CN114046296A - Intelligent temperature control system of hydraulic oil tank and design method thereof - Google Patents

Intelligent temperature control system of hydraulic oil tank and design method thereof Download PDF

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CN114046296A
CN114046296A CN202111314559.8A CN202111314559A CN114046296A CN 114046296 A CN114046296 A CN 114046296A CN 202111314559 A CN202111314559 A CN 202111314559A CN 114046296 A CN114046296 A CN 114046296A
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oil tank
temperature
hydraulic oil
heating
heat dissipation
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CN114046296B (en
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何祯鑫
李良
冯永保
于传强
欧阳和
李淑智
韩小霞
魏小玲
王欣
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Rocket Force University of Engineering of PLA
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0423—Cooling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0427—Heating
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
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    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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Abstract

The invention discloses an intelligent temperature control system of a hydraulic oil tank and a design method thereof, wherein the system is arranged in the hydraulic oil tank and comprises a heating device, a heat dissipation device and a temperature measurement feedback device; the heating device comprises an external solid-state relay, a temperature controller and a heating clapboard which are connected with each other, the heating clapboard is encapsulated by an aluminum alloy shell, and a plurality of PTC thermosensitive electrics are arranged in the heating clapboardBlocking; the heat dissipation device is a heat dissipation plate encapsulated in a phase change material interlayer on the side wall of the hydraulic oil tank; the temperature measurement feedback device consists of a plurality of PT100 type thermal resistors; when in use, the ceramic-based PTC thermistor is used for heating hydraulic oil, and Na is used2SO4·10H2The cooling plate made of the O-based crystalline hydrated salt phase-change material can cool hydraulic oil, intelligent heating and cooling of the hydraulic oil tank are achieved, local high temperature in the oil heating process can be effectively prevented, the oil deterioration condition can be effectively prevented, and the oil tank cooling device has the advantages of being remarkable in temperature control function and capable of being suitable for wide temperature range application occasions.

Description

Intelligent temperature control system of hydraulic oil tank and design method thereof
Technical Field
The invention relates to the technical field of hydraulic pressure, in particular to an intelligent temperature control system of a hydraulic oil tank and a design method thereof.
Background
The hydraulic oil tank is a special container used for storing working media required by a hydraulic system and is an important accessory in a crane hydraulic system;
the temperature value of the hydraulic oil has great influence on the working state of a hydraulic system, particularly the working of hydraulic elements, when the oil temperature in an oil tank is too low, the viscosity of the oil becomes high, internal friction is generated, the flow resistance is increased, the self-absorption capacity is reduced, the oil supply of the hydraulic oil is insufficient, an execution mechanism acts slowly, the heating condition is caused, and the working efficiency is low; when the oil temperature in the oil tank is too high, the viscosity is rapidly reduced, and when the temperature of the hydraulic oil reaches 60 ℃, the coking and deterioration speed of the hydraulic oil is greatly accelerated when the temperature rises to 8-10 ℃; the viscosity of the oil is reduced to thin a lubricating oil film, the friction between hydraulic elements is intensified, the leakage is increased due to insufficient sealing performance, the hydraulic system is failed, and the normal operation cannot be realized;
therefore, a control system capable of automatically controlling the oil temperature of the hydraulic oil tank is designed to meet the application requirements of the hydraulic system under complex working conditions of high and low temperature, multiple regions, long time, high strength and the like, and the problem to be solved in the field is needed urgently.
Disclosure of Invention
Aiming at the problems, the invention aims to provide an intelligent temperature control system of a hydraulic oil tank and a design method thereof2SO4·10H2The cooling plate made of the O-based crystalline hydrated salt phase-change material can cool hydraulic oil, intelligent heating and cooling of the hydraulic oil tank can be achieved, local high temperature in the oil heating process can be effectively prevented, the oil deterioration condition can be prevented, and the oil tank cooling device has the advantages of being remarkable in temperature control function and capable of being suitable for wide temperature range application occasions.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
an intelligent temperature control system of a hydraulic oil tank is arranged in the hydraulic oil tank and comprises a heating device, a heat dissipation device and a temperature measurement feedback device;
the heating device comprises a heating partition plate and a heating unit packaged in the heating partition plate, the heating partition plate is sealed by aluminum alloy, and the heating unit is connected with a power supply and a temperature measurement feedback device;
the heat dissipation device is a heat dissipation unit encapsulated in a phase change material interlayer on the inner sides of the heat dissipation plates on the side wall and the bottom wall of the hydraulic oil tank, and the heat dissipation unit is made of Na2SO4·10H2O is prepared from a main body crystalline hydrous salt phase-change material;
the temperature measurement feedback device comprises a PT100 type thermal resistor, a temperature controller, a temperature sensor and a liquid crystal display screen, wherein the PT100 type thermal resistor is installed at different positions and depths in a hydraulic oil tank and is connected with the temperature controller through an on-off control switch, the temperature controller controls the work of a heat dissipation unit through setting a target temperature, and the temperature sensor is connected with the liquid crystal display embedded in the upper cover of the oil tank to display the temperature of oil liquid in real time.
Preferably, the heating unit consists of a plurality of B-100 type ceramic-based PTC thermistors which are connected with each other, the PTC thermistors are connected with a power supply anode and a power supply cathode, and the power supply supplies electric energy to the PTC thermistors; meanwhile, a lead of the PTC thermistor is connected with the solid-state relay and the temperature controller through a copper tube, and the PTC thermistor is controlled to work through the temperature controller.
Preferably, the encapsulation form of the heat dissipation unit in the phase change material interlayer of the side wall of the hydraulic oil tank is phase change microcapsules, the heat dissipation plate is installed in the clamping grooves in the bottom surface and the side surface of the oil tank in a non-spot welding and clamping groove type mode, the heat dissipation unit is subjected to combined encapsulation through the heat dissipation plate, the phase change microcapsules are separately encapsulated in the frame partition plate and the bottom plate of the oil tank, and the side frame partition plate and the bottom plate are mutually isolated.
Preferably, the side frame partition is internally provided with a solid-liquid microcapsule heat dissipation material, and the bottom plate is internally provided with a solid-solid phase change heat dissipation material.
Preferably, the temperature controller is an AI-519 type temperature controller, the precision is 0.3 level, and double output of heating and refrigerating can be realized.
The design method of the intelligent temperature control system of the hydraulic oil tank comprises the following steps
S1, designing an intelligent heating device of a hydraulic oil tank;
s101, establishing resistance value models of the PTC thermistors at different environmental temperatures;
s102, calculating the power of a heating device in the hydraulic oil tank under the condition of not considering the heat dissipation of the oil tank;
s103, determining the size of the heating device according to the obtained power design of the heating device;
s2, designing an intelligent heat dissipation device of the hydraulic oil tank;
s201, calculating the heating value of a hydraulic system in a hydraulic oil tank;
s202, calculating the heat dissipation capacity of a hydraulic system in a hydraulic oil tank;
and S3, arranging a PT100 type thermal resistor in the hydraulic oil tank.
