In-service air conditioner performance detection device and method

Abstract

The invention discloses an in-service air conditioner performance detection device and method. The device is composed of an air receiving chamber, an air exhaust chamber, an air return chamber, a differential pressure gauge, two mixers, a heating wire, a humidifier, an air return temperature and humidity probe and an air return motor. According to the device, the refrigerating capacity of the air conditioner is balanced through the heating amount of the heating wire, air blown out of the air conditioner is adjusted to be in the temperature and humidity state needed by detection through a heating and humidifying method, the device is connected to an air return opening of the air conditioner, circulating operation is conducted to reach the stable state, and continuous condensate water is generated; and the condensate water amount generated by the air conditioner within one hour is synchronously collected, the performance of the in-service air conditioner can be calculated according to the collected data, the air conditioner does not need to be disassembled and assembled, and damage to the in-service air conditioner is avoided.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of air conditioner performance detection, and in particular to a device and method for detecting the performance of an in-service air conditioner. Background Art

[0002] Old air conditioners often experience a significant drop in performance due to dirt, blockage and aging. At this time, the air conditioner needs to be tested for performance to determine whether its various performance indicators meet the standards for replacing the air conditioner.

[0003] However, the traditional method of inspecting old air conditioners is to dismantle them and send them to the laboratory for inspection. This inspection method is time-consuming and labor-intensive and requires repeated disassembly and assembly, which can easily cause secondary damage to the air conditioner.

[0004] Therefore, there is an urgent need for a method that can accurately evaluate the performance level of the air conditioner in use without dismantling the old air conditioner, so as to provide strong support for whether the air conditioner should be replaced. Summary of the Invention

[0005] The present invention provides a device and method for detecting the performance of an in-service air conditioner, so as to realize detecting the air conditioner by adopting a scientific method without damaging the product.

[0006] In a first aspect, an embodiment of the present invention provides a device for detecting the performance of an in-service air conditioner, comprising: A wind receiving chamber, a differential pressure gauge, and an air inlet port provided on one side of the wind receiving chamber; An exhaust chamber, and a plurality of groups of heating wires and a humidifier arranged in the exhaust chamber; a return air chamber, a return air temperature and humidity probe disposed in the return air chamber, a return air port disposed on one side of the return air chamber, and a return air motor disposed at the return air port; the return air temperature and humidity probe being used to detect the dry-bulb temperature and wet-bulb temperature of the return air; a first PID controller, a second PID controller, and a third PID controller; The first PID controller is connected to the differential pressure gauge and is used to control the static pressure of the air outlet by adjusting the air volume of the return air motor; The air inlet port is used to connect to the air outlet of the air conditioner, and the air return port is used to connect to the air return outlet of the air conditioner; The second PID controller is connected to the return air dry bulb temperature probe and is used to adjust the heating value of the multiple sets of heating wires to control the return air dry bulb temperature; The third PID controller is connected to the return air wet-bulb temperature probe and is used to adjust the humidification amount of the humidifier to control the return air wet-bulb temperature.

[0007] Optionally, a plurality of air pressure measuring points and static pressure pipes are provided around the wind receiving chamber, and the wind receiving chamber is connected to the differential pressure gauge through the static pressure pipe.

[0008] Optionally, the device further includes: a mixer provided in the wind receiving chamber, for mixing the air outlet temperature of the air conditioner.

[0009] Optionally, the device further comprises: a mixer arranged in the return air chamber, for mixing the required return air temperature and humidity.

[0010] In a second aspect, an embodiment of the present invention further provides a method for detecting the performance of an in-service air conditioner, which is implemented using the in-service air conditioner performance detection device described in any of the above embodiments, comprising: Connect the in-service air conditioner performance test device to the air inlet and return air ports of the air conditioner being tested and take insulation measures; Set the outlet static pressure, return air dry-bulb temperature and return air wet-bulb temperature to the preset working conditions and power on; Run the air conditioner under test. When the air conditioner reaches a stable state and condensation water is continuously generated, measure the power consumption of multiple sets of heating wires for 1 hour. E , Condensation water volume of air conditioner in 1 hour G and the outdoor unit return air outlet dry bulb temperature T; According to the power consumption of the multiple groups of heating wires for 1 hour E , the amount of condensed water produced by the air conditioner in 1 hour G And the dry bulb temperature T of the outdoor unit return air outlet is used to calculate the cooling capacity of the air conditioner at the condensing temperature T.

