating the radiation energy of the radiation refrigeration material radiated to the atmosphere through the infrared rays of the first wave band, the second wave band and the third wave band according to the second proportional value, the second weighted emissivity and the surface temperature of the material.
And S5, determining the heat exchange energy of the radiation refrigeration material according to the absorption energy and the radiation energy.
It should be noted that, for specific examples in this embodiment, reference may be made to examples described in the foregoing embodiments and optional implementations, and details of this embodiment are not described herein again.
In addition, in combination with the method for measuring the heat exchange energy of the radiation refrigeration material in the above embodiments, the embodiments of the present application may provide a storage medium to implement. The storage medium having stored thereon a computer program; the computer program, when executed by a processor, implements any of the above embodiments of the method for measuring heat exchange energy of a radiant refrigerant material.
It should be understood by those skilled in the art that various features of the above embodiments can be combined arbitrarily, and for the sake of brevity, all possible combinations of the features in the above embodiments are not described, but should be considered as within the scope of the present disclosure as long as there is no contradiction between the combinations of the features.
The above examples only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (11)
1. A method for measuring heat exchange energy of a radiation refrigeration material, comprising:
measuring the ambient temperature to obtain the material surface temperature of the radiation refrigeration material to be measured;
respectively calculating a first proportion value of radiation energy of the atmosphere, which is radiated outwards by infrared rays of a first waveband, a second waveband and a third waveband, in the total radiation energy of the atmosphere according to the environment temperature, and respectively calculating a second proportion value of radiation energy of the radiation refrigeration material, which is radiated outwards by infrared rays of the first waveband, the second waveband and the third waveband, in the total radiation energy of the radiation refrigeration material according to the surface temperature of the material, wherein the waveband of the infrared rays is divided into the first waveband, the second waveband and the third waveband from small to large, and the second waveband is a waveband in which an infrared radiation atmosphere window is located;
respectively calculating first weighted emissivity of the atmosphere to infrared rays of a first waveband, a second waveband and a third waveband according to the spectral emissivity of the atmosphere under each waveband, and respectively calculating second weighted emissivity of the radiation refrigeration material to infrared rays of the first waveband, the second waveband and the third waveband according to the spectral emissivity of the radiation refrigeration material under each waveband;
calculating the absorption energy of the radiation refrigeration material from the atmosphere through infrared rays of a first wave band, a second wave band and a third wave band according to the first proportion value, the first weighted emissivity, the second weighted emissivity and the ambient temperature, and calculating the radiation energy of the radiation refrigeration material radiated to the atmosphere through infrared rays of the first wave band, the second wave band and the third wave band according to a second proportion value, the second weighted emissivity and the surface temperature of the material;
and determining the heat exchange energy of the radiation refrigeration material according to the absorption energy and the radiation energy.
2. The method of claim 1, wherein calculating a first ratio of radiant energy of the atmosphere radiated outward by the infrared rays of the first, second, and third bands to total radiant energy of the atmosphere based on the ambient temperature comprises:
according to the relationship among the ambient temperature, the wavelength in the infrared band and the radiation force of the atmosphere and the wavelength, the radiation energy of the atmosphere radiated outwards by the infrared rays of the first band, the second band and the third band is calculated respectively, according to the relationship among the ambient temperature, the ambient temperature and the radiation force of the atmosphere, the total radiation energy of the atmosphere is calculated, and according to the radiation energy of the atmosphere radiated outwards by the infrared rays of the first band, the second band and the third band and the total radiation energy of the atmosphere, a first proportion value of the radiation energy of the atmosphere radiated outwards by the infrared rays of the first band, the second band and the third band to the total radiation energy of the atmosphere is obtained.
3. The method for measuring heat exchange energy of a radiant refrigerant material as claimed in claim 1, wherein calculating a second ratio of radiant energy of the radiant refrigerant material radiated outward by infrared rays of a first wavelength band, a second wavelength band and a third wavelength band to total radiant energy of the radiant refrigerant material according to the surface temperature of the material comprises:
according to the relationship among the material surface temperature, the wavelength in the infrared band and the radiation force of the material and the wavelength, the radiation energy of the radiation refrigeration material radiated outwards by infrared rays of a first band, a second band and a third band is calculated respectively, according to the relationship among the material surface temperature, the material surface temperature and the radiation force of the material, the total radiation energy of the radiation refrigeration material is calculated, and according to the radiation energy of the radiation refrigeration material radiated outwards by infrared rays of the first band, the second band and the third band and the total radiation energy of the radiation refrigeration material, a second proportion value of the radiation energy of the radiation refrigeration material radiated outwards by infrared rays of the first band, the second band and the third band to the total radiation energy of the radiation refrigeration material is obtained.
4. The method of claim 1, wherein calculating the first weighted emissivity of the atmosphere to the infrared radiation of the first, second, and third wavelength bands based on the spectral emissivity of the atmosphere at each wavelength band comprises:
and respectively calculating first weighted emissivity of the atmosphere to infrared rays of a first waveband, a second waveband and a third waveband according to the relationship among the ambient temperature, the spectral emissivity of the atmosphere under each waveband, the wavelength in the infrared waveband and the radiation power of the atmosphere and the wavelength.