Preferably, the process of establishing the resistance model of the PTC thermistor at different environmental temperatures in step S101 includes
(1) Placing a B-100 type ceramic matrix PTC thermistor in a constant temperature water tank, measuring a corresponding resistance value by adjusting the water temperature, measuring the temperature and the numerical value of the resistance by using a temperature measuring instrument and a resistance measuring instrument, and recording data to obtain a resistance-temperature characteristic curve of the thermistor;
(2) the Curie temperature of the B-100 type ceramic matrix PTC thermistor can be obtained through a resistance-temperature characteristic curve to be 60 ℃, and when the temperature of the PTC thermistor is lower than 60 ℃, the resistivity is about 3900Q cm and is always a fixed value; when the temperature of the PTC thermistor is above 60 ℃, the temperature is increased to 80 ℃, and the resistivity of the PTC thermistor is increased exponentially;
(3) fitting the data of the resistance value and the temperature of the B-100 type ceramic-based PTC thermistor at 60 ℃ on a computer to obtain:
ρ(PTC)＝10β+BT (1)
in the formula (1), β represents a characteristic parameter relating to resistance; b represents the slope of the resistance-temperature curve;
(4) the resistance value can be expressed as:
Figure BDA0003343186400000041
in the formula (2), S represents the cross-sectional area of the PTC thermistor, and D represents the thickness of the PTC thermistor;
the temperature coefficient of the PTC thermistor can be obtained as:
Figure BDA0003343186400000042
in the formula (3), T represents the temperature of the PTC thermistor, and the resistance value of the PTC thermistor at different environmental temperatures can be calculated by the formula (3).
Preferably, the calculation process of the heating device power and the heating device size in the hydraulic oil tank in the step S102 and the step S103 comprises
(1) Calculation of heating device power in hydraulic tank
Setting the power of the heating device as Pj, the effective volume in the hydraulic oil tank as V, and the ambient temperature of the oil tank as t1The preset temperature t for heating the hydraulic oil2The heating time is T, the specific heat capacity of the hydraulic oil is rho, the density of the hydraulic oil is C, and the calculation model for establishing the power required by the heating device is as follows:
Figure BDA0003343186400000051
according to the formula (4), under the condition that the heat dissipation of the oil tank is not considered, the power required by the heating device can be obtained, the power of the heating device is further determined, and a ceramic-based PTC thermistor with the model number of B-100 is used as a heating element;
(2) design of heating device size
Setting the heating energy of the required heating device as Q, the heat transfer coefficient as K, the surface area of the required heating device as A, and the temperature change value of the hydraulic oil as delta t, the obtained surface area of the heating device is as follows:
Q＝KAΔt (5)
from the formula (5), it is possible to obtain
A＝0.12m2 (6)
A plurality of B-100 type ceramic-based PTC thermistors are connected and encapsulated by an aluminum alloy shell to form a heating clapboard which is arranged in a hydraulic oil tank.
Preferably, the step S201 of calculating the heating value of the hydraulic system in the hydraulic oil tank includes
(1) Calculation of heat production of hoisting mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure BDA0003343186400000052
in formula (7), P1It is indicated that the working pressure is,Q1represents the flow rate of the pump, and η represents the total efficiency;
the heat production quantity of the hydraulic valve is as follows: h is12＝P2Q2 (8)
In formula (8), P2Indicating the regulated pressure value, Q, of the relief valve2Indicating flow through the overflow valve box;
the heat production of the pipeline is as follows: h is13P is (0.03-0.05), and (0.03-0.05) is the heating power coefficient of the pipeline;
the total heat production capacity of the hoisting mechanism is as follows:
Figure BDA0003343186400000061
(2) calculation of heat production of slewing mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure BDA0003343186400000062
the heat production quantity of the hydraulic valve is as follows: h is22＝P2Q2 (11)
The heat production of the pipeline is as follows: h is23＝(0.03～0.05)P (12)
The total heat production capacity of the slewing mechanism is as follows:
Figure BDA0003343186400000063
(3) calculation of heat production of luffing mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure BDA0003343186400000064
the heat production quantity of the hydraulic valve is as follows: h is32＝P2Q2 (15)
The heat production of the pipeline is as follows: h is33＝(0.03～0.05)P (16)
Total heat production of the luffing mechanism:
Figure BDA0003343186400000065
according to the calculation result, the total heat production quantity of the hydraulic system is as follows:
W＝W1+W2+W3 (18)。
preferably, the calculation process of the heat dissipation capacity of the hydraulic system in the hydraulic oil tank in step S202 includes
(1) The side lengths of the hydraulic oil tank are respectively set as x, y and z, and according to the designed length-width-height ratio of the hydraulic oil tank, the side length model of the hydraulic oil tank is as follows:
Figure BDA0003343186400000071
when the function is used for solving A maximum, each side length is 1: 2: 3, so that A is 6.66V2/3；
(2) If the heat dissipation coefficient of the material of the heat dissipation device is k, the area available for heat dissipation is a, and the difference between the ambient temperature and the working temperature is Δ T, the total heat dissipation capacity of the hydraulic oil tank system is as follows:
w1＝kA(ΔT)t (20)
(3) calculating the oil heat storage capacity of the hydraulic system:
Δw＝cρV(ΔT) (21)
in the formula (21), c is the specific heat capacity of the hydraulic oil, ρ is the density of the hydraulic oil, and V is the volume capacity of the hydraulic oil tank;
(4) phase change material quality determination
According to the above formulas (18), (20) and (21), the heat production quantity, the heat dissipation quantity and the oil liquid heat storage quantity of the system can be obtained, when the heat absorption quantity is equal to the heat dissipation quantity, the oil liquid temperature reaches a fixed value, the hydraulic system reaches a thermal equilibrium state, and the system heat production quantity, the heat dissipation quantity and the oil liquid heat storage quantity have the following constraint relation:
Ht＝Nt+Lm+ΔW (22)
in formula (22), L is the latent heat of phase change of the phase change material;
selecting a crystalline hydrated salt Na according to the heat balance condition of the formula (22) and the calculation result2SO4·10H2O is the phase change material for heat dissipation, and the required mass is calculated as:
Figure BDA0003343186400000072
because the volume of the phase-change material changes along with the phase-change material in the phase-change process, for the sake of safety, the volume of the phase-change material is obtained by calculating in a liquid state with smaller density:
Figure BDA0003343186400000073
the invention has the beneficial effects that: the invention discloses an intelligent temperature control system of a hydraulic oil tank and a design method thereof, compared with the prior art, the invention has the improvement that:
according to the intelligent temperature control system for the hydraulic oil tank, analysis and design are carried out from the two aspects of heating and heat dissipation of the hydraulic oil tank, the intelligent temperature control system for the hydraulic oil tank is designed, when the intelligent temperature control system is used, the ceramic-based PTC thermistor is used for heating hydraulic oil, the heating time is short, the temperature control precision is high, self-adaptive temperature control can be realized, and the quick starting of hydraulic equipment is met; by using Na2SO4·10H2O is a main body crystalline hydrated salt phase-change material, and the heat dissipation unit is used for dissipating heat of hydraulic oil, so that the working performance of a hydraulic system is prevented from being influenced by overhigh oil temperature; the system has the integrated design of the oil tank with low-temperature heating and high-temperature heat dissipation, has obvious temperature control function, can adapt to wide-temperature-range application occasions, and has the advantages of high temperature control precision, short heating time, obvious temperature control function and adaptability to wide-temperature-range application occasions.
