Simulation Platform Of The Refrigeration System And Numerical Experiments

A virtual laboratory of compression refrigeration system is established in this paper. This simulation platform includes controller, experimentation equipment of system, testing equipments of system and the four components, display equipment and experimental report. Some dynamic experiments of the heat exchangers have been done on this dummy flat. The performances of compressor, condenser, evaporator and expansion valve are analyzed and researched. The interrelated characteristic constants of compressor and expansion valve are modified and the characteristic curves are given out.The main numerical model of the system is based on the dynamic models of compressor and evaporator, as well as on the static models of condenser and expansion valve. This laboratory involves the four primary components together according to the cycle diagram. The program calculates the temperature, flowrate, density, pressure and vapor fraction at each state point in the system and the heat duty at each component. Based on this dummy flat, some influences on performance of the system caused by configuration parameters and running parameters, are analyzed.In this paper, transient mathematical models are used for condenser and evaporator. These two heat exchangers are divided into a number of control volumes. In each control volume the mass, energy and momentum conservation equations are established respectively .The details of transient parameters, vapor quality, pressure loss are considered. The simulation results are compared with the data of experiments and good agreements are found. The results indicate that the proposed models can be used to research the dynamic performances of condenser and evaporator.