5. The method of claim 1, wherein calculating the second weighted emissivity of the radiant cooling material for the infrared radiation of the first, second, and third wavelength bands based on the spectral emissivity of the radiant cooling material at each wavelength band comprises:
and respectively calculating second weighted emissivity of the radiation refrigeration material to infrared rays of the first waveband, the second waveband and the third waveband according to the relationship among the surface temperature of the material, the spectral emissivity of the radiation refrigeration material under each waveband, the wavelength in the infrared waveband and the radiation force of the atmosphere and the wavelength.
6. The method of claim 1, wherein determining the heat exchange energy of the radiant refrigerant material from the absorbed energy and the radiant energy comprises:
determining the total absorption energy absorbed from the atmosphere according to the absorption energy absorbed from the atmosphere by the infrared rays of the first wave band, the second wave band and the third wave band, determining the total radiation energy radiated to the atmosphere by the radiation refrigeration material according to the radiation energy radiated to the atmosphere by the infrared rays of the first wave band, the second wave band and the third wave band, and determining the heat exchange energy of the radiation refrigeration material according to the total absorption energy and the total radiation energy.
7. The method of measuring heat exchange energy of a radiant refrigerant material as set forth in claim 1, further comprising:
measuring the solar absorptivity, solar radiation intensity and convective heat transfer coefficient of the material;
calculating solar radiation energy absorbed by the radiation refrigeration material according to the solar absorptivity and the solar radiation, and calculating energy transmitted to the radiation refrigeration material from the outside through thermal convection according to the surface temperature of the material, the ambient temperature and the convection heat transfer coefficient;
and determining the net radiation refrigeration power of the radiation refrigeration material according to the absorbed energy, the radiation energy, the solar radiation energy absorbed by the radiation refrigeration material and the energy transmitted to the radiation refrigeration material through the heat convection outside.
8. The method for measuring the heat exchange energy of the radiation refrigeration material as claimed in claim 1, wherein the step of obtaining the material surface temperature of the radiation refrigeration material to be measured comprises the following steps:
measuring the heat conductivity coefficient, the thickness and the lower layer temperature of the radiation refrigeration material, the solar absorptivity and the solar irradiation intensity of the material, and obtaining a third proportional value of the convective heat transfer coefficient and the surface temperature of the material;
when the energy balance of the outer surface of the radiation refrigeration material is achieved, the material surface temperature of the radiation refrigeration material is calculated according to the heat conduction coefficient of the radiation refrigeration material, the material thickness, the material lower layer temperature, the solar absorptivity of the material, the solar irradiation, the convective heat transfer coefficient, the environment temperature, the first weighted emissivity, the second weighted emissivity, the first proportional value and the third proportional value.
9. A method of measuring heat exchange energy of a radiant refrigerant material as set forth in claim 8, wherein obtaining a third proportional value comprises:
respectively calculating a third proportion value of radiation energy of the radiation refrigeration material, which is radiated outwards by infrared rays of a first wave band, a second wave band and a third wave band, in the common temperature range of the earth surface, in the total radiation energy of the radiation refrigeration material, and determining the relation between the third proportion value and the surface temperature of the material, wherein the common temperature range comprises 250-320K;
and acquiring a first preset value, and acquiring a third proportion value under the surface temperature of the material according to the first preset value and the relation between the third proportion value and the surface temperature of the material.
10. An electronic device comprising a memory and a processor, wherein the memory has stored therein a computer program, and the processor is configured to execute the computer program to perform the method of measuring heat exchange energy of a radiant refrigerant material as claimed in any one of claims 1 to 9.
11. A storage medium, characterized in that a computer program is stored in the storage medium, wherein the computer program is arranged to execute the method of measuring heat exchange energy of a radiation refrigerating material according to any one of claims 1 to 9 when running.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150083195A1 (en) * | 2012-03-22 | 2015-03-26 | Sunpartner | Transparent solar energy collector |
| CN106092628A (en) * | 2016-06-06 | 2016-11-09 | 武汉理工大学 | A kind of civil engineering structure solar radiation temperature-effect analysis method and system |
| US20170211408A1 (en) * | 2016-01-21 | 2017-07-27 | United Technologies Corporation | Heat flux measurement system |
| CN111487283A (en) * | 2020-06-29 | 2020-08-04 | 宁波瑞凌新能源科技有限公司 | Radiation refrigeration power measuring device and system |
-
2020
- 2020-11-24 CN CN202011333570.4A patent/CN112525950A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150083195A1 (en) * | 2012-03-22 | 2015-03-26 | Sunpartner | Transparent solar energy collector |
| US20170211408A1 (en) * | 2016-01-21 | 2017-07-27 | United Technologies Corporation | Heat flux measurement system |
| CN106092628A (en) * | 2016-06-06 | 2016-11-09 | 武汉理工大学 | A kind of civil engineering structure solar radiation temperature-effect analysis method and system |
| CN111487283A (en) * | 2020-06-29 | 2020-08-04 | 宁波瑞凌新能源科技有限公司 | Radiation refrigeration power measuring device and system |
Non-Patent Citations (1)
| Title |
|---|
| 许伟平: ""辐射制冷外围护结构综合节能技术研究"", 《2020国际绿色建筑与建筑节能大会论文集》 * |
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