A portable large cavity temperature and humidity generator and its use method

Abstract

The present invention discloses a portable large-cavity temperature and humidity generator and a method for using the same. The generator includes: a cavity, a drying unit, a humidifying unit, a temperature and humidity monitoring control unit, and a temperature and humidity sensor. The portable large-cavity temperature and humidity generator disclosed in the present invention can quickly dry wet air by dehumidifying the drying tank, and the drying tank can be reused multiple times, avoiding waste of desiccant and cumbersome replacement operations; the generator first extracts all the air in the cavity to directly return the initial relative humidity of the cavity to zero, and then quickly controls the humidity by calculating the humidification time. The temperature control adopts dual control measures of air circulation and annular water pipes, which is conducive to quickly controlling the temperature. The device proposed in the present invention greatly improves the time it takes for the portable large-cavity temperature and humidity generator to reach stability, and greatly improves the technical means of measuring the temperature and humidity meter on site.

Description

Technical Field

[0001] The invention belongs to the field of measuring systems for measuring physical quantities, and in particular relates to a portable large-cavity temperature and humidity generator and a use method thereof. Background Art

[0002] According to JJF (Military Industry) 165-2017 "Digital Thermohygrometer Calibration Specifications" and other regulations, various thermohygrometers need to be calibrated regularly, so a stable and controllable temperature and humidity calibration environment is required. The temperature and humidity generator is the main equipment for the laboratory to conduct metrological calibration of thermohygrometers.

[0003] At present, the technology of standard temperature and humidity generators for laboratories at home and abroad has become mature. The temperature and humidity standard boxes used in laboratories of various metrological institutions mainly produce constant and uniform temperature and humidity fields through dual-temperature method and temperature and humidity control method. In recent years, the demand for on-site portable temperature and humidity generators has also increased rapidly. Domestic researchers have developed a variety of portable temperature and humidity control boxes using different principles and methods, such as independent temperature and humidity control and water circulation, efficient gas-liquid heat exchange, and multi-cavity infiltration of electromagnetic valve three-way gas distribution system. However, the test chamber of the above-mentioned temperature and humidity generator is small and cannot meet actual needs. Therefore, it is necessary to develop a portable temperature generator with a large cavity. Summary of the invention

[0004] In view of this, the portable large-cavity temperature and humidity generator disclosed in the present invention can quickly dry wet air by dehumidifying a drying tank before use, and the drying tank can be reused many times, avoiding the waste of desiccant and the tedious operation of replacement; the generator first extracts all the air in the cavity to directly return the initial relative humidity of the cavity to zero, and then quickly realizes humidity control by calculating the humidification time, and the temperature control adopts dual control measures of air circulation and annular water pipe, which is conducive to quickly realizing temperature control.

[0005] To achieve this object, the first aspect of the present invention protects a portable large cavity temperature and humidity generator, the generator comprising: a cavity, a drying unit, a humidifying unit, a temperature and humidity monitoring control unit and a temperature and humidity sensor;

[0006] The cavity comprises a test chamber and a circulation chamber therein, wherein the test chamber and the cavity share a top panel, and spaces are left between the side and bottom panels of the test chamber and the side and bottom panels of the cavity respectively, and the space between the test chamber and the cavity constitutes the circulation chamber; the test chamber and the circulation chamber are in communication;

[0007] The drying unit and the humidifying unit are both installed in the circulation chamber, wherein the drying unit connects the test chamber, the outside of the cavity and the circulation chamber through an air pipeline and a valve; the humidifying unit includes: a convection component, a heating component and a moisture generating component, wherein the convection component is installed at the opening position of the bottom panel of the test chamber, the heating component is rotated at the bottom of the convection component, and the moisture generating component is installed in the circulation chamber, and the moisture generated by the convection component acts vertically on the convection component;

[0008] The temperature and humidity monitoring control unit is installed on the cavity panel, and the temperature and humidity sensor is installed inside the test chamber.

[0009] Preferably, the cavity is divided into two layers, the inner layer is an epoxy resin layer, and the outer layer is an insulating foam material layer. A transparent observation hole is provided on the part shared by the top panel of the cavity and the test chamber; a first fan is installed on the part shared by the top panel of the cavity and the circulation chamber, and the wind direction of the first fan is inward and perpendicular to the circulation chamber.