Drawings
Fig. 1 is an installation diagram of the intelligent temperature control system of the hydraulic oil tank.
FIG. 2 is a general scheme diagram of a design method of an intelligent temperature control system of a hydraulic oil tank.
Fig. 3 is a graph of resistance versus temperature characteristics according to the present invention.
FIG. 4 is a design flow chart of the intelligent temperature control system of the hydraulic oil tank.
FIG. 5 is a schematic view of the structure of the heating baffle of the present invention.
FIG. 6 is an AI-516 model artificial intelligence temperature controller of the present invention.
FIG. 7 shows a PT100 type thermal resistor according to the present invention.
Fig. 8 is a control flow chart of the heating apparatus of the present invention.
FIG. 9 is a working schematic diagram of the intelligent temperature control system of the hydraulic oil tank of the present invention.
Fig. 10 is a working flow chart of the intelligent temperature control system of the hydraulic oil tank.
Wherein: 1. the hydraulic oil tank, 2, heating baffle, 3, heating panel.
Detailed Description
In order to make those skilled in the art better understand the technical solution of the present invention, the following further describes the technical solution of the present invention with reference to the drawings and the embodiments.
Example 1: an intelligent temperature control system of a hydraulic oil tank and a design method thereof are shown in figures 1-8.
In order to ensure that the temperature of oil in the oil tank is always in a normal working range, the general scheme of the oil tank is designed, two systems of low-temperature heating and high-temperature heat dissipation are designed, a proper heating material and a proper heat dissipation material are selected, the size and the capacity of the materials are calculated, the heat production quantity and the heat dissipation quantity are calculated under a heat balance condition, and a heat balance model is established, wherein the design idea of the design method of the intelligent temperature control system of the hydraulic oil tank is shown in figure 2;
the overall scheme design of the hydraulic oil tank system comprises the design of a heating device and a heat radiating device of an oil tank, and is mainly considered from the following aspects: the size and the structure of the oil tank are reasonably designed, and the power consumption of the system is reduced; secondly, the heating device has a good heating effect to ensure the normal operation of the system in cold start under a low-temperature environment; the heating device has simple structure and convenient control, so as to meet the requirement of temperature control precision; the phase-change material has good heat-conducting property, fast heat absorption and high heat dissipation efficiency;
the design method of the intelligent temperature control system of the hydraulic oil tank specifically comprises
S1, design and calculation of intelligent heating device of hydraulic oil tank
For intelligent heating materials, currently, heating materials such as heating films, epoxy heating plates, silica gel heating sheets and the like mainly exist, the defects of high manufacturing cost, fast aging, large energy loss and the like exist, and the ceramic-based PTC thermistor can effectively overcome the problems; as a common PTC heating material, compared with a traditional electric heating tube heating control system, the ceramic-based PTC thermistor has the advantages of small thermal resistance, high heat exchange efficiency and the like, the temperature of oil can be stably controlled near the Curie temperature without controlling components, and the capillary tension generated by the ultramicro porous channel in the ceramic matrix can keep heat dissipation more uniform, so that the condition of local high temperature is not easy to occur, the stability of the whole structure of the material can be ensured, and the safety and reliability of the system can be greatly improved; the ceramic-based PTC thermistor is designed into a constant-temperature, power-saving and environment-friendly heating device, an electric heating element is manufactured to replace the conventional common resistor to heat oil, the self-adaptive temperature of the oil tank can be realized, the functions of a heater and a controller are realized, and the ceramic-based PTC thermistor does not generate the surface red phenomenon due to the positive temperature resistance coefficient effect, so that the potential safety hazards of electric leakage, fire and the like can be effectively avoided;
in order to ensure the reliable performance of the ceramic-based PTC thermistor material, firstly, the performance of the thermistor is identified, and whether the Curie temperature is 60 ℃ or not is verified, and the specific experimental steps are as follows:
s101, establishing resistance value models of the PTC thermistors at different environmental temperatures, which comprises
(1) Placing a B-100 type ceramic-based PTC thermistor in a constant temperature water tank, measuring a corresponding resistance value by adjusting the water temperature, measuring the temperature and the resistance value by using a temperature measuring instrument and a resistance measuring instrument, recording data, and collating experimental data to obtain a resistance-temperature characteristic curve, wherein the resistance-temperature characteristic curve is shown in FIG. 3;
(2) as can be seen from FIG. 3, the Curie temperature of the B-100 ceramic-based PTC thermistor obtained from the resistance-temperature characteristic curve is 60 ℃, and when the temperature of the PTC thermistor is lower than 60 ℃, the resistivity is about 3900Q cm, which is always a constant value; when the temperature of the PTC thermistor is above 60 ℃, the temperature is increased to 80 ℃, and the resistivity of the PTC thermistor is increased exponentially;
(3) fitting the data of the resistance value and the temperature of the B-100 type ceramic-based PTC thermistor at 60 ℃ on a computer to obtain:
ρ(PTC)＝10β+BT (1)
in the formula (1), β represents a characteristic parameter relating to resistance; b represents the slope of the resistance-temperature curve;
(4) the resistance value can be expressed as:
Figure BDA0003343186400000111
in the formula (2), S represents the cross-sectional area of the PTC thermistor and has a size of 50mm2D represents the thickness of the PTC thermistor, and the size is 5 mm;
the temperature coefficient of the PTC thermistor can be obtained as:
Figure BDA0003343186400000112
in the formula (3), T represents the temperature of the PTC thermistor, and the resistance value of the PTC thermistor under different environmental temperatures can be calculated through the formula (3);
in order to improve the working efficiency of heating instrument equipment and realize self-adaptive temperature control, a PTC thermistor with proper temperature-resistance characteristics and a physical size thereof are selected, and the temperature control precision is effectively improved by combining the characteristics of a working medium; in order to realize the cold start of the hydraulic system in a low-temperature environment, the coking and deterioration conditions of hydraulic oil are considered in the model selection design process of the heating device, and the size scale of the heating device is calculated and designed;