[0011] Optionally, the preset working condition is: setting the outlet static pressure to 0Pa, the return air dry-bulb temperature to 27°C and the return air wet-bulb temperature to 19°C.

[0012] Optionally, the cooling capacity of the air conditioner at T condensing temperature is:

[0013] in, E The power consumption of multiple sets of heating wires for 1 hour; G is the amount of condensed water produced by the air conditioner in 1 hour; k is the latent heat of vaporization of water, k=(2501-2.38t1)×10 3 J / kg , t1 is the temperature of condensed water, and t is 1 hour.

[0014] Optionally, the cooling capacity at 35°C condensing temperature can be calculated based on the cooling capacity of the air conditioner at condensing temperature T. The calculation formula is:

[0015] Among them, the value range of K is 0.03-0.05.

[0016] The present invention provides a device for detecting the performance of an in-service air conditioner. The device uses the heat generated by a heating wire to balance the cooling capacity of the air conditioner. The air blown out by the air conditioner is adjusted to the temperature and humidity state required for detection by heating and humidifying. The device is connected to the return air outlet of the air conditioner, and circulates to reach a stable state and continuously generates condensed water. The electric energy of the heating wire for 1 hour is collected by an electric energy meter, and the amount of condensed water generated by the air conditioner for 1 hour is simultaneously collected. The performance of the in-service air conditioner can be calculated based on the collected data, without the need to disassemble or assemble the air conditioner, thereby avoiding damage to the in-service air conditioner. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of an in-service air conditioner performance detection device provided by an embodiment of the present invention; Figure 2 for Figure 1 Schematic diagram of the structure of the in-service air conditioner performance detection device from the perspective of direction A; Figure 3 for Figure 1 Schematic diagram of the structure of the in-service air conditioner performance detection device from the perspective of direction B. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures. Example

[0019] Figure 1 A schematic diagram of the structure of an in-service air conditioner performance testing device provided by an embodiment of the present invention. Specifically, the device includes: an air receiving chamber, a differential pressure gauge, an air inlet port located on one side of the air receiving chamber, and a mixer located within the air receiving chamber; an exhaust chamber, multiple sets of heating wires and a humidifier located within the exhaust chamber; a return air chamber, a return air temperature and humidity probe located within the return air chamber, a return air port located on one side of the return air chamber, a mixer located within the return air chamber, and a return air motor located at the return air port; a first PID controller, a second PID controller, and a third PID controller.

[0020] See further Figure 2 There are several air pressure measuring points and static pressure pipes around the wind receiving chamber, which are connected to the differential pressure gauge through the static pressure pipe.

[0021] Among them, the air inlet port is used to connect to the air outlet of the air conditioner, the return air port is used to connect to the return air outlet of the air conditioner, and the return air temperature and humidity probe is used to detect the temperature and humidity of the return air.

[0022] The first PID controller is connected to the differential pressure gauge and is used to control the static pressure of the air outlet by adjusting the air volume of the return air motor; The second PID controller is connected to the return air dry bulb temperature probe and is used to adjust the heating value of multiple groups of heating wires to control the return air dry bulb temperature; The third PID controller is connected to the return air wet-bulb temperature probe and is used to adjust the humidification amount of the humidifier to control the return air wet-bulb temperature.

[0023] Since the temperature of the air blown out by the air conditioner is uneven, this embodiment provides two mixers to mix the air so that the air state at each location in the air duct is uniform.

[0024] Furthermore, based on the above embodiments, the present invention also provides a method for detecting the performance of an in-service air conditioner, the core of which is to balance the cooling capacity of the air conditioner with the heat generated by the heating wire, and at the same time adjust the air blown out by the air conditioner to the temperature and humidity state required for detection, and connect it to the return air outlet of the air conditioner. The cycle operation reaches a stable state and continuous condensation water is generated. The electric energy of the heating wire for 1 hour is collected by an electric energy meter, and the amount of condensation water generated by the air conditioner for 1 hour is simultaneously collected. Then, the performance of the in-service air conditioner can be calculated based on the collected data.