[0010] Preferably, through holes are arranged on the side panels of the test chamber, sample placement columns arranged in an array are evenly arranged on the bottom panel, and a hole is opened in the middle of the bottom panel.

[0011] Preferably, the drying unit comprises: a drying tank, a gas pipeline, a multi-way solenoid valve, a first motor and a two-way solenoid valve;

[0012] The drying tank is connected to the first interface of the multi-way solenoid valve and the first interface of the two-way solenoid valve through gas pipelines respectively;

[0013] The second interface of the multi-way solenoid valve is connected to the first motor through a gas pipeline, and the third interface is directly connected to the gas pipeline, and the gas pipeline is extended to the outside of the cavity;

[0014] The first motor is connected to the test chamber via a gas pipeline, and the gas pipeline extends into the test chamber;

[0015] The two-way solenoid valve has a built-in temperature and humidity sensor, and the second interface of the two-way solenoid valve extends into the circulation chamber through an air pipeline.

[0016] Preferably, the drying tank is of a U-shaped structure, with a U-shaped shell on the outside, and metal mesh partitions are installed at both ends of the U-shaped shell, and the metal mesh partition divides the inside of the U-shaped shell into a first chamber and a third chamber located at both ends and a second chamber located between the first chamber and the third chamber; the first chamber and the third chamber are successively provided with a solenoid valve, a gas flow sensor, a humidity sensor and a second fan, wherein the solenoid valve is installed at the air inlet and the air outlet of the first chamber and the third chamber, the gas flow sensor and the humidity sensor are both installed on the pipe connected to the solenoid valve inside the shell, and the second fan is installed between the gas flow sensor and the metal mesh partition; the second chamber is a U-shaped drying chamber, which includes: a spiral heating wire fixedly arranged along the central axis of the second chamber, a desiccant silica gel filled between the heating wire and the second chamber shell, and a temperature sensor located in the middle of the second chamber.

[0017] Preferably, the convection component includes: a flow fan installed at the opening position at the bottom of the test chamber and a corrugated fin installed below the flow fan, and the wind direction of the flow fan is toward the inside of the test chamber; the heating component is a first heating and cooling plate installed below the corrugated fin, and the bottom of the first cooling plate is directly exposed to the air outside the cavity; the moisture generating component includes: a water adding tank installed in the circulation chamber, a second motor connected to the water adding tank, a water valve connected to the second motor, and an ultrasonic humidifier connected to the water valve, and the water vapor nozzle of the ultrasonic humidifier is vertically opposite to the corrugated fin.

[0018] Preferably, a second heating and cooling plate is arranged at the bottom of the water adding pool, and a temperature sensor is installed inside. The second heating and cooling plate is closely attached to the base of the water adding pool and its bottom is directly exposed to the air outside the cavity; the water adding pool is also connected to a third motor, and the third motor is connected to a water pipe. The water pipe is laid in a ring on the inner surface of the bottom of the test chamber, and a metal heat transfer plate is installed on the surface of the water pipe.

[0019] Preferably, the temperature and humidity sensor is installed in the middle of the four side edges inside the test chamber.

[0020] The second aspect of the present invention protects a method for using the portable large cavity temperature and humidity generator as described above, the method comprising:

[0021] S1: Turn on the fan to dehumidify the drying tank;

[0022] S2: Control the multi-way solenoid valve and start the first motor to make the gas flow from the cavity to the outside of the cavity. After the gas in the cavity is exhausted, the internal volume V of the cavity is calculated by using the equal volume substitution method;

[0023] S3: Set the temperature T and relative humidity RH that the test chamber needs to reach on the temperature and humidity monitoring control unit;

[0024] S4: Control the multi-way solenoid valve to allow the gas to flow from the outside of the chamber through the drying tank to the circulation chamber, so that the air in the test chamber is completely dry and in a normal air pressure state;

[0025] S5: The temperature and humidity monitoring control unit controls the moisture generating component to humidify and adjust the test chamber;

[0026] S6: The temperature and humidity monitoring control unit determines and adjusts the temperature in the test room in real time;

[0027] S7: The temperature and humidity monitoring control unit monitors the temperature and relative humidity of the test room in real time and regulates and maintains them.