s102, calculating the power of a heating device in the hydraulic oil tank without considering the heat dissipation of the oil tank, including
The calculation content comprises the required power and the design size of the heating device, and the requirement is determined according to the use technical requirementsThe volume, heating time, temperature range and ambient temperature of the oil to be heated; the invention relates to a hydraulic system, which has the oil tank volume of 200L and the effective volume of 160L, and is used for heating hydraulic oil from the ambient temperature of minus 30 ℃ to the preset temperature of 10 ℃ within 15 minutes according to requirements, maintaining the two temperatures in balance, setting the power of a heating device as Pj, the effective volume in a hydraulic oil tank as V, and the ambient temperature of the oil tank as t1The preset temperature t for heating the hydraulic oil2The heating time is T, the specific heat capacity of the hydraulic oil is rho, the density of the hydraulic oil is C, and the calculation model for establishing the power required by the heating device is as follows:
Figure BDA0003343186400000121
according to the formula (4), under the condition that the heat dissipation of the oil tank is not considered, the required power Pj of the heating device is obtained as 4kW by substituting the formula; determining the power of a heating device, selecting a ceramic-based PTC thermistor with the model of B-100 as a heating element, wherein the power is 500W, and the number of the PTC thermistor is determined to be 8;
s103, determining the size of the heating device according to the obtained power design of the heating device, including
The required heating power calculated by the foregoing was 4kW, the heating element was 8 pieces of 500W ceramic-based PTC thermistor, and the thermal conductivity of aluminum was known to be 237W/m2Temperature rises by 40 ℃ for 15 minutes, according to known conditions, the required heating energy of the heating device is Q, the heat transfer coefficient is K, the required surface area of the heating device is A, the hydraulic oil temperature change value is delta t, and the obtained surface area of the heating device is as follows:
Q＝KAΔt (5)
from the formula (5), it is possible to obtain
A＝0.12m2 (6)
In order to effectively improve the heating power, 8 500W ceramic-based PTC thermistors are packaged into a heating clapboard of 300mm multiplied by 200mm multiplied by 8mm, the packaging material is aluminum alloy, the thermistors in the heating clapboard are provided with a power supply anode and a power supply cathode, the circuit connection among a plurality of thermistors and the power supply anode and the power supply cathode form a complete power-on circuit, and the heating clapboard is shown in figure 5;
s104. design of operation part of heating device
According to the design requirement of a heating system, the temperature control system has the characteristics of high temperature control precision, high automation degree, high heating efficiency and the like, so that the design comprises an electric heating automatic control unit, a temperature monitoring unit, an early warning protection unit and a circulation control unit; the temperature of oil in the oil tank can be measured and displayed in real time, the target temperature is set, the heating device is automatically controlled to work, the oil temperature is accurately adjusted, a power-off signal can be received and sent, and the working current of the heating device is cut off in an emergency;
the installation scheme is as follows: two sets of heating partition plates are arranged in the oil tank and can be synchronously used as oil tank partition plates, so that oil liquid can fully flow in the oil tank, impurity precipitation is promoted, and the phenomenon that the impurities in an oil return area are impacted to an oil absorption area to cause pipeline blockage is prevented; the power supply required by the heating partition plate can be supplied by external power supplies such as commercial power, a proper target temperature is set by a temperature controller through an external solid-state relay, the heating device is controlled to work to heat oil in the oil tank and display the oil in real time, an AI-516 type temperature controller is selected, the precision is 0.3 grade, heating and refrigerating double output can be realized, a satisfactory control effect can be obtained without artificially setting control parameters by self-setting (AT) operation, the temperature control is stable, the use is simple, the temperature control precision can be further improved, and in addition, the temperature controller supports various thermocouples, thermal resistors, linear voltage, current, resistors, radiation (infrared) thermometers and the like, as shown in figure 6; the temperature of the hydraulic oil is measured in real time by 3 PT100 type thermal resistors installed at different positions inside the hydraulic oil tank, as shown in FIG. 7; when the oil temperature is about to reach a preset temperature value, the temperature controller enables the heating device to be powered off and stop heating immediately through the on-off control switch, and the temperature of the hydraulic oil is controlled to accurately reach a set value; when the temperature of the hydraulic oil is affected by the external working environment and is lower than the normal working temperature range of the hydraulic oil, the heating device is awakened by the controller, the heating partition plate heats the hydraulic oil again, the oil temperature rises to reach the normal working range, the whole process can be accurately heated to a preset specific temperature value by controlling the heating device, constant temperature control is realized, and the temperature of the hydraulic oil is always in the normal working range.
S2, calculation and design of intelligent heat dissipation device of hydraulic oil tank
In the actual working process, because the system is changed under different working conditions and environments, the traditional hydraulic system is easy to have low high-temperature heat dissipation efficiency, and heat cannot be discharged in time, so that the temperature of oil is increased, and the improvement of the hydraulic oil tank by utilizing a phase-change material is proposed, so that the heat dissipation efficiency of the hydraulic oil tank is improved; as different phase change materials are different in heat transfer and heat dissipation performance, the selection of the appropriate phase change material and the appropriate structural parameters are important for the heat dissipation of the oil tank according to market research and reference of documents, so that the appropriate phase change material is screened according to the actual working temperature of the system and reasonably sealed to meet the heat dissipation requirement of the oil tank.
