Variable Refrigerant Flow Air Conditioning System Dynamic Simulation And Performance Study

The core technology of the digital scroll air conditioning system is the digital scroll compressor. The digital scroll air conditioning system is consisted of indoor unit, outdoor unit, refrigerant pipe and remote control equipment. With the development of the living condition and popularization of the air conditioning system, its operationg performance and energy consumption were considered by people. Systematic research of air conditioning system was studied in the paper. At first, a dynamics model of the air conditioning system was proposed in the paper. The compressor model was based on the steady lumped parameter method. The electrical expansion valve model was based on the lumped parameter method. Self-defining function curving fitting method in Origin program was first used in the thermal properties calculation of the environmentally-fridendly refrigerants. A simple and convenient method based on the Cleland equations was proposed to calculate thermal properties of refrigerants R410A and R407C which are known as two main substitutes of R22. The calculating results were compared with the data from the literature and the errors were acceptable. Compared with other thermal properties calculation model, the method has greater computation speed. The calculation results with minor error indicated that this method is an effective method for studying the thermal propertied of the refrigerant substitutes. Calculation and comparison between the fan-coil add new air system and VRV system were proposed in the paper. The results were that VRV air conditioning system has more efficiency than the fan-coil system. In the partial load condition, the digital scroll can realize no steps energy regulating and have higher efficiency.