Reciprocating Compressor Working Process Simulation Calculation And Experimental Study

Reciprocating compressor occupies the important position in the market，alsoconsumes huge energy. In the process of compressor operation, would inevitablyproduce energy loss, the research of the compressor cylinder internal thermal processhas great significance to save energy consumption, improve the working performancehas great significance.This article bases on the working process of the reciprocating compressor, studiesthe change laws of compressor flow field inside the cylinder, builds a mathematicmodel of the gas in cylinder motion parameters change, summarizes thermodynamicprocess in the cylinder mainly including energy conservation equation and massconservation equation, and the coupling calculation were conducted to equation ofmotion of the valve, combines the valve opening and closing condition, gas heattransfer equation and so on, the simultaneous obtaining compressor indicator diagramand the valve movement rules.The CFD simulation study on the gas in cylinder, building model based on thecylinder as a control dimension, the model can be meshed and set the piston movingevent, studying the changes of the instantaneous parameters of gas in cylinderincluding average velocity field, pressure field, turbulent kinetic energy, the averagequality, gaining the change laws of the state of gas flow in cylinder with pressure ratio,revolving speed.Build compressor test-bed for experimental study, this paper is mainly about thedetection of gas thermodynamic parameters. Test-bed develops test software throughLabview platform, operates thermodynamic parameters including rotational speed,temperature, pressure, flow, power calculation measured in the process of positivedisplacement compressor, gets the indicator diagram (p-V chart) of the compressorworking process, to observe the compressor running state and verify the results ofnumerical simulation. Comparing experiments with simulation result in the macro performance,capacity error is10.4%. Comparing the reality and theoretical p-V chart, we can getinto the power loss of exhaust process is about10%of the actual power. With theincrease of compression ratio and rotational speed, the increase of resistance loss ofgetting into the exhaust process, the decrease of air input, the increase of the averageturbulent kinetic energy and the gas speed, the volumetric efficiency and the adiabaticefficiency all showed a trend of decline. When the pressure ratio increases from2.2to3.2, volumetric efficiency decreases from0.82to0.73, and the adiabatic efficiencydecreases from0.72to0.67. When working in the cylinder, close to piston positionwhere below the inlet valve by relatively high pressure, piston ring under pressure, andprone to leakage. In the crankshaft angle295°CA, reached the highest temperature of435.7K. After angle275°CA, gas temperature more than400K, it is suggested thatincreasing cooling means.