[0028] Preferably, in S1, the process of dehumidifying the drying tank is as follows:

[0029] The first motor is turned on to control the multi-way solenoid valve and the two-way solenoid valve, so that the gas flows from the test chamber to the circulation chamber after passing through the drying tank; at the same time, the humidity sensors in the first chamber and the third chamber inside the drying tank are used to monitor the air humidity in the drying tank in real time. When the relative humidity change of the humidity sensors in the first chamber and the third chamber is less than 5%, the multi-way solenoid valve and the two-way solenoid valve are closed, and then the first heating and cooling sheet is closed, and the dehumidification process ends;

[0030] Preferably, the humidification adjustment process in S5 is:

[0031] First, calculate the water valve opening time t according to the set relative humidity RH on , t on The calculation formula is:

[0032]

[0033] Where: P T It represents the saturated vapor pressure of water at temperature T. The specific value can be obtained by looking up the saturated vapor pressure table of water in MPa. V represents the internal volume of the cavity in m 3 ; RH represents the set relative humidity, in %; R represents the universal gas constant, in MPa·m 3 / (kmol·K); T represents the set temperature, the unit is K; ρ T Indicates the density of water at temperature T, in kg / m 3 , this value can be obtained by looking up the water density table;

[0034] Next, turn on the second motor and high-frequency ultrasonic humidifier, and then open the water valve. on Close after time;

[0035] Preferably, the method for real-time determination and adjustment of the temperature in the test chamber in S6 is as follows: if the temperature T set in S3 is greater than the initial temperature T0 of the temperature and humidity sensor, a heating operation is performed; otherwise, a cooling operation is performed;

[0036] The temperature rising operation is as follows: starting the third motor, starting and setting the top of the first temperature rising and cooling plate and the top of the second temperature rising and cooling plate to a temperature rising state, assuming that the temperature rising time is t1, setting the top temperature of the first temperature rising and cooling plate and the top of the second temperature rising and cooling plate to (T0+80)°C before time t1, and then linearly decreasing to T and then maintaining at T, wherein the temperature rising time t1 depends on the difference between the set temperature T and the initial temperature T0 of the temperature and humidity sensor, and the linear decreasing time is 1 / 4 of t1;

[0037] The cooling operation is: start the third motor, start and set the top of the first heating and cooling plate and the second heating and cooling plate to a cooling state, assuming that the cooling time is t2, set the top temperature of the first heating and cooling plate and the second heating and cooling plate to (T0-70)°C before time t2, and then linearly rise to temperature T and maintain it at T, wherein the cooling time t2 depends on the difference between the set temperature T and the initial temperature T0 of the temperature and humidity sensor, and the linear rise time is 1 / 3 of t2.

[0038] The beneficial effects of the present invention are as follows: the portable large-cavity temperature and humidity generator disclosed in the present invention can quickly dry wet air by dehumidifying the drying tank, and the drying tank can be reused many times, avoiding waste of desiccant and cumbersome operation of replacement; the generator of the present application first extracts all the air in the cavity to directly return the initial relative humidity of the cavity to zero, and then quickly realizes humidity control by calculating the humidification time, and the temperature control adopts dual control measures of air circulation and annular water pipe, which is conducive to quickly realizing temperature control. The device proposed by the present invention greatly improves the time for the portable large-cavity temperature and humidity generator to reach stability, and greatly improves the technical means of measuring temperature and humidity meters on site. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a schematic diagram of the structure of a portable large-cavity temperature and humidity generator according to an embodiment of the present application;

[0040] Figure 2 This is a schematic diagram of the structure of the drying tank in the embodiment of the present application;

[0041] In the figure: 1. Cavity 2. Circulation chamber 3. Test chamber 4. Side panel 5. Temperature and humidity sensor 6. Flow fan 7. Sample placement column 8. Water pipe 9. First motor 10. Multi-way solenoid valve 11. Drying tank 12. Two-way solenoid valve 13. First heating and cooling plate 14. Corrugated fin 15. Ultrasonic humidifier 16. Second motor 17. Water adding tank 18. Second heating and cooling plate 19. Water valve 20. Third motor 21. Temperature and humidity monitoring control unit 22. First fan 23. Transparent observation hole 111. Solenoid valve 112. U-shaped shell 113. Heating wire 114. Desiccant silica gel 115. Temperature sensor 116. Drying chamber 117. Second fan 118. Gas flow sensor 119. Humidity sensor. DETAILED DESCRIPTION

