An experimental and numerical analysis of refrigerant flow inside the suction muffler of hermetic reciprocating compressor

摘要

In this study, detailed temperature and pressure measurements were performed at the inlet, outlet and outerrnboundaries of the suction muffler of a hermetic reciprocating compressor. The measurements were conductedrnwithout effecting real phenomena. After experimental studies, detailed computational fluid dynamic analysis ofrnthe refrigerant flow (isobutane) in the suction muffler was performed. Experimental pressure and temperaturernvalues at the inlet, outlet and outer boundaries of the suction muffler were used as boundary conditions. Therneffect of suction valve (opening and closing) at the exit of the suction muffler has been considered. 3-rndimensional time dependent calculations were completed when statistically steady state convergence wasrnreached for one crank period. Realizable k-є turbulence model with appropriate parameters, second orderrndiscretizations for time and space derivatives and real gas model for isobutane (R600a) were applied for thernnumerical analysis. Mesh dependency of the analysis and solver algorithms were also investigated.rnThe results of the numerical analysis has shown that the time integrated average of the numerically calculatedrnmass flow rate is close to average mass flow rate measured with a calorimeter test system. Furthermore thermalrnmapping inside the suction muffler shows good agreement with experimental results. Time dependent flowrnanalysis results inside the suction muffler help to characterize the flow and acoustic function of the mufflerrnwhich leads to the new and better muffler designs.