CN105806433B - Probe removes the method and device of liquid deicing in a kind of gas medium flow measurement - Google Patents
Probe removes the method and device of liquid deicing in a kind of gas medium flow measurement Download PDFInfo
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- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
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Abstract
The embodiment of the invention discloses the method and devices that probe in a kind of gas medium flow measurement removes liquid deicing.Wherein, probe removes the method for liquid deicing the following steps are included: S1. measurement gas Current Temperatures and flow in gas medium flow measurement；S2. liquid deicing heated current is removed according to the temperature of measurement and flow rate calculation；S3. according to heating time is preset, liquid deicing heated current is removed according to described, controls being heated from thermal probe for flowmeter.The present invention removes liquid deicing heating stepses by introducing in existing gas flow measurement method, realizes in measurement process and handle except liquid deicing to from thermal probe, and then improves the precision of the flow measurement in containing liquid gas medium containing ice.In addition, the present invention also provides a kind of method for calculating and removing liquid deicing heated current, the calculation method is simple and effective, it is ensured that except time efficiency and energy efficiency with higher in liquid deicing heating process.
Description
Technical Field
The invention relates to the technical field of instruments and meters, in particular to a method and a device for removing liquid and ice of a probe in gas medium flow measurement.
Background
Thermal gas mass flowmeters are instruments that measure the flow of gas using the principle of thermal diffusion. The flow measurement principle of the thermal gas mass flowmeter which is common at present mainly comprises: constant temperature difference principle, constant power principle and constant ratio principle. The more advanced demerma type mass flowmeter usually adopts the constant ratio principle to measure the gas flow. The thermal gas mass flowmeter comprises two thermal resistance sensors with positive temperature coefficient, one of which is a Resistance Temperature Detector (RTD) for supplying heat to the fluid and the resistance value is RH(ii) a The other is a reference RTD for measuring the actual temperature of the fluid in real time, with a resistance value RC. RTD is simply called thermal resistor, which is actually a special wire whose resistance changes with temperature, and typically RTD materials include copper, platinum, nickel and nickel/iron alloys. The operating principle of the flowmeter for measuring the gas flow rate is that the temperature of the electric heating RTD is controlled by adopting a constant ratio heating method as disclosed in the patent US6450024B1, so that the resistance value R of the electric heating RTD is enabled to beHResistance value R of reference RTDCIs kept constant, i.e. gamma-RH/RCIs a constant. Therefore, when fluid flows through the current-carrying heating RTD, the fluid can carry away the generated heat to lower the resistance value of the fluid, and in order to keep a constant ratio, the heating current of the current-carrying heating RTD can be increased to compensate the heat carried away by the fluid; the larger the flow rate, the more heat the fluid carries away, and the larger the heating current of the energized RTD. The heating current of the current heating RTD is in one-to-one correspondence with the fluid flow, so that the heating current is measuredThe flow value allows the fluid flow to be calculated.
For the above thermal mass flowmeter, when the measured liquid is dry and pure gas, the measurement effect is good, and the reading is very stable. However, if the measured gas contains liquid or the temperature of the gas is too low, the liquid medium is often attached to the surface of the RTD heated during measurement due to the limited heating performance of the RTD heated during measurement, and the RTD can even freeze at low temperature, which affects the heat removal capability of the gas flow medium, and further affects the accuracy of gas flow measurement, and even cannot measure.
Disclosure of Invention
The technical problem to be solved by the embodiment of the invention is to provide a method and a device for removing liquid and ice from a probe in the flow measurement of a gas medium, aiming at the defect that the conventional thermal gas mass flowmeter cannot normally measure when the RTD probe is frozen due to the fact that liquid drops are contained in the measured gas medium or the gas temperature is too low.
In order to solve the above technical problem, an embodiment of the present invention provides a method for measuring a gas flow, including the following steps:
s1, measuring the current temperature and flow of gas;
s2, calculating a liquid and ice removing heating current according to the measured temperature and flow;
and S3, controlling a self-heating probe of the flowmeter to heat according to the preset heating time and the liquid and ice removing heating current.
