Comparison and Validation of Semi-empirical Compressor Models for Cycle Simulation Application

摘要

During development of refrigeration cycle simulations, the modelling of the compressor requires a trade-offrnbetween computational speed and level of detail. In that case, the use of semi-empirical models makes senserninstead of complex 1-dimensional models which are common in the development phase of a compressor. Alsornthe very low measuring effort for the adaption of these models favours their use.rnThe present work contains a comparison of different semi-empirical models found in the literature whichrnsimulate the dynamic performance of reciprocating compressors. These models calculate the refrigerant massrnflow rate and the compressor power based on polytropic compression and the formulation of a volumetricrnefficiency. The model parameters are determined by fitting calorimeter data of two compressors. To validate therntransient prediction-capability of compressors by these models, start-up and cycling measurements were carriedrnout and compared with the computed data. Due to the common requirements in cycle simulation tools, a modelrnfor the discharge temperature was developed and validated additionally.rnThe goal of the present study is to find a combination of accurate models of mass flow rate, compressor powerrnand discharge temperature which can be applied to cycle simulations of the whole refrigeration system.