[0042] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

[0043] The portable large-cavity temperature and humidity generator disclosed in the present invention can quickly dry wet air by dehumidifying the drying tank, and the drying tank can be reused many times, avoiding the waste of desiccant and the cumbersome operation of replacement; the generator of the present application first extracts all the air in the cavity to directly return the initial relative humidity of the cavity to zero, and then quickly realizes humidity control by calculating the humidification time, and the temperature control adopts the dual control measures of air circulation and annular water pipe, which is conducive to quickly realizing temperature control. The device proposed by the present invention greatly improves the time for the portable large-cavity temperature and humidity generator to reach stability, and greatly improves the technical means of measuring the temperature and humidity meter on site.

[0044] The following is combined with Figures 1-2 And the specific embodiment describes in detail the optimization method of the portable large cavity humidity generator of the present invention.

[0045] Example

[0046] like Figure 1 The portable large cavity temperature and humidity generator shown includes: a cavity 1, a drying unit, a humidifying unit, a temperature and humidity monitoring control unit 21 and a temperature and humidity sensor 5. In order to clearly understand the present application, each component is introduced separately below:

[0047] (1) The cavity 1 includes a test chamber 3 and a circulation chamber 2 located therein. The test chamber 3 and the cavity 1 share a top panel. The side panels 4 and the bottom panel of the test chamber 3 are respectively spaced a certain distance from the side panels and the bottom panel of the cavity 1. As a method of realizing the large cavity feature of the temperature and humidity generator to the maximum extent in the present application, the distance between the left and right panels of the test chamber 3 and the inner panel of the cavity 1 is set to 40 mm, and the distance between the bottom panel of the test chamber 3 and the inner side of the bottom of the cavity 1 is set to 80 mm. The space between the test chamber 3 and the inner surface of the cavity 1 constitutes the circulation chamber 2;

[0048] As an embodiment, the cavity 1 is divided into two layers, the inner layer is an epoxy resin layer, and the outer layer is an insulating foam material layer. The two-layer design can better achieve the effect of heat preservation and moisture retention; the part of the top panel of the cavity 1 shared with the test chamber 3 is provided with a transparent observation hole 23, which is convenient for real-time monitoring of the situation in the test chamber 3; the part of the top panel of the cavity 1 shared with the circulation chamber 2 is installed with a first fan 22, and the wind of the first fan 22 is inward and perpendicular to the circulation chamber 2, so as to accelerate the air flow in the cavity 1.

[0049] As an embodiment, the panel of the test chamber 3 is made of epoxy resin material. In order to maintain air flow between the test chamber 3 and the circulation chamber 2, a plurality of through holes are arranged on the side panel 4. An array of epoxy resin cylindrical sample placement columns 7 are evenly arranged on the bottom panel to facilitate the placement of samples to be tested. In order to accelerate air circulation from the bottom of the test chamber 3, a circular hole for installing a convection unit is opened in the middle of the bottom.

[0050] (2) The drying unit is installed in the circulation chamber 2. The drying unit connects the test chamber 3, the outside of the cavity 1 and the circulation chamber 2 through the gas pipeline and the valve. Figure 1 As shown, the drying unit includes: a drying tank 11, a gas pipeline, a multi-way solenoid valve 10, a first motor 9 and a two-way solenoid valve 12. The drying tank 11 is connected to the first interface of the multi-way solenoid valve 10 and the first interface of the two-way solenoid valve 12 through the gas pipeline respectively; the second interface of the multi-way solenoid valve 10 is connected to the first motor 9 through the gas pipeline, and the third interface is directly connected to the gas pipeline, and the gas pipeline is extended to the outside of the cavity 1; the first motor 9 is connected to the test chamber 3 through the gas pipeline, and the gas pipeline extends into the test chamber 3; the two-way solenoid valve 12 has a built-in temperature and humidity sensor, and the second interface of the two-way solenoid valve 12 is extended into the circulation chamber 2 through the gas pipeline.