Preferably, the method for removing liquid and ice from the probe in the gas medium flow measurement further comprises the following steps:
and S4, switching to a normal measurement mode and measuring the current flow after waiting for the preset heat balance time.
Preferably, in the step S2, the liquid and ice removing heating current is calculated by the following formula:
wherein, IheatingHeating current for removing liquid and ice ImaxFor maximum heating current of the heating circuit, I0Heating current at zero flow at the present temperature, MFFor the currently measured flow, MRIs the flowmeter range.
Preferably, after the step S1, the method further includes the steps of:
s5, judging whether the liquid removing and deicing functions of the probe are started or not, if so, turning to the step S2; otherwise, the step S1 is returned to.
Preferably, the steps S2, S3, and S4 are performed cyclically during continuous measurement.
Correspondingly, the invention also provides a thermal gas mass flowmeter, comprising: the device comprises a flow calculation module, a control module, a sensor module and a liquid and ice removing and heating current calculation module, wherein the sensor module comprises a self-heating probe for heating and a temperature probe for measuring temperature; wherein,
the control module is respectively connected to the flow calculation module, the sensor module and the liquid and ice removal heating current calculation module;
the flow calculation module calculates the current flow according to the data measured by the sensor module, the liquid and ice removing heating current calculation module calculates the liquid and ice removing heating current according to the measured flow and the temperature measured by the temperature probe, and the control module controls the self-heating probe to heat according to the preset heating time and the liquid and ice removing heating current so as to remove liquid and/or ice blocks on the self-heating probe.
Preferably, the device for removing liquid and ice from the probe in gas medium flow measurement further comprises a mode switching module; the mode switching module is used for sending a working mode switching signal to the control module, and the control module controls the device for removing liquid and ice of the probe in the gas medium flow measurement to switch between a liquid and ice removing heating mode and a flow measurement mode according to the working mode switching signal; when the liquid and ice removing heating mode is switched to the flow measurement mode, the control module controls the probe liquid and ice removing device in the gas medium flow measurement to wait for the preset heat balance time and then carry out flow measurement.
Preferably, the liquid and ice removing heating current calculating module calculates the liquid and ice removing heating current by the following formula:
wherein, IheatingHeating current for removing liquid and ice ImaxFor maximum heating current of the heating circuit, I0Heating current at zero flow at the present temperature, MFFor the currently measured flow, MRIs the flowmeter range.
Preferably, the device for removing liquid and ice of the probe in the gas medium flow measurement further comprises a liquid and ice removing function setting module and a liquid and ice removing function determining module; wherein
The liquid and ice removing function setting module is used for setting whether to start a liquid and ice removing function;
and the liquid and ice removing function judging module is used for judging whether the liquid and ice removing function is started.
Preferably, the control module is further used for controlling the self-heating probe to be heated circularly according to the liquid and ice removing heating current according to a preset period in the continuous measurement process.
