Experimental Discussion on the Efficacy of Loop Refrigeration Air Compressor

When the working volume is reduced, the gas inside is compressed and finally discharged from the intermediate exhaust port. The figure shows the situation when the moving scroll rotates clockwise every other corner. The working process of the scroll compressor includes three processes of suction, compression, and exhaust, and the three processes are performed simultaneously.

Due to the special structure of the scroll compressor and the working process different from the general volumetric compressor, it has the following characteristics: less leakage during the compression process and high efficiency. The scroll compressor has a compression chamber with an intermediate pressure between the suction and exhaust chambers, so that the pressure difference between the adjacent compression chambers is small and the leakage is small, and the pressure difference is the smallest compared with the piston type and the rotary type compressor.

In addition, the vent hole is not in communication with the low pressure side, so that there is no re-expansion phenomenon like the piston type. The basic structure of the scroll compressor is small, the vibration is small, and the suction, compression and exhaust processes of the low-volume compressor are simultaneous. And continuously, the pressure rises more gently, so the torque change is small, and the inertial force is almost balanced, and the vibration of the compressor is small.

In addition, the gas flows almost continuously, the change in the exhaust pressure is small, the vibration energy on the pipe is small, and the compressor can be provided with no suction and exhaust valves, so that the overall noise is greatly reduced. Small size, light weight and good reliability.

The scroll has a compact structure, a simple transmission mechanism, and no suction and exhaust valves. Therefore, the compressor is small in size and light in weight, and there are no problems such as flow loss, noise, and broken valve plates caused by the gas valve, and the reliability is good. Small wear resistance and good resistance to “liquid shock”. The scroll compressor uses an intermediate pressure on the back of the moving scroll to balance the axial force, so that the axial clearance is small, and the radial leakage of the gas can be prevented. The working condition is automatically adjusted, the moving plate is in suspension state, and the friction loss is small. When the non-compressible liquid such as refrigerant and oil is abnormally compressed, the performance test of the prototype of the functional test device that automatically disengages the moving plate to prevent abnormal high pressure is in Changsha Railway. The refrigeration and air-conditioning laboratory of the college completed the test according to the "Performance Test Method for Positive-Voltage Refrigeration Compressor". The test device was tested with the second refrigerant-dose heat method, and the auxiliary test was performed with the water-cooled condenser calorimeter method. These two methods have measurement accuracy. High, adjustable amplitude and convenient adjustment.

The complete set of test equipment is designed and installed by itself. The test equipment is shown in the figure below. The temperature metering device consists of a set of direct evaporating coils that are suspended in an upper part of a pressure-resistant insulated container, and an electric heater is mounted on the bottom of the container. A second refrigerant knives is placed in the vessel, and the electric heater is immersed in the second refrigerant.

In order to reduce the influence of external heat, the refrigerant connecting pipe of the expansion valve and the calorimeter is insulated and calibrated on site, and the heat leakage coefficient of the calorimeter is much lower than the standard that does not exceed the refrigeration capacity of the compressor. Good thermal insulation performance Water-cooled condenser is one of the equipments that make up the compressor test system. It is insulated with the entire condenser as a secondary measuring heat meter together with a measuring instrument that can meet the standard accuracy of temperature, pressure and cooling water flow. , its heat leakage coefficient.

Test Results The performance test of the prototype is carried out in strict accordance with the test procedure. The flow rate of the refrigerant in the test system is adjusted by the manual expansion valve installed near the calorimeter for coarse adjustment and fine adjustment, so as to achieve the purpose of accurately adjusting the suction pressure of the compressor. The suction temperature of the compressor is adjusted by changing the amount of electric heating to the second refrigerant. The discharge pressure of the compressor is adjusted by changing the condenser cooling water flow rate and temperature.

During the test, the heating power of the entire power supply through the automatic regulator electric heater is adjusted by the voltage regulator to ensure the calculation formula of the main measured flow rate of the test accuracy. The ratio of the refrigerant before the expansion valve corresponding to the exhaust pressure is the actual specific volume of the refrigerant at the suction port of the compressor, and is the specific volume of the refrigerant at the suction port of the compressor under the specified operating conditions. The actual measured data of the auxiliary test, calculate the cooling capacity, and the difference between the two tests in each working condition is within the range. The main performance parameters of the compressor test conditions are shown in the attached table.

Conclusion The development of the prototype is successful, and all performance indicators have met the design requirements. After nearly a long period of operation and full laboratory performance tests, it has high reliability and good starting performance.

Gas Generator

Generators, Diesel Generator,Gasoline Generator,Gas Generator

Diesel Engine Water Pump,Generator Sets Co., Ltd. , http://www.nbdieselengine.com