[0051] Through the connection of the above-mentioned gas pipelines, the multi-way controlled solenoid valve 10 can realize multi-directional flow of the gas path inside the cavity 1, including: gas flows from the test chamber 3 to the outside of the cavity 1, from the test chamber 3 to the circulation chamber 2, and from the outside of the cavity 1 to the circulation chamber 2.

[0052] like Figure 2As shown, as the best embodiment, the drying tank 11 is in a U-shaped structure, and its outer side is a U-shaped shell 112, and the U-shaped shell 112 is made of a transparent acrylic material that is heat-resistant to 200°C. Metal grid partitions are installed at both ends of the U-shaped shell 112, and the metal grid partition divides the interior of the U-shaped shell 112 into a first chamber and a third chamber located at both ends, and a second chamber located between the first chamber and the third chamber; the first chamber and the third chamber are respectively provided with a solenoid valve 111, a gas flow sensor 118, a humidity sensor 119 and a second fan 117, wherein the solenoid valve 111 is installed at the air inlet and the air outlet of the first chamber and the third chamber to control the flow of gas, and the gas flow sensor 118 and the humidity sensor 119 are It is installed on the pipeline connected to the solenoid valve inside the shell, and is used to detect the gas flow and the relative humidity of the gas passing through the drying tank. The second fan 117 is installed between the gas flow sensor 118 and the metal grid partition, and is used to take away the volatilized moisture in the desiccant in time during the dehumidification process of the drying tank; the second chamber is a U-shaped drying chamber 116, which includes: a spiral heating wire 113 fixedly arranged along the central axis of the second chamber, a desiccant silica gel 114 filled between the heating wire 113 and the second chamber shell, and a temperature sensor 115 located in the middle of the second chamber.

[0053] (3) The humidification unit is also installed in the circulation chamber 3, and the humidification unit includes: a convection component, a heating component and a moisture generating component.

[0054] As an embodiment, the convection assembly includes a flow fan 6 installed at the opening position at the bottom of the test chamber 3 and a corrugated fin 14 installed below the flow fan. The wind direction of the flow fan 6 is toward the inside of the test chamber 3, and its purpose is to accelerate the air flow in the cavity and quickly send the water vapor generated by the moisture generating assembly into the test chamber 3, so that the test chamber 3 quickly and evenly reaches the humidity required for detection; the corrugated fin 14 is a copper material with a wavy structure, and this structural design can prevent the mist from condensing directly;

[0055] As an embodiment, the heating component is a first heating and cooling plate 13 installed under the corrugated fins. The bottom of the first cooling plate 13 is directly exposed to the air outside the cavity. It is used to heat the corrugated fins 14 and further heat the water vapor through the corrugated fins 14. Those skilled in the art should understand that other components with heating and cooling control are equivalent substitutes for the first heating and cooling plate 13.

[0056] The moisture generating assembly includes: a water adding tank 17 installed in the circulation chamber, a second motor 16 connected to the water adding tank 17, a water valve 19 connected to the second motor 16, and an ultrasonic humidifier 15 connected to the water valve 19, wherein the water vapor nozzle of the ultrasonic humidifier 15 is vertically opposite to the corrugated fin 14, and the corrugated fin 14 transports the water vapor to the test wet 3 in time through the flow fan 6.

[0057] As an embodiment, a second heating and cooling sheet 18 is provided at the bottom of the water adding pool 17, and a temperature sensor is installed inside. The second heating and cooling sheet 18 is close to the base of the water adding pool 17 and its bottom is directly exposed to the air outside the cavity 1. The second heating and cooling sheet 18 can regulate the temperature of the water in the water adding pool 17;

[0058] As the best embodiment, the present application further connects a third motor 20 to the water adding tank 17, and the third motor 20 is connected to the water pipe 8. The water pipe 8 is laid in a ring on the inner surface of the bottom surface of the test chamber 3. The setting of the water pipe 8 further increases the temperature rising element in the test chamber 3. The hot water circulation in the circularly arranged water pipe 8 and the water vapor with a certain temperature blown in by the flow fan 6 can evenly achieve the temperature rising or cooling in the test chamber 3. More preferably, a metal heat transfer plate is installed on the surface of the water pipe 8 to accelerate its temperature rising effect.

[0059] The first temperature rising and cooling plate 13 and the second temperature rising and cooling plate 18 are stacked semiconductor temperature control elements. When current passes through them in the forward direction, the temperature of the upper part rises, and when current passes through them in the reverse direction, the temperature of the upper part drops.