The embodiment of the invention has the following beneficial effects: the invention realizes the liquid and ice removing treatment of the self-heating probe in the measuring process by introducing the liquid and ice removing heating step in the existing gas flow measuring method, thereby improving the flow measuring precision in the liquid-containing ice-containing gas medium. And a specific calculation method of the liquid removing and deicing heating current is also provided, so that the liquid removing and deicing heating process has higher time efficiency and energy efficiency.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a flow chart of a method for removing liquid and ice from a probe in a gas medium flow measurement according to a first embodiment of the present invention;
FIG. 2 is a flow chart of a second embodiment of a method for measuring the flow of a gaseous medium provided by the present invention;
FIG. 3 is a flow chart of a third embodiment of a method for measuring the flow of a gaseous medium provided by the present invention;
FIG. 4 is a block diagram illustrating a probe liquid removing and deicing device for measuring flow of a gas medium according to a fourth embodiment of the present invention;
fig. 5 is a block diagram of a probe liquid removing and deicing device in the gas medium flow measurement according to a fifth embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
Referring to fig. 1, fig. 1 is a flow chart of a probe liquid removing and deicing method in gas medium flow measurement according to a first embodiment of the present invention. As shown in fig. 1, the method for removing liquid and ice from a probe in gas medium flow measurement in the present embodiment includes steps S1 to S3:
s1, measuring the current temperature and flow of gas;
the temperature and flow rate measured at step S1 are the current temperature and initial flow rate of the gas for each individual measurement. The flow measurement principle in the present invention mainly includes a constant ratio principle, a constant power principle, a constant temperature difference principle or other feasible measurement principles. Wherein the constant ratio heating method controls the temperature of the RTD to make the resistance R of the RTD to generate heatHResistance value R of reference RTDCIs kept constant, i.e. gamma-RH/RCIs a constant. Therefore, when fluid flows through the current-carrying heating RTD, the fluid can carry away the generated heat to lower the resistance value of the fluid, and in order to keep a constant ratio, the heating current of the current-carrying heating RTD can be increased to compensate the heat carried away by the fluid; the larger the flow rate, the more heat the fluid carries away, and the larger the heating current of the energized RTD. The heating current of the current-carrying heating RTD and the fluid flow have a one-to-one correspondence relationship, so the fluid flow can be calculated by measuring the heating current value. The product of the constant power principle has one more heater than the product of the constant ratio and constant temperature difference principle. The platinum resistor is heated by applying a constant power to the heater, and the temperature difference between the heated platinum resistor and the unheated platinum resistor is maximum when the medium is in a static state. As the medium flows, the temperature difference decreases. The change in flow is obtained by measuring the change in temperature difference between the two RTDs. The heating mode of constant temperature difference is that one platinum resistor is heated first to make it higher than the platinum resistor which is not heated by a constant temperatureAnd (4) degree. Along with the flowing of the medium, the temperature of the heated platinum resistor is reduced due to heat dissipation, the platinum resistor is fed back to the main controller through the feedback circuit, the temperature difference of the platinum resistor is kept to be a constant value by increasing the current (or voltage) of the heater, and then the change value of the flow is obtained by detecting the change current (or voltage).
S2, calculating a liquid and ice removing heating current according to the measured temperature and flow;
in general, the amount of heat generated from the self-heating RTD resistor is limited, regardless of the constant ratio principle, the constant power principle, or the constant temperature difference principle. For humidified gases, especially those humidified at low temperatures, the self-heating RTD is very susceptible to liquid and even ice formation. Especially for the product based on the constant temperature difference principle, the heat generation amount of the self-heating RTD resistor is extremely low when the gas temperature is very low. To remove the liquid or ice from the hot RTD probe, a large current is required to flow through the RTD probe to generate a large amount of heat to remove the liquid and ice. In a preferred embodiment of the present invention, the liquid and ice removal heating current flowing through the autothermal probe is calculated by the following formula:
wherein, IheatingHeating current for removing liquid and ice; i ismaxThe maximum heating current of the heating circuit is related to hardware parameters of the heating circuit, and is a fixed value for each designed heating circuit; i is0Heating current at zero flow at the present temperature, I0The relationship with temperature is prior art and will not be described in detail herein; mFIs the current measured flow; mRIs the flowmeter range. As can be seen from the above formula, the heating current for liquid and ice removal calculated in the present application varies with the measured flow rate. The higher the flow rate, the higher the heating current for de-icing and de-icing to ensure that liquid and/or ice from the probe is removed in the shortest possible time. That is, the present invention providesThe liquid and ice removing heating current can ensure higher time efficiency and energy efficiency of liquid and ice removing.
S3, controlling a self-heating probe of the flowmeter to heat according to preset heating time and the liquid and ice removing heating current;
in the invention, the user can preset the time for heating the self-heating probe to remove the liquid and ice so as to ensure that the liquid drops and/or ice blocks on the self-heating probe are sufficiently removed.