[0025] Specifically, the method includes the following steps: Step 1: Connect the in-service air conditioner performance testing device to the air inlet and outlet of the air conditioner and take insulation measures; Step 2: The first PID controller controls the static pressure of the air outlet to 0Pa, the second PID controller controls the dry-bulb temperature to 27°C (standard operating conditions), and the third PID controller controls the wet-bulb temperature to 19°C and powers on; Step 3: Run the air conditioner under test. When the air conditioner reaches a stable state and condensation water is continuously generated, measure the power consumption of multiple sets of heating wires for 1 hour. E , the amount of condensed water produced by the air conditioner in 1 hour G and the outdoor unit return air outlet dry bulb temperature T; Step 4: Based on the power consumption of the multiple groups of heating wires for 1 hour E , the amount of condensed water produced by the air conditioner in 1 hour G And the outdoor unit return air outlet dry bulb temperature T calculates the cooling capacity of the air conditioner at the condensing temperature T. The calculation formula is: (1) Where: Q 1 is the cooling capacity of the air conditioner at the condensing temperature T, in kilowatts (kW); E The power consumption of multiple sets of heating wires, in kilowatt-hours (kWh); t is the time of 1 hour, unit is hour h; k is the latent heat of vaporization of water, measured in joules per kilogram (J / kg). It is determined by the temperature and pressure of the air conditioner evaporator (cooling side) and can be calculated using the commonly used engineering formula k=(2501-2.38t1)×10 3 It is found that t1 is the temperature of condensed water.

[0026] G It is the amount of condensed water produced by the air conditioner in 1 hour, in kg.

[0027] The following is the process of deriving the cooling capacity of the air conditioner at the condensing temperature T: Q 1=q v ·M r v1 (2) Where q v is the cooling capacity per unit volume, in kilojoules per cubic meter (kJ / m³); M r is the mass flow rate of refrigerant, kilograms per second (kg / s); v1 is the specific volume of the gaseous refrigerant at the compressor inlet, cubic meters per kilogram (m 3 / kg); v1=V / M=1 / ρ(3) V is the volume of refrigerant vapor, in cubic meters (m 3 ); M is the mass of refrigerant vapor, in kilograms (kg); ρ is the density, which is determined by temperature and is expressed in units of (m 3 / kg); M r =η·V c N / v1 (4) η is the volumetric efficiency of the compressor; V c is the theoretical displacement of the compressor, a fixed parameter of the compressor, in units of (m 3 / s); N is the compressor speed, unit (r / s); (5) Where: C is the compressor type constant. When the compressor type is centrifugal, C≈0.01~0.02; when the compressor type is piston, C≈0.03~0.05.

[0028] P 冷凝 and P 蒸发 It can be found by looking up the refrigerant physical properties table.

[0029] is the adiabatic coefficient, a characteristic parameter of the refrigerant, which can be checked.

[0030] (6) Where: h 入 is the specific enthalpy of the refrigerant at the evaporator inlet, in kilojoules per kilogram (kJ / kg); h 出 is the specific enthalpy of the refrigerant at the evaporator outlet, in kilojoules per kilogram (kJ / kg); is the specific volume of the compressor suction port, in cubic meters per kilogram (kg / m 3 ); h 入 and h 出 ,as well as All of these can be obtained through refrigerant thermodynamic property tables or software (such as REFPROP).

[0031] From the above formulas (1) to (6), the formula for the cooling capacity of the air conditioner at the condensing temperature T can be obtained: (7) r= P 冷凝 / P 蒸发 ; The cooling capacity of the air conditioner at the condensing temperature T can be obtained by formula (1): Q 1. Calculate the cooling capacity of the air conditioner at 35°C condensing temperature according to formula (7) Q 2: (8) Where: η1 and η2 are the compressor volumetric efficiencies at condensing temperature T and 35°C, respectively, see formula (5).