S201, calculating the heat productivity of a hydraulic system in a hydraulic oil tank, comprising
When the hydraulic system works, according to the law of conservation of capacity, except the effective power for driving the load, the rest of power loss does not work and is directly converted into heat; the heat is the sum of the three parts including the pump, the hydraulic valve and the pipeline; the pipeline pressure loss of the hydraulic system can be divided into two parts, namely, the on-way pressure loss and the local pressure loss of the pipeline, wherein the energy loss caused by the viscosity of the fluid is called the on-way pressure loss, and the energy loss caused by the sudden change of the cross section area of the pipeline is called the local pressure loss; because the analysis of the pressure loss of a concrete pipeline in engineering is complex, the heating power of the pipeline is generally determined to be 0.03-0.05 time of the total working heating power of the system;
the general work of a hydraulic system of a certain type of automobile crane is taken as an example for analysis, and the hydraulic system basically keeps unchanged in the circulation process of the getting-on part, so that the heat productivity of the hydraulic element in one circulation process of a hoisting mechanism, a rotary and loaded luffing mechanism is only calculated; the system has three hydraulic pumps with a rated rotation speed of 1800r/min, a rated pressure of 21MPa and power P1＝P2＝39.69kW，P3T is the working time of 28.35kW1＝t2＝t 360 min; the upper vehicle mechanism has 8 overflow valves, wherein the lifting mechanism has two overflow valves of 18.6MPa and one overflow valve of 18.5 MPa; the amplitude variation mechanism is provided with an overflow valve with the pressure of 9.8MPa and the pressure of 10 MPa; two 17MPa overflow valves of the slewing mechanism;
(1) calculation of heat production of hoisting mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure BDA0003343186400000151
in formula (7), P1Denotes the operating pressure, Q1Represents the flow rate of the pump, and η represents the total efficiency;
the heat production quantity of the hydraulic valve is as follows: h is12＝P2Q2＝105.273kw (8)
In formula (8), P2Indicating the regulated pressure value, Q, of the relief valve2Indicating flow through the overflow valve box;
the heat production of the pipeline is as follows: h is13The value of P is 1.3027kw, (0.03-0.05) is the heating power coefficient of the pipeline;
the total heat production capacity of the hoisting mechanism is as follows:
Figure BDA0003343186400000152
(2) calculation of heat production of slewing mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure BDA0003343186400000153
the heat production quantity of the hydraulic valve is as follows: h is22＝P2Q2＝37.422kw (11)
The heat production of the pipeline is as follows: h is23＝(0.03～0.05)P＝0.96kw (12)
The total heat production capacity of the slewing mechanism is as follows:
Figure BDA0003343186400000154
(3) calculation of heat production of luffing mechanism
Hydraulic pumpThe heat generation amount is:
Figure BDA0003343186400000155
the heat production quantity of the hydraulic valve is as follows: h is32＝P2Q2＝64.26kw (15)
The heat production of the pipeline is as follows: h is33＝(0.03～0.05)P＝0.877kw (16)
The total heat production capacity of the luffing mechanism is as follows:
Figure BDA0003343186400000161
according to the calculation result, the total heat production quantity of the hydraulic system is as follows:
W＝W1+W2+W3＝14.11297kwh (18)；
s202, calculating the heat dissipation capacity of a hydraulic system in a hydraulic oil tank
The heat generated by the hydraulic system finally reaches the oil tank through the pipeline, so the heat is mainly radiated by the oil tank and the pipeline; the pipeline has a simple structure and a large length-diameter ratio, hydraulic oil has short time for flowing through the pipeline, and the heat dissipation capacity is extremely small, so that the heat dissipation capacity is neglected, the heat dissipation capacity of the whole system is considered to be completed by the tank wall of the oil tank, the oil tank adopts a volume design with the largest heat dissipation area, the length-width-height ratio of the general oil tank is between 1: 1 and 1: 2: 3, and more effective heat dissipation areas can be provided;
(1) the side lengths of the hydraulic oil tank are respectively set as x, y and z, and according to the designed length-width-height ratio of the hydraulic oil tank, the side length model of the hydraulic oil tank is as follows:
Figure BDA0003343186400000162
when the function is used for solving A maximum, each side length is 1: 2: 3, so that A is 6.66V2/3；
(2) The volume of the oil tank of the hydraulic system is 280L, in order to reduce the installation volume of the oil tank as much as possible and simultaneously meet the nominal capacity condition of the oil tank, the volume of the oil tank is 200L, and the heat dissipation area is 2.3m2The heat balance temperature is 60 ℃, the environment initial temperature is 20 ℃, the system working time T is 4h, under the condition of good ventilation of the working environment, the heat dissipation coefficient of the material of the heat dissipation device is k, the area available for heat dissipation is A, the difference value between the environment temperature and the working temperature is delta T (less than or equal to 100 ℃), and then the total heat dissipation capacity of the hydraulic oil tank system is as follows: w is a1＝kA(ΔT)t＝3.174kwh (20)；
(3) Calculation of hydraulic system oil heat storage capacity
When the thermal balance state is not reached, a large amount of heat generated by the system is transmitted to the oil tank, the oil tank dissipates the heat, meanwhile, the hydraulic oil also begins to absorb the heat, the temperature of the oil liquid gradually rises, at the moment, the amount of heat absorbed by the oil liquid is related to the mass specific heat capacity and the temperature of the oil liquid, when the system reaches the thermal balance state, the hydraulic oil can not absorb the heat any more, and all the heat generated by the system dissipates the heat through the oil tank; in order to effectively calculate the heat storage capacity of the hydraulic oil, the volume of an oil tank adopted by the system is 200L, the oil capacity is 3-7 times of the flow per minute of a hydraulic pump, the oil capacity of the system is 150L through consulting data calculation, the common No. 10 aviation oil is taken as an example, the specific heat capacity c of the hydraulic oil is 2000J/(kg DEG C), and the density rho is 880kg/m3When the system reaches thermal equilibrium, the heat storage capacity of the oil liquid is as follows:
Δw＝cρV(ΔT)＝2.201kwh (21)
in the formula (21), c is the specific heat capacity of the hydraulic oil, ρ is the density of the hydraulic oil, and V is the volume capacity of the hydraulic oil tank;
(4) phase change material quality determination
According to the above formulas (18), (20) and (21), the heat production quantity, the heat dissipation quantity and the oil liquid heat storage quantity of the system can be obtained, the hydraulic system can normally work and must establish heat balance, when the hydraulic system starts to work, the oil temperature gradually rises, the hydraulic oil absorbs the heat generated by the system, meanwhile, the heat is dissipated through the oil tank, when the heat absorption quantity is equal to the heat dissipation quantity, the oil liquid temperature reaches a fixed value, at the moment, the hydraulic system reaches a heat balance state, and the system heat production quantity, the heat dissipation quantity and the oil liquid heat storage quantity have the following constraint relation:
Ht＝Nt+Lm+ΔW (22)
in formula (22), L is the latent heat of phase change of the phase change material;
selecting a crystalline hydrated salt Na according to the heat balance condition of the formula (22) and the calculation result2SO4·10H2O is the phase change material for heat dissipation, and the required mass is calculated as:
Figure BDA0003343186400000181
according to the calculation, the mass m of the phase-change material is 4.18kg, and since the volume of the phase-change material changes during the phase-change process, for safety, the volume of the phase-change material is calculated in a liquid state with a lower density:
Figure BDA0003343186400000182
(5) shape selection of phase change material
The heat of the hydraulic system is increased sharply after long-time working, in order to ensure that the effective heat dissipation of the oil tank enables the temperature of the hydraulic oil to be always in the normal range of 15-60 ℃, a phase-change material with the phase-change temperature in the range of 45-55 ℃ is selected, the unstable performance of the solid-solid phase-change material is considered, so the solid-liquid phase-change material with wider application range is selected, and the material with larger phase-change latent heat is selected due to the heat dissipation; comprehensive comparison and selection with Na2SO4·10H2O is a main body crystalline hydrated salt phase-change material which is used as a preparation material of the heat dissipation device;
(6) encapsulation of phase change materials
Since the phase change material is transformed in physical state during the phase change process, which may result in a change in area, it is necessary to encapsulate the phase change material with an encapsulation container, to protect the phase change material from failure due to leakage, and to conduct heat transfer and operation; the encapsulation mode of the phase-change material is roughly divided into three types, namely microcapsule encapsulation, integral heat exchanger and dispersed encapsulation; the material such as film and compound is used as the dispersed package of the packaging container, air is used as the heat conducting medium, the material can be processed on the fuel tank wall and the partition board of the fuel tank, the phase change material is packaged by a cuboid container, and the phase change material is welded and installed on the exterior of the container.
And S3, arranging a PT100 type thermal resistor in the hydraulic oil tank.