The embodiment provides a method for removing liquid and ice on a probe in gas medium flow measurement, which can effectively remove liquid and/or ice on the surface of the probe in flow measurement. And a specific calculation method of the liquid removing and deicing heating current is also provided, so that the liquid removing and deicing heating process has higher time efficiency and energy efficiency.
Referring to fig. 2, fig. 2 is a flow chart of a flow measurement method of a gas medium according to a second embodiment of the present invention. As shown in fig. 2, compared with the first embodiment, the gas flow measuring method of the present embodiment adds a determination step between step S1 and step S2 of the first embodiment, adds a flow measuring step after step S3 of the first embodiment, and reorders the steps, thereby forming the unique gas medium flow measuring method with probe liquid removing and deicing functions of the present embodiment.
In the present embodiment, a newly added determination step S2 is used to determine whether the flow meter has started the liquid and ice removal function. If the power supply is started, further calculating the liquid and ice removing heating current; and if the current flow and the temperature are not started, the measured current measured flow and temperature are directly output to the display module.
In this embodiment, the newly added flow measurement step S4 is: and switching to a normal measurement module and measuring the current flow after waiting for the preset heat balance time. After the self-heating probe is heated for a preset heating time by the fluid removing and deicing heating current, the flow meter can automatically switch the working mode from the previous fluid removing and deicing heating mode to the normal measurement mode. And after the mode is switched, stopping removing liquid and deicing for heating, waiting for preset heat balance time, and measuring flow after heat balance between the self-heating probe and the gas is achieved. Since the initially measured flow rate is inaccurate, the flow meter can accurately measure the flow rate of the gas after the liquid and ice removing heating process of step S3. It should be understood that, in this step, the flow measurement method is adopted in accordance with the flow measurement method in step S1, and the measurement principle is a constant ratio principle, a constant power principle, a constant temperature difference principle or other feasible measurement principles. After the liquid and ice removing treatment, the measured gas flow value is accurate and stable.
In this embodiment, a user may preset whether to start the liquid and ice removing function, or may start or stop the liquid and ice removing function according to actual conditions during use. Other steps are the same as those of the first embodiment, and will not be described again.
By implementing the embodiment, a diversified choice can be provided for a user, so that the liquid and ice removing function can be started by the user under the condition of requirement. Therefore, the gas flow can be directly measured by using the traditional method under the condition that the liquid and ice removing functions are not required to be started, the time and the energy are saved, and the cost is reduced. In addition, the present embodiment provides a new method of measuring the flow of a gaseous medium that removes liquid and/or ice from the heater probe during the measurement process, thereby allowing more accurate flow measurements of the liquid-containing gaseous medium, even at low temperatures.
Referring to fig. 3, fig. 3 is a flow chart of a gas medium flow measuring method according to a third embodiment of the present invention. As shown in fig. 3, this embodiment further adds a cycle to the second embodiment. That is, in the actual use process, the measurement is a continuous process, in the continuous measurement process, the self-heating probe may be stained with liquid drops or frozen again, and in order to realize accurate measurement, the process of calculating the liquid removing and deicing heating current, the liquid removing and deicing heating, waiting for the heat balance and measuring the flow needs to be continuously and circularly executed. In such a cycle measurement process, the measured current flow of the gas is the initial measured flow in the next cycle, and the initial measured flow is input into the deicing and fluid removal heating current calculation module as a parameter for calculating the deicing and fluid removal heating current. The temperature probe is used for measuring the temperature of the gas in real time all the time and sending the measured temperature to the control module so that other modules can call the temperature parameters conveniently.
In the invention, the liquid removing, deicing and heating time, the waiting heat balance time and the liquid removing, deicing and heating interval time (which is approximately the time for continuously measuring the flow) can be preset according to the actual situation or can be adjusted at any time in the measuring process. In a preferred embodiment provided by the invention, the time range of liquid removing, deicing and heating is 0-20 s, the waiting heat balance time is 0-99 s, and the time interval between liquid removing, deicing and heating is 2-64 min (2-64 min).