[0032] Q 1 and Q 2 are the cooling capacity of the air conditioner at the condensing temperature of T and the cooling capacity of the air conditioner calculated at the condensing temperature of 35℃, in kilowatts (kW).

[0033] q v1 、 q v2 are the refrigeration capacity per unit volume (kJ / m³) at the condensing temperature T and 35°C, respectively, see formula (6).

[0034] Simplified empirical formula: (9) K is usually 0.03-0.05, and the middle value is generally 0.04.

[0035] T is the temperature condition on one side of the air conditioner condenser (radiator), which is generally 27℃-45℃.

[0036] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A device for detecting the performance of an in-service air conditioner, characterized in that: include: A wind receiving chamber, a differential pressure gauge, and an air inlet port provided on one side of the wind receiving chamber; An exhaust chamber, and a plurality of groups of heating wires and a humidifier arranged in the exhaust chamber; A return air chamber, a return air temperature and humidity probe disposed in the return air chamber, a return air port disposed on one side of the return air chamber, and a return air motor disposed on the return air port; the return air temperature and humidity probe is used to detect the dry-bulb temperature and wet-bulb temperature of the return air; a first PID controller, a second PID controller, and a third PID controller; The first PID controller is connected to the differential pressure gauge and is used to control the static pressure of the air outlet by adjusting the air volume of the return air motor; The air inlet port is used to connect to the air outlet of the air conditioner, and the air return port is used to connect to the air return outlet of the air conditioner; The second PID controller is connected to the return air dry bulb temperature probe and is used to adjust the heating value of the multiple sets of heating wires to control the return air dry bulb temperature; The third PID controller is connected to the return air wet-bulb temperature probe and is used to adjust the humidification amount of the humidifier to control the return air wet-bulb temperature.

2. The device according to claim 1, characterized in that A plurality of air pressure measuring points and static pressure pipes are arranged around the wind receiving chamber, and the wind receiving chamber is connected to the differential pressure gauge through the static pressure pipe.

3. The device according to claim 1, characterized in that Also includes: The mixer provided in the wind receiving chamber is used for mixing the air outlet temperature of the air conditioner.

4. The device according to claim 1, characterized in that Also includes: The mixer arranged in the return air chamber is used to mix the required return air temperature and humidity.

5. A method for detecting the performance of an in-service air conditioner, implemented by using the in-service air conditioner performance detection device according to any one of claims 1 to 4, characterized in that: include: Connect the in-service air conditioner performance test device to the air inlet and return air ports of the air conditioner being tested and take insulation measures; Set the outlet static pressure, return air dry-bulb temperature and return air wet-bulb temperature to the preset working conditions and power on; Run the air conditioner under test. When the air conditioner reaches a stable state and condensation water is continuously generated, measure the power consumption of multiple sets of heating wires for 1 hour. E , Condensation water volume of air conditioner in 1 hour G and the outdoor unit return air outlet dry bulb temperature T; According to the power consumption of the multiple groups of heating wires for 1 hour E , Condensation water volume of air conditioner in 1 hour G And the dry bulb temperature T of the outdoor unit return air outlet is used to calculate the cooling capacity of the air conditioner at the condensing temperature T.

6. The method according to claim 5, characterized in that The preset working conditions are: Set the outlet static pressure to 0Pa, the return air dry bulb temperature to 27℃ and the return air wet bulb temperature to 19℃.

7. The method according to claim 5, characterized in that The calculation formula for the air conditioning cooling capacity at the condensing temperature T is: ； in, E The power consumption of multiple sets of heating wires for 1 hour; G is the amount of condensed water produced by the air conditioner in 1 hour; k is the latent heat of vaporization of water, k=(2501-2.38t1)×10 3 J / kg, t1 is the temperature of condensed water, and t is 1 hour.

8. The method according to claim 7, characterized in that The cooling capacity at 35°C condensing temperature is calculated based on the cooling capacity of the air conditioner at condensing temperature T. The calculation formula is: ； Among them, the value range of K is 0.03-0.05.

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