Through the design process of the intelligent temperature control system of the hydraulic oil tank, the intelligent temperature control system of the hydraulic oil tank is obtained: the intelligent temperature control system is arranged in the hydraulic oil tank 1 and comprises a heating device, a heat dissipation device and a temperature measurement feedback device;
the heating device comprises a heating partition plate and a heating unit encapsulated in the heating partition plate, wherein the heating unit consists of a plurality of B-100 type ceramic-based PTC thermistors which are mutually connected, the PTC thermistors are connected with a power supply anode and a power supply cathode, the power supply supplies electric energy to the PTC thermistors, meanwhile, leads of the PTC thermistors are connected with a solid-state relay and a temperature controller through copper tubes serving as lead pipes (good in heat conductivity, corrosion resistance and processability), and the PTC thermistors are controlled to work through the temperature controller; the heating partition plate is sealed by aluminum alloy, the aluminum alloy is adopted for facilitating heat conduction, a large amount of heat generated by the internal thermistor can be transferred to oil liquid through the aluminum alloy partition plate, and meanwhile, the heating partition plate is subjected to full-sealing treatment in order to prevent the oil liquid from flowing into the partition plate to cause the internal thermistor to fail to work normally due to the fact that the oil liquid is immersed in the heating partition plate to generate leakage;
the heat dissipation device is a heat dissipation unit encapsulated in a phase change material interlayer on the inner sides of the heat dissipation plates on the side wall and the bottom wall of the hydraulic oil tank, and the heat dissipation unit is made of Na2SO4·10H2O is made of a crystalline hydrated salt phase-change material as a main body, the heating partition plate 3 is fixed in a clamping groove type fixing mode in a non-spot welding mode in order to facilitate installation, fixing, overhauling and replacement of the heating partition plate 3, clamping grooves suitable for the requirements of the size and the depth are arranged on the bottom surface and the side surface of the oil tank, and the partition plate is placed into the clamping grooves to be fixed, so that looseness is avoided, maintenance and replacement are facilitated, and the processing amount is reduced;
the temperature measurement feedback device comprises a PT100 type thermal resistor, a temperature controller, a temperature sensor and a liquid crystal display screen, wherein the PT100 type thermal resistor is arranged at different positions and depths in the hydraulic oil tank and is connected with the temperature controller through an on-off control switch, the temperature controller controls the work of the heat dissipation unit by setting a target temperature and is connected with the liquid crystal display embedded in the upper cover of the oil tank through the temperature sensor to display the temperature of oil in real time; the temperature controller is an AI-519 type temperature controller, the precision is 0.3 grade, heating and refrigerating double output can be realized, a satisfactory control effect can be obtained without manually setting control parameters by carrying out self-tuning (AT) operation, the temperature control is stable, the use is simple, and the temperature control precision can be further improved; the temperature of the hydraulic oil is measured in real time through PT100 type thermal resistors arranged at different positions in the hydraulic oil tank, when the temperature of the hydraulic oil is about to reach a preset temperature value, the temperature controller enables the heating device to be powered off and stops heating immediately through the on-off control switch, and the temperature of the hydraulic oil is controlled to accurately reach a set value; when the temperature of the hydraulic oil is affected by the external working environment and is lower than the normal working temperature range of the hydraulic oil, the heating device is awakened by the controller, the heating unit heats the hydraulic oil again, the oil temperature rises to reach the normal working range, the whole process can be accurately heated to a preset specific temperature value by controlling the heating device, constant temperature control is realized, and the temperature of the hydraulic oil is always in the normal working range.
Preferably, in order to ensure the heat dissipation effect, the heat dissipation unit is encapsulated in a phase change microcapsule in a phase change material interlayer on the side wall of the hydraulic oil tank, and the phase change material is microencapsulated, so that the reactivity of the phase change material with the outside can be effectively reduced, the heat transfer area is enlarged, and the heat transfer rate is increased; meanwhile, the heat dissipation unit is subjected to combined type packaging through the heat dissipation plate, the phase change microcapsules are further subjected to separation packaging in the frame partition plate and the bottom plate of the oil tank, the side frame partition plate and the bottom plate are mutually isolated, and due to the coating property of the shell wall material, the problems of volume change and leakage of the solid-liquid phase change material during phase change are solved, and the phenomena of supercooling and phase separation in the phase change process of the phase change material are avoided; the composite package is characterized in that solid-liquid microcapsule heat dissipation materials are mainly used in the side frame partition plates, the heat dissipation materials installed in the bottom plate are solid-solid phase change materials, the two heat dissipation units have different action modes, the phase change microcapsules are separately packaged in the frame partition plates and the bottom plate of the oil tank, and the side frame partition plates are mutually isolated from the bottom plate.
Preferably, the non-spot welding and the clamping groove type installation are that one section of clamping groove is respectively installed at the bottom and the side edge of the oil tank, the heating partition plate is placed in the clamping groove, the clamping groove can fix the partition plate and change the position of the partition plate, the partition plate is convenient to detach, maintain and replace, and the workload and the cost are reduced.
Preferably, in the heating system, the PTC electric heating circuit mainly comprises components such as a PTC, a heating relay temperature controller, a temperature control switch, a display, a switch and the like, the PTC thermistor adopts a parallel constant-voltage working mode, and the working principle diagram is shown in fig. 9; when the temperature control switch is closed, the PTC starts working, the temperature of the oil liquid starts rising, and when the measured oil liquid is higher than 40 ℃, the temperature controller controls the temperature control switch to be switched off, the switch connected in parallel with the temperature control switch is switched on, the current is increased, the PTC thermistor is controlled not to be heated any more, the temperature of the oil liquid reaches the required working condition range at the moment, and the working flow is shown in figure 10;
the circuit design and temperature control method has the following two advantages: 1. the heating mode can effectively prolong the service life of the ceramic-based PTC thermistor, and 2, the heating temperature is accurately controlled, and the heating efficiency is improved.