It should be understood that the gas flow measurement method provided in the present embodiment may not include the determination step in the second embodiment.
By implementing the embodiment, the measurement accuracy can be continuously ensured in long-time continuous measurement, and the influence on the measurement accuracy due to the fact that the self-heating probe is again stained with liquid drops or frozen in the measurement process can be avoided.
Referring to fig. 4, fig. 4 is a block diagram of a probe liquid removing and deicing device for measuring flow of a gas medium according to a fourth embodiment of the present invention. As shown in fig. 4, the device for removing liquid and ice from a probe in gas medium flow measurement provided by this embodiment includes: the device comprises a control module 1, a sensor module 2, a liquid and ice removing heating current calculating module 3 and a flow calculating module 4. Wherein the sensor module 2 comprises a self-heating probe 21 and a temperature probe 22. The control module 1 is respectively connected to the flow calculation module 4, the sensor module 2 and the liquid and ice removing heating current calculation module 3. The self-heating probe 21 and the temperature probe 22 are two thermistors with positive temperature coefficients. The self-heating probe 21 is connected to the sensor excitation module so that current flows through the self-heating probe 21, thereby generating heat.
Flow measuring element in the present inventionThe principle mainly comprises a constant ratio principle, a constant power principle and a constant temperature difference principle. Wherein the constant ratio heating method controls the temperature of the RTD to make the resistance R of the RTD to generate heatHResistance value R of reference RTDCIs kept constant, i.e. gamma-RH/RCIs a constant. Therefore, when fluid flows through the current-carrying heating RTD, the fluid can carry away the generated heat to lower the resistance value of the fluid, and in order to keep a constant ratio, the heating current of the current-carrying heating RTD can be increased to compensate the heat carried away by the fluid; the larger the flow rate, the more heat the fluid carries away, and the larger the heating current of the energized RTD. The heating current of the current-carrying heating RTD and the fluid flow have a one-to-one correspondence relationship, so the fluid flow can be calculated by measuring the heating current value. The product of the constant power principle has one more heater than the product of the constant ratio and constant temperature difference principle. The platinum resistor is heated by applying a constant power to the heater, and the temperature difference between the heated platinum resistor and the unheated platinum resistor is maximum when the medium is in a static state. As the medium flows, the temperature difference decreases. The change in flow is obtained by measuring the change in temperature difference between the two RTDs. The heating mode of constant temperature difference is that a platinum resistor is heated first, so that the temperature of the platinum resistor is higher than that of the platinum resistor which is not heated by a constant temperature. Along with the flowing of the medium, the temperature of the heated platinum resistor is reduced due to heat dissipation, the platinum resistor is fed back to the main controller through the feedback circuit, the temperature difference of the platinum resistor is kept to be a constant value by increasing the current (or voltage) of the heater, and then the change value of the flow is obtained by detecting the change current (or voltage).
Generally, the amount of heat generated by the self-heating probe is limited, regardless of the constant ratio principle, the constant power principle, or the constant temperature difference principle. For humidified gases, especially gases humidified at low temperatures, the self-heating probe is prone to being contaminated with liquid and even freezing. Especially for the product based on the constant temperature difference principle, when the gas temperature is very low, the heat productivity of the self-heating probe is very low.
In order to remove liquid or ice blocks on the self-heating probe 21 during or before measurement, the probe liquid-removing and ice-removing device in the gas medium flow measurement provided by the application has the following working principle:
the flow calculation module 4 acquires data measured by the sensor module 2 through the control module 1, the measured initial data comprises gas medium temperature and heating current value, and the current flow is calculated according to the measured data; the liquid removing and deicing heating current calculation module calculates liquid removing and deicing heating current by acquiring the calculated flow and the temperature measured by the temperature probe through the control module 1, and sends the calculated liquid removing and deicing heating current to the control module 1, the control module 1 further controls the heating current of the self-heating probe 21 to be equal to the calculated liquid removing and deicing heating current, and controls the heating time of the self-heating probe 21 according to the preset heating time, so that the self-heating probe 21 is strongly heated by a stronger current to remove liquid and/or ice blocks on the self-heating probe 21.