[0060] (4) The temperature and humidity monitoring control unit 21 is installed on the cavity panel, and is connected to the temperature and humidity sensor 5, the first motor 9, the multi-way solenoid valve 10, the drying tank 11, the two-way solenoid valve 12, the first temperature rising and cooling plate 13, the air blower 6, the ultrasonic humidifier 15, the second motor 16, the water tank 17, the water valve 19, the third motor 20, and the first fan 22 in the test chamber 3 through aviation plugs. The temperature and humidity monitoring control unit (21) also provides power to the above-mentioned components and controls the working status.

[0061] (5) The temperature and humidity sensor is installed inside the test chamber and in the middle of the four side edges inside the test chamber.

[0062] The method of using the portable large cavity temperature and humidity generator described above is as follows:

[0063] S1: Turn on the fan to dehumidify the drying tank;

[0064] The dehumidification process is as follows: the first motor is turned on to control the multi-way solenoid valve and the two-way solenoid valve so that the gas flows from the test chamber to the circulation chamber after passing through the drying tank; at the same time, the humidity sensors in the first chamber and the third chamber inside the drying tank are used to monitor the air humidity in the drying tank in real time. When the relative humidity change of the humidity sensors in the first chamber and the third chamber is less than 5%, the multi-way solenoid valve and the two-way solenoid valve are closed, and then the first heating and cooling sheet is closed, and the dehumidification process ends;

[0065] S2: Control the multi-way solenoid valve and start the first motor to make the gas flow from the cavity to the outside of the cavity. After the gas in the cavity is exhausted, the internal volume V of the cavity is calculated by using the equal volume substitution method;

[0066] S3: Set the temperature T and relative humidity RH that the test chamber needs to reach on the temperature and humidity monitoring control unit;

[0067] S4: Control the multi-way solenoid valve to allow the gas to flow from the outside of the chamber through the drying tank to the circulation chamber, so that the air in the test chamber is completely dry and in a normal air pressure state;

[0068] S5: The temperature and humidity monitoring control unit controls the moisture generating component to humidify and adjust the test chamber;

[0069] The humidification adjustment process is as follows: First, the water valve opening time t is calculated according to the set relative humidity RH on , t on The calculation formula is:

[0070]

[0071] Where: P T It represents the saturated vapor pressure of water at temperature T. The specific value can be obtained by looking up the saturated vapor pressure table of water in MPa. V represents the internal volume of the cavity in m 3 ; RH represents the set relative humidity, in %; R represents the universal gas constant, in MPa·m 3 / (kmol·K); T represents the set temperature, the unit is K; ρ T Indicates the density of water at temperature T, in kg / m 3 , which can be obtained by looking up the water density table; then, turn on the second motor and the high-frequency ultrasonic humidifier, and then open the water valve t on Close after time;

[0072] S6: The temperature and humidity monitoring control unit determines and adjusts the temperature in the test room in real time; the real-time determination and adjustment method is as follows: if the temperature T set in S3 is greater than the initial temperature T0 of the temperature and humidity sensor, the temperature is increased, otherwise, the temperature is decreased;

[0073] The heating operation is as follows: start the third motor, start and set the top of the first heating and cooling plate and the top of the second heating and cooling plate to a heating state, assuming that the heating time is t1, set the top temperature of the first heating and cooling plate and the top of the second heating and cooling plate to (T0+80)°C before t1, then linearly decrease to T and then maintain at T, wherein the heating time t1 depends on the difference between the set temperature T and the initial temperature T0 of the temperature and humidity sensor, and the linear decrease time is 1 / 4 of t1;

[0074] The cooling operation is as follows: start the third motor, start and set the top of the first heating and cooling plate and the second heating and cooling plate to a cooling state, assuming that the cooling time is t2, set the top temperature of the first heating and cooling plate and the second heating and cooling plate to (T0-70)°C before time t2, and then linearly rise to temperature T and maintain at T, wherein the cooling time t2 depends on the difference between the set temperature T and the initial temperature T0 of the temperature and humidity sensor, and the linear rise time is 1 / 3 of t2.

[0075] S7: The temperature and humidity monitoring control unit monitors the temperature and relative humidity of the test room in real time and regulates and maintains them.