The intelligent temperature control system of the hydraulic oil tank has the following main advantages:
(1) based on the ceramic-based PTC thermosensitive material, the oil liquid can be accurately heated in a low-temperature environment, the heating time is short, the temperature control precision is high, the self-adaptive temperature control can be realized, and the quick starting of the hydraulic equipment is met; an electric heating partition plate is adopted, so that the oil liquid can be prevented from deteriorating due to local high temperature in the oil liquid heating process;
(2) with Na2SO4·10H2O is a main body crystalline hydrated salt phase-change material, the oil tank is higher in heat dissipation efficiency after being packaged in the oil tank, and the working performance of a hydraulic system is prevented from being influenced by overhigh oil temperature;
(3) the oil tank integrated design with low-temperature heating and high-temperature heat dissipation is carried out, the temperature control function is obvious, and the oil tank integrated design is suitable for wide-temperature-range application occasions.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (10)

1. The utility model provides a hydraulic tank intelligence temperature control system which characterized in that: the intelligent temperature control system is arranged in the hydraulic oil tank and comprises a heating device, a heat dissipation device and a temperature measurement feedback device;
the heating device comprises a heating partition plate and a heating unit packaged in the heating partition plate, the heating partition plate is sealed by aluminum alloy, and the heating unit is connected with a power supply and a temperature measurement feedback device;
the heat dissipation device is a heat dissipation unit encapsulated in a phase change material interlayer on the inner sides of the heat dissipation plates on the side wall and the bottom wall of the hydraulic oil tank, and the heat dissipation unit is made of Na2SO4·10H2O is prepared from a main body crystalline hydrous salt phase-change material;
the temperature measurement feedback device comprises a PT100 type thermal resistor, a temperature controller, a temperature sensor and a liquid crystal display screen, wherein the PT100 type thermal resistor is installed at different positions and depths in a hydraulic oil tank and is connected with the temperature controller through an on-off control switch, the temperature controller controls the work of a heat dissipation unit through setting a target temperature, and the temperature sensor is connected with the liquid crystal display embedded in the upper cover of the oil tank to display the temperature of oil liquid in real time.
2. The intelligent temperature control system of the hydraulic oil tank as claimed in claim 1, wherein: the heating unit consists of a plurality of B-100 type ceramic-based PTC thermistors which are connected with each other, the PTC thermistors are connected with a power supply anode and a power supply cathode, and the power supply supplies electric energy to the PTC thermistors; meanwhile, a lead of the PTC thermistor is connected with the solid-state relay and the temperature controller through a copper tube, and the PTC thermistor is controlled to work through the temperature controller.
3. The intelligent temperature control system of the hydraulic oil tank as claimed in claim 1, wherein: the encapsulation form of the heat dissipation unit in the phase-change material interlayer of the side wall of the hydraulic oil tank is phase-change microcapsules, the heat dissipation plate is installed in the clamping grooves in the bottom surface and the side surface of the oil tank in a non-spot welding and clamping groove type mode, the heat dissipation unit is encapsulated in a combined type through the heat dissipation plate, the phase-change microcapsules are separately encapsulated in the frame partition plate and the bottom plate of the oil tank, and the side frame partition plate and the bottom plate are isolated from each other.
4. The intelligent temperature control system of the hydraulic oil tank as claimed in claim 3, wherein: the side frame partition is internally provided with a solid-liquid microcapsule heat dissipation material, and the bottom plate is internally provided with a solid-solid phase change heat dissipation material.
5. The intelligent temperature control system of the hydraulic oil tank as claimed in claim 1, wherein: the temperature controller is an AI-519 type temperature controller, the precision is 0.3 level, and double output of heating and refrigerating can be realized.
6. The design method of the intelligent temperature control system of the hydraulic oil tank according to claim 1, characterized in that: the design method comprises the steps of
S1, designing an intelligent heating device of a hydraulic oil tank;
s101, establishing resistance value models of the PTC thermistors at different environmental temperatures;
s102, calculating the power of a heating device in the hydraulic oil tank under the condition of not considering the heat dissipation of the oil tank;
s103, determining the size of the heating device according to the obtained power design of the heating device;
s2, designing an intelligent heat dissipation device of the hydraulic oil tank;
s201, calculating the heating value of a hydraulic system in a hydraulic oil tank;
s202, calculating the heat dissipation capacity of a hydraulic system in a hydraulic oil tank;
and S3, arranging a PT100 type thermal resistor in the hydraulic oil tank.
7. The design method of the intelligent temperature control system of the hydraulic oil tank according to claim 6, characterized in that: the process of establishing the resistance value model of the PTC thermistor at different environmental temperatures in step S101 includes
(1) Placing a B-100 type ceramic matrix PTC thermistor in a constant temperature water tank, measuring a corresponding resistance value by adjusting the water temperature, measuring the temperature and the numerical value of the resistance by using a temperature measuring instrument and a resistance measuring instrument, and recording data to obtain a resistance-temperature characteristic curve of the thermistor;
(2) the Curie temperature of the B-100 type ceramic matrix PTC thermistor can be obtained through a resistance-temperature characteristic curve to be 60 ℃, and when the temperature of the PTC thermistor is lower than 60 ℃, the resistivity is about 3900Q cm and is always a fixed value; when the temperature of the PTC thermistor is above 60 ℃, the temperature is increased to 80 ℃, and the resistivity of the PTC thermistor is increased exponentially;
(3) fitting the data of the resistance value and the temperature of the B-100 type ceramic-based PTC thermistor at 60 ℃ on a computer to obtain:
ρ(PTC)＝10β+BT (1)
in the formula (1), β represents a characteristic parameter relating to resistance; b represents the slope of the resistance-temperature curve;
(4) the resistance value can be expressed as:
Figure FDA0003343186390000031
in the formula (2), S represents the cross-sectional area of the PTC thermistor, and D represents the thickness of the PTC thermistor;
the temperature coefficient of the PTC thermistor can be obtained as:
Figure FDA0003343186390000032
in the formula (3), T represents the temperature of the PTC thermistor, and the resistance value of the PTC thermistor at different environmental temperatures can be calculated by the formula (3).
8. The design method of the intelligent temperature control system of the hydraulic oil tank according to claim 6, characterized in that: the calculation process of the heating device power and the heating device size in the hydraulic oil tank described in the step S102 and the step S103 includes
(1) Calculation of heating device power in hydraulic tank
Setting the power of the heating device as Pj, the effective volume in the hydraulic oil tank as V, and the ambient temperature of the oil tank as t1The preset temperature t for heating the hydraulic oil2The heating time is T, the specific heat capacity of the hydraulic oil is rho, the density of the hydraulic oil is C, and the calculation model for establishing the power required by the heating device is as follows:
Figure FDA0003343186390000041
according to the formula (4), under the condition that the heat dissipation of the oil tank is not considered, the power required by the heating device can be obtained, the power of the heating device is further determined, and a ceramic-based PTC thermistor with the model number of B-100 is used as a heating element;
(2) design of heating device size
Setting the heating energy of the required heating device as Q, the heat transfer coefficient as K, the surface area of the required heating device as A, and the temperature change value of the hydraulic oil as delta t, the obtained surface area of the heating device is as follows:
Q＝KAΔt (5)
from the formula (5), it is possible to obtain
A＝0.12m2 (6)
A plurality of B-100 type ceramic-based PTC thermistors are connected and encapsulated by an aluminum alloy shell to form a heating clapboard which is arranged in a hydraulic oil tank.