In a preferred embodiment of the present invention, the liquid-removing and deicing heating current calculation module calculates the liquid-removing and deicing heating current by the following formula:
wherein, IheatingHeating current for removing liquid and ice; i ismaxThe maximum heating current of the heating circuit is related to hardware parameters of the heating circuit, and is a fixed value for each designed heating circuit; i is0Heating current at zero flow at the present temperature, I0The relationship with temperature is prior art and will not be described in detail herein; mFIs the current measured flow; mRIs the flowmeter range. As can be seen from the above formula, the heating current for liquid and ice removal calculated in the present application varies with the measured flow rate. The higher the flow rate, the higher the heating current for de-icing and de-icing to ensure that liquid and/or ice from the probe is removed in the shortest possible time. That is, the heating current for removing liquid and ice provided by the invention canThe time efficiency and the energy efficiency of liquid removal and deicing are guaranteed to be higher.
The embodiment provides a device for removing liquid and ice on a probe in gas medium flow measurement, which can effectively remove liquid and/or ice on the surface of the probe in flow measurement. And a specific calculation method of the liquid removing and deicing heating current is also provided, so that the liquid removing and deicing heating process has higher time efficiency and energy efficiency.
Referring to fig. 5, fig. 5 is a block diagram of a probe liquid removing and deicing device in a gas medium flow measurement according to a fifth embodiment of the present invention. As shown in fig. 5, the present embodiment adds three functional modules on the basis of the fourth embodiment, namely, a mode switching module 5, a liquid-removing and deicing function setting module 6, and a liquid-removing and deicing function determining module 7, which are respectively connected to the control module 1. The functions and connection relationships of the other modules are the same as those of the fourth embodiment, and will not be described again. The three newly added function modules will be described in detail below.
The mode switching module 5 is used for sending a working mode switching signal to the control module 1, and the control module 1 controls the probe liquid and ice removing device to switch between a liquid and ice removing heating mode and a flow measurement mode in gas medium flow measurement according to the working mode switching signal. When the liquid and ice removing heating mode is switched to the flow measurement mode, the control module 1 controls the probe liquid and ice removing device to perform flow measurement after waiting for the preset heat balance time in the gas medium flow measurement.
And the liquid and ice removing function setting module 6 is used for setting whether to start the liquid and ice removing function. In this embodiment, a user can preset whether to start the liquid-removing and deicing function through the liquid-removing and deicing function setting module 6 according to actual conditions, can also start or close the liquid-removing and deicing function at any time in the measurement process, and can also adopt default settings of a system for direct measurement. Meanwhile, the flowmeter provided by the invention can memorize the system settings saved in the last shutdown, and defaults to adopt the system settings saved in the last shutdown in the next use, so that unnecessary manual operation is reduced, and the flowmeter is simple and convenient.
And the liquid and ice removing function judging module 7 is used for judging whether the liquid and ice removing function is started. If the liquid and ice removing functions are detected to be started, a signal is sent to the control module 1, and the control module 1 further triggers the liquid and ice removing heating current calculating module 3 to calculate liquid and ice removing heating current according to the current flow and temperature; if the liquid and ice removing functions are not started, the flow calculation module 4 directly outputs the current calculated flow as a final flow numerical value.