Claims

1. A method for using a portable large-cavity temperature and humidity generator, the generator comprising: Cavity, drying unit, humidifying unit, temperature and humidity monitoring control unit and temperature and humidity sensor; The cavity comprises a test chamber and a circulation chamber therein, wherein the test chamber and the cavity share a top panel, and spaces are left between the side and bottom panels of the test chamber and the side and bottom panels of the cavity respectively, and the space between the test chamber and the cavity constitutes a circulation chamber; the test chamber is connected to the circulation chamber; the drying unit and the humidifying unit are both installed in the circulation chamber, wherein the drying unit is connected to the test chamber, the outside of the cavity and the circulation chamber through an air pipeline and a valve; the humidifying unit comprises: a convection component, a heating component and a moisture generating component, wherein the convection component is installed at the opening position of the bottom panel of the test chamber, the heating component is rotated at the bottom of the convection component, the moisture generating component is installed in the circulation chamber, and the moisture generated by it acts vertically on the convection component; the temperature and humidity monitoring control unit is installed on the cavity panel, and the temperature and humidity sensor is installed inside the test chamber; the method comprises: S1: Turn on the air blower to dehumidify the drying tank in the drying unit; S2: Control the multi-way solenoid valve and start the first motor to make the gas flow from the cavity to the outside of the cavity. After the gas in the cavity is exhausted, the internal volume of the cavity is calculated using the equal volume substitution method. V ; S3: Set the temperature that the test chamber needs to reach on the temperature and humidity monitoring control unit T and relative humidity RH ; S4: Control the multi-way solenoid valve to allow the gas to flow from the outside of the chamber through the drying tank to the circulation chamber, so that the air in the test chamber is completely dry and in a normal air pressure state; S5: The temperature and humidity monitoring control unit controls the moisture generating component to humidify the test chamber. The humidification adjustment process is as follows: First, according to the relative humidity setting RH Calculate the opening time of the water valve t on , t on The calculation formula is: Where: P T Indicates temperature T The water saturated vapor pressure under the condition can be obtained by looking up the water saturated vapor pressure table. The unit is MPa ; V Represents the internal volume of the cavity, in units of m 3 ; RH Indicates the set relative humidity, in %; R represents the universal gas constant in MPa·m 3 / (kmol·K) ; T Indicates the set temperature in units of K ; ρ T Indicates temperature T The density of the water in kg / m 3 , this value can be obtained by looking up the water density table; Then turn on the second motor and high-frequency ultrasonic humidifier, and then open the water valve t on Close after time; S6: The temperature and humidity monitoring control unit determines and adjusts the temperature in the test room in real time; S7: The temperature and humidity monitoring control unit monitors the temperature and relative humidity of the test room in real time and regulates and maintains them.

2. The method for using the portable large cavity temperature and humidity generator according to claim 1, characterized in that: The cavity is divided into two layers, the inner layer is an epoxy resin layer, and the outer layer is an insulating foam material layer. A transparent observation hole is set on the part shared by the cavity top panel and the test chamber; a first fan is installed on the part shared by the cavity top panel and the circulation chamber, and the wind direction of the first fan is inward and perpendicular to the circulation chamber.

3. The method for using the portable large cavity temperature and humidity generator according to claim 1, characterized in that: The side panels of the test chamber are provided with through holes, the bottom panel is evenly provided with array-arranged sample placement columns, and the middle of the bottom panel is opened.

4. The method for using the portable large cavity temperature and humidity generator according to claim 1, characterized in that: The drying unit comprises: a drying tank, a gas pipeline, a multi-way solenoid valve, a first motor and a two-way solenoid valve; The drying tank is connected to the first interface of the multi-way solenoid valve and the first interface of the two-way solenoid valve through gas pipelines respectively; The second interface of the multi-way solenoid valve is connected to the first motor through a gas pipeline, and the third interface is directly connected to the gas pipeline, and the gas pipeline is extended to the outside of the cavity; The first motor is connected to the test chamber via a gas pipeline, and the gas pipeline extends into the test chamber; The two-way solenoid valve has a built-in temperature and humidity sensor, and the second interface of the two-way solenoid valve extends into the circulation chamber through an air pipeline.

