Steam compression refrigeration principle experiment table throttle device

The laboratory of the vapor compression refrigeration principle used in this laboratory adopts the type of refrigeration test bench produced by the British company. The refrigerant uses the compressor as the open type two-cylinder piston type, the condenser adopts the shell inner coil type, and the evaporator adopts the single-pass type. In the tubular type, the throttle device uses a thermal expansion valve. Condenser shell inner coil type, with sight glass, water cooling, heat transfer area expansion, cooling water maximum heat transfer amount evaporator one-way casing type, electric heater is provided in the tube to supply heat load, and its value is controlled by voltage regulating transformer . The regenerator has a countercurrent casing structure, and the central pipe is connected to the refrigerant return side.

The thermal expansion valve is controlled by the superheat of the evaporator outlet, and the degree of superheat is adjustable. System safety protection evaporator high temperature protection condensing pressure too high protection experimental principle evaporator refrigeration capacity under any working condition, when the condensing pressure and evaporation pressure remain unchanged, that is, the working condition is stable, in the evaporator, simulate the thermal load of the electric heating The amount of refrigerant vapor generated is exactly equal to the amount of refrigerant vapor pumped back by the compressor during the service condition, ignoring the heat exchange effect with the external environment. At this time, we can heat the electric heater inside the evaporator. The quantity is regarded as the cooling capacity of the compressor, that is, the difference between them is the heat dissipation of the condenser casing to the air. We can measure the external dimensions of the condenser and try to determine the heat leakage coefficient of the condenser.

When the condensing pressure and the evaporating pressure satisfy a certain experimental condition, that is, the working condition is stable, according to the suction and exhaust pressure of the compressor and the inhaling temperature, the value of the enthalpy difference between the point and the point can be found in the thermal process. According to the taste value read by the refrigerant flow meter, the Q cooling capacity, the electric heater voltage, and the electric heater current in the theoretical power formula of the compressor can be obtained, and at the same time, when the working condition is stable, the evaporation pressure can also be obtained according to the evaporation pressure. The corresponding state parameters of the refrigerant entering and exiting the evaporator are obtained from the thermogram and the value on the refrigerant flowmeter. According to the cooling capacity in the formula 2, the refrigerant circulation amount, and the evaporator inlet and outlet baking difference, the compressor refrigeration is obtained. the amount.

Condenser heat load When the condensing pressure and evaporation pressure remain the same, that is, when the working conditions are stable, the heat released by the refrigerant superheated vapor in the condenser should be balanced with the heat taken away by the cooling medium water flowing through the condenser. Heat transfer with the outer wall of the condenser At this point, the heat taken away by the cooling medium water can be regarded as the condenser load.

At the same time, when the working condition is stable, the state of the refrigerant at the time of entering and exiting the condenser corresponding to the condensing pressure and the reading on the refrigerant flow meter or the calculation of the structural parameters of the compressor according to the compressor structural parameters may also be used to indicate the power of the compressor. Open the suction valve and gradually load, let the system stabilize under the working conditions corresponding to a certain experimental condition, adjust the dynamometer, measure the reaction force value of the trunnion arm, and calculate the power condenser heat according to the torque value. The load, the amount of refrigerant circulating, and the difference between the inlet and outlet of the condenser are only the heat load of the condenser. The coefficient of cooling coefficient of performance is based on the coefficient of refrigeration performance at the input power of the motor, based on the coefficient of refrigeration at the input shaft power of the motor. Based on the coefficient of refrigeration when the compressor indicates power. The coefficient of coefficient of the theoretical coefficient of refrigeration cycle experimental method based on the above basic technical principle of the vapor compression refrigeration experimental device schematic and experimental principle, the corresponding experimental method can be developed for the refrigeration cycle without regenerator to make the reversing valve The regenerator operation position is not used, and the liquid supply bypasses the regenerator.

The refrigeration experimental device is adjusted to the specified operating conditions as required. After the working condition is stable, the temperature of the evaporator inlet, the temperature of the inlet and outlet of the condenser, and the temperature of the suction and exhaust of the compressor are recorded by the temperature measuring instrument. The flow rate of the cooling water and the flow rate of the refrigerant are recorded by a flow meter. The evaporation pressure and the condensing pressure were recorded on a pressure gauge. Record the electric heater current and voltage motor current and voltage on the ammeter and voltmeter. Record the motor torque with a side force meter. Record the compressor motor speed with a tachometer.