By implementing the embodiment, a diversified choice can be provided for a user, so that the liquid and ice removing function can be started by the user under the condition of requirement. Therefore, the gas flow can be directly measured by using the traditional method under the condition that the liquid and ice removing functions are not required to be started, the time and the energy are saved, and the cost is reduced. In addition, the mode switching module 5 can not only enable the device for removing liquid and deicing the probe in the gas medium flow measurement provided by the invention to have the function of removing liquid and deicing for the self-heating probe, but also have the function of continuously measuring flow after removing liquid and/or ice blocks for the self-heating probe, thereby providing a device for accurately measuring the flow of the liquid-containing gas medium, even the liquid-containing gas medium at low temperature.
In another preferred embodiment of the present invention, the control module 1 is further configured to control the self-heating probe to be heated by the de-icing and de-icing heating current at a predetermined cycle during the continuous measurement. In actual use, the measurement is often a continuous process. During the continuous measurement process, the self-heating probe may be stained with liquid drops or frozen again, and in order to realize accurate measurement, the process of calculating the liquid removing and deicing heating current, the liquid removing and deicing heating, waiting for heat balance and measuring the flow needs to be continuously and circularly executed. In such a cycle measurement process, the current flow of the measured gas is the initial flow in the next cycle, and is input into the deicing and fluid removal heating current calculation module 3 as a parameter for calculating the deicing and fluid removal heating current. The temperature probe 22 measures the temperature of the gas in real time all the time and sends the measured temperature to the control module 1 so that other modules can call the temperature parameter.
In the invention, the liquid removing, deicing and heating time, the waiting heat balance time and the liquid removing, deicing and heating interval time (which is approximately the time for continuously measuring the flow) can be preset according to the actual situation or can be adjusted at any time in the measuring process. In a preferred embodiment provided by the invention, the liquid removing and deicing heating period is 2min-64min, wherein the liquid removing and deicing heating duration range is 0-20 s, and the waiting heat balance time is 0-99 s.
By implementing the embodiment, the measurement accuracy can be continuously ensured in long-time continuous measurement, and the influence on the measurement accuracy due to the fact that the self-heating probe is again stained with liquid drops or frozen in the measurement process can be avoided.
The above description relates to various modules. These modules typically include hardware and/or a combination of hardware and software (e.g., firmware). The modules may also include computer-readable media (e.g., non-transitory media) containing instructions (e.g., software instructions) that, when executed by a processor, perform various functional features of the present invention. Accordingly, the scope of the invention is not limited by the specific hardware and/or software characteristics of the modules explicitly mentioned in the embodiments, unless explicitly claimed. As a non-limiting example, the present invention may in embodiments be implemented by one or more processors (e.g., microprocessors, digital signal processors, baseband processors, microcontrollers) executing software instructions (e.g., stored in volatile and/or persistent memory). In addition, the present invention may also be implemented in an Application Specific Integrated Circuit (ASIC) and/or other hardware components. It should be noted that the above description of the various modules is divided into these modules for clarity of illustration. However, in actual implementation, the boundaries of the various modules may be fuzzy. For example, any or all of the functional modules herein may share various hardware and/or software elements. Also for example, any and/or all of the functional modules herein may be implemented in whole or in part by a common processor executing software instructions. Additionally, various software sub-modules executed by one or more processors may be shared among the various software modules. Accordingly, the scope of the present invention is not limited by the mandatory boundaries between the various hardware and/or software elements, unless explicitly claimed otherwise.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (4)
1. A method for removing liquid and ice from a probe in gas medium flow measurement is used for a thermal gas mass flowmeter and is characterized by comprising the following steps:
s1, measuring the current temperature and flow of gas;
s2, calculating a liquid and ice removing heating current according to the measured temperature and flow;
s3, controlling a self-heating probe of the flowmeter to heat according to preset heating time and the liquid and ice removing heating current;
s4, switching to a normal measurement mode, and measuring the current flow after waiting for preset heat balance time;
in the continuous measurement process, the steps S2, S3 and S4 are executed in a loop;
the method further comprises the following steps after the step S1:
s5, judging whether the liquid removing and deicing functions of the probe are started or not, if so, turning to the step S2; otherwise, the step S1 is returned to.