5. The method for using the portable large cavity temperature and humidity generator according to claim 4, characterized in that: The drying tank is in a U-shaped structure, with a U-shaped shell on the outside. Metal mesh partitions are installed at both ends of the U-shaped shell, and the metal mesh partition divides the inside of the U-shaped shell into a first chamber and a third chamber located at both ends and a second chamber located between the first chamber and the third chamber; solenoid valves, gas flow sensors, humidity sensors and second fans are sequentially arranged inside the first chamber and the third chamber, wherein the solenoid valves are installed at the air inlet and the air outlet of the first chamber and the third chamber, the gas flow sensor and the humidity sensor are both installed on the pipe connected to the solenoid valve inside the shell, and the second fan is installed between the gas flow sensor and the metal mesh partition; the second chamber is a U-shaped drying chamber, which includes: a spiral heating wire fixedly arranged along the central axis of the second chamber, a desiccant silica gel filled between the heating wire and the shell of the second chamber, and a temperature sensor located in the middle of the second chamber.

6. The method for using the portable large cavity temperature and humidity generator according to claim 1, characterized in that: The convection component includes: a flow fan installed at the opening position at the bottom of the test chamber and a corrugated fin installed below the flow fan, and the wind direction of the flow fan is inside the test chamber; the heating component is a first heating and cooling plate installed below the corrugated fin, and the bottom of the first cooling plate is directly exposed to the air outside the cavity; the moisture generating component includes: a water adding tank installed in the circulation chamber, a second motor connected to the water adding tank, a water valve connected to the second motor, and an ultrasonic humidifier connected to the water valve, and the water vapor nozzle of the ultrasonic humidifier is vertically opposite to the corrugated fin.

7. The method for using the portable large cavity temperature and humidity generator according to claim 6, characterized in that: A second heating and cooling sheet is arranged at the bottom of the water adding pool, a temperature sensor is installed inside the water adding pool, the second heating and cooling sheet is closely attached to the base of the water adding pool and its bottom is directly exposed to the air outside the cavity; the water adding pool is also connected to a third motor, the third motor is connected to a water pipe, the water pipe is laid in a ring on the inner surface of the bottom of the test chamber, and a metal heat transfer sheet is installed on the surface of the water pipe.

8. The method for using the portable large cavity temperature and humidity generator according to claim 1, characterized in that: The temperature and humidity sensors are installed in the middle of the four side edges inside the test chamber.

9. The method for using the portable large cavity temperature and humidity generator according to any one of claims 1 to 8, characterized in that: In S1, the process of dehumidifying the drying tank is as follows: The first motor is turned on to control the multi-way solenoid valve and the two-way solenoid valve, so that the gas flows from the test chamber to the circulation chamber after passing through the drying tank; at the same time, the humidity sensors in the first chamber and the third chamber inside the drying tank are used to monitor the air humidity in the drying tank in real time. When the relative humidity change of the humidity sensors in the first chamber and the third chamber is less than 5%, the multi-way solenoid valve and the two-way solenoid valve are closed, and then the first heating and cooling sheet is closed, and the dehumidification process ends; The method for real-time determination and adjustment of the temperature in the test chamber in S6 is as follows: if the temperature set in S3 T If it is greater than the initial temperature T0 of the temperature and humidity sensor, the temperature is raised, otherwise, the temperature is lowered. The temperature rise operation is as follows: start the third motor, start and set the top of the first temperature rise and cooling plate and the top of the second temperature rise and cooling plate to a temperature rise state, assuming that the temperature rise time is t1, set the top temperature of the first temperature rise and cooling plate and the top of the second temperature rise and cooling plate to (T0+80)°C before t1, and then linearly decrease to T After that, it has remained T , where the heating time t1 depends on the set temperature T The difference between the initial temperature T0 of the temperature and humidity sensor, the linear decline time is 1 / 4 of t1; The cooling operation is as follows: start the third motor, start and set the top of the first heating and cooling plate and the second heating and cooling plate to a cooling state, assuming that the cooling time is t2, set the top temperature of the first heating and cooling plate and the second heating and cooling plate to (T0-70)°C before t2, and then linearly increase to the temperature T After that, it has remained T , where the cooling time t2 depends on the difference between the set temperature T and the initial temperature T0 of the temperature and humidity sensor, and the linear rise time is 1 / 3 of t2.

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