9. The design method of the intelligent temperature control system of the hydraulic oil tank according to claim 6, characterized in that: the calculation process of the calorific value of the hydraulic system in the hydraulic oil tank in the step S201 includes
(1) Calculation of heat production of hoisting mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure FDA0003343186390000051
in formula (7), P1Denotes the operating pressure, Q1Represents the flow rate of the pump, and η represents the total efficiency;
the heat production quantity of the hydraulic valve is as follows: h is12＝P2Q2 (8)
In formula (8), P2Indicating the regulated pressure value, Q, of the relief valve2Indicating flow through the overflow valve box;
the heat production of the pipeline is as follows: h is13P is (0.03-0.05), and (0.03-0.05) is the heating power coefficient of the pipeline;
the total heat production capacity of the hoisting mechanism is as follows:
Figure FDA0003343186390000052
(2) calculation of heat production of slewing mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure FDA0003343186390000053
the heat production quantity of the hydraulic valve is as follows: h is22＝P2Q2 (11)
The heat production of the pipeline is as follows: h is23＝(0.03～0.05)P (12)
The total heat production capacity of the slewing mechanism is as follows:
Figure FDA0003343186390000054
(3) calculation of heat production of luffing mechanism
The heat generation capacity of the hydraulic pump is as follows:
Figure FDA0003343186390000055
the heat production quantity of the hydraulic valve is as follows: h is32＝P2Q2 (15)
The heat production of the pipeline is as follows: h is33＝(0.03～0.05)P (16)
Total heat production of the luffing mechanism:
Figure FDA0003343186390000056
according to the calculation result, the total heat production quantity of the hydraulic system is as follows:
W＝W1+W2+W3 (18)。
10. the design method of the intelligent temperature control system of the hydraulic oil tank according to claim 6, characterized in that: the calculation process of the heat dissipation capacity of the hydraulic system in the hydraulic oil tank in step S202 includes
(1) The side lengths of the hydraulic oil tank are respectively set as x, y and z, and according to the designed length-width-height ratio of the hydraulic oil tank, the side length model of the hydraulic oil tank is as follows:
Figure FDA0003343186390000061
when the function is used for solving A maximum, each side length is 1: 2: 3, so that A is 6.66V2/3；
(2) If the heat dissipation coefficient of the material of the heat dissipation device is k, the area available for heat dissipation is a, and the difference between the ambient temperature and the working temperature is Δ T, the total heat dissipation capacity of the hydraulic oil tank system is as follows:
w1＝kA(ΔT)t (20)
(3) calculating the oil heat storage capacity of the hydraulic system:
Δw＝cρV(ΔT) (21)
in the formula (21), c is the specific heat capacity of the hydraulic oil, ρ is the density of the hydraulic oil, and V is the volume capacity of the hydraulic oil tank;
(4) phase change material quality determination
According to the above formulas (18), (20) and (21), the heat production quantity, the heat dissipation quantity and the oil liquid heat storage quantity of the system can be obtained, when the heat absorption quantity is equal to the heat dissipation quantity, the oil liquid temperature reaches a fixed value, the hydraulic system reaches a thermal equilibrium state, and the system heat production quantity, the heat dissipation quantity and the oil liquid heat storage quantity have the following constraint relation:
Ht＝Nt+Lm+ΔW (22)
in formula (22), L is the latent heat of phase change of the phase change material;
selecting a crystalline hydrated salt Na according to the heat balance condition of the formula (22) and the calculation result2SO4·10H2O is the phase change material for heat dissipation, and the required mass is calculated as:
Figure FDA0003343186390000062
because the volume of the phase-change material changes along with the phase-change material in the phase-change process, for the sake of safety, the volume of the phase-change material is obtained by calculating in a liquid state with smaller density:
Figure FDA0003343186390000071
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Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6196395A (en) * 1984-10-18 1986-05-15 Matsushita Electric Ind Co Ltd Heat transfer device
US5719332A (en) * 1994-09-28 1998-02-17 Vdo Adolf Schindling Ag Process and system for operating a level sensor
CN202391870U (en) * 2011-12-05 2012-08-22 天津市天锻液压有限公司 Energy-saving oil temperature control device
CN103557206A (en) * 2013-11-09 2014-02-05 中联重科股份有限公司 Rotating speed control method and device for cooling fan in hydraulic system
US20140260229A1 (en) * 2013-03-14 2014-09-18 Allison Transmission, Inc. System and method for feed forward control of a hydraulic control system of a transmission
US20150096288A1 (en) * 2013-07-09 2015-04-09 The Boeing Company Systems and Methods for Heat Balance and Transport for Aircraft Hydraulic Systems
CN206190643U (en) * 2016-09-30 2017-05-24 河北高达电子科技有限公司 Hydraulic oil temperature control device
CN110259768A (en) * 2019-06-28 2019-09-20 三一重机有限公司 The temperature control device of hydraulic system
CN110346246A (en) * 2019-07-22 2019-10-18 中国人民解放军火箭军工程大学 A kind of shock processing method improving hydraulic oil low temperature fluidity
CN209671326U (en) * 2018-04-24 2019-11-22 江苏亿都智能特种装备有限公司 A kind of hydraulic oil container Oil-temperature control system
CN111332095A (en) * 2020-04-07 2020-06-26 孝感华工高理电子有限公司 Heating device and apparatus comprising said heating device
CN112797055A (en) * 2021-01-28 2021-05-14 宝鸡中车时代工程机械有限公司 Hydraulic oil temperature control system

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6196395A (en) * 1984-10-18 1986-05-15 Matsushita Electric Ind Co Ltd Heat transfer device
US5719332A (en) * 1994-09-28 1998-02-17 Vdo Adolf Schindling Ag Process and system for operating a level sensor
CN202391870U (en) * 2011-12-05 2012-08-22 天津市天锻液压有限公司 Energy-saving oil temperature control device
US20140260229A1 (en) * 2013-03-14 2014-09-18 Allison Transmission, Inc. System and method for feed forward control of a hydraulic control system of a transmission
US20150096288A1 (en) * 2013-07-09 2015-04-09 The Boeing Company Systems and Methods for Heat Balance and Transport for Aircraft Hydraulic Systems
CN103557206A (en) * 2013-11-09 2014-02-05 中联重科股份有限公司 Rotating speed control method and device for cooling fan in hydraulic system
CN206190643U (en) * 2016-09-30 2017-05-24 河北高达电子科技有限公司 Hydraulic oil temperature control device
CN209671326U (en) * 2018-04-24 2019-11-22 江苏亿都智能特种装备有限公司 A kind of hydraulic oil container Oil-temperature control system
CN110259768A (en) * 2019-06-28 2019-09-20 三一重机有限公司 The temperature control device of hydraulic system
CN110346246A (en) * 2019-07-22 2019-10-18 中国人民解放军火箭军工程大学 A kind of shock processing method improving hydraulic oil low temperature fluidity
CN111332095A (en) * 2020-04-07 2020-06-26 孝感华工高理电子有限公司 Heating device and apparatus comprising said heating device
CN112797055A (en) * 2021-01-28 2021-05-14 宝鸡中车时代工程机械有限公司 Hydraulic oil temperature control system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
关标;冯永保;李淑智;王杰;: "基于相变材料的油箱换热板散热仿真与研究", 机床与液压 *

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