2. The method for removing liquid and deicing fluid in a probe in gas medium flow measurement according to claim 1, wherein in said step S2, the heating current for removing liquid and deicing is calculated by the following formula:
wherein, IheatingHeating current for removing liquid and ice ImaxFor maximum heating current of the heating circuit, I0Heating current at zero flow at the present temperature, MFFor the currently measured flow, MRIs the flowmeter range.
3. A device for removing liquid and ice from a probe in gas medium flow measurement is used for a thermal gas mass flowmeter and comprises a flow calculation module, a control module and a sensor module, wherein the sensor module comprises a self-heating probe for heating and a temperature probe for measuring temperature; wherein,
the control module is respectively connected to the flow calculation module, the sensor module and the liquid and ice removal heating current calculation module;
the flow calculation module calculates the current flow according to the data measured by the sensor module, the liquid and ice removing heating current calculation module calculates the liquid and ice removing heating current according to the measured flow and the temperature measured by the temperature probe, and the control module controls the self-heating probe to heat according to the preset heating time and the liquid and ice removing heating current so as to remove liquid and/or ice blocks on the self-heating probe;
the device also comprises a mode switching module; the mode switching module is used for sending a working mode switching signal to the control module, and the control module controls the liquid and ice removing device in the gas medium flow measurement to switch between a liquid and ice removing heating mode and a flow measurement mode according to the working mode switching signal; when the liquid and ice removing heating mode is switched to the flow measurement mode, the control module controls the liquid and ice removing device in the gas medium flow measurement to wait for preset heat balance time and then carry out flow measurement;
the control module is also used for controlling the self-heating probe to circularly heat according to the liquid and ice removing heating current according to a preset period in the continuous measurement process;
the device also comprises a liquid and ice removing function setting module and a liquid and ice removing function judging module; wherein
The liquid and ice removing function setting module is used for setting whether to start a liquid and ice removing function;
and the liquid and ice removing function judging module is used for judging whether the liquid and ice removing function is started.
4. The device for removing liquid and ice from a probe in gas medium flow measurement according to claim 3, wherein the liquid and ice removing heating current calculating module calculates the liquid and ice removing heating current according to the following formula:
wherein, IheatingHeating current for removing liquid and ice ImaxFor maximum heating current of the heating circuit, I0For zero flow heating current at the present temperature, MFFor the currently measured flow, MRIs the flowmeter range.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1668243A (en) * | 2002-07-24 | 2005-09-14 | 弗萨米德医疗系统有限公司 | Respiratory flow sensor |
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| DE10111840C2 (en) * | 2001-03-13 | 2003-06-05 | Bosch Gmbh Robert | Process for avoiding contamination on a sensor chip and use of an additional heater on a sensor chip |
| DE10118781B4 (en) * | 2001-04-18 | 2005-04-21 | Robert Bosch Gmbh | Method for avoiding soiling on a sensor chip and use of a potential surface on a sensor chip |
| DE102005016449A1 (en) * | 2005-04-11 | 2006-10-12 | Robert Bosch Gmbh | Heated hot film air mass meter |
| CN2896230Y (en) * | 2005-12-06 | 2007-05-02 | 上海中油石油仪器制造有限公司 | Liquid metering device |
| CN201229187Y (en) * | 2008-07-22 | 2009-04-29 | 赵树行 | Tower-shaped flowmeter with heating function |
| CN104034378B (en) * | 2014-06-27 | 2017-02-15 | 天津大学 | Constant-current thermal gas mass flow meter and measuring method implemented by same |
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| CN1668243A (en) * | 2002-07-24 | 2005-09-14 | 弗萨米德医疗系统有限公司 | Respiratory flow sensor |
Non-Patent Citations (1)
| Title |
|---|
| Integrated smart gas flow sensor with 2.6mW total power consumption and 80dB dynamic range;Massimo Piotto, Francesco Del Cesta, Paolo Bruschi;《Microelectronic Engineering》;20160615;第159卷;159-163 |
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