The Comparison On Heat Transfer Performance Of Condenser With R290 And R22 For Refrigerant

The study on green, environmental-friendly refrigerants and enhanced heat transfer technology are currently very important research subjects. On the 2010 international seminar on air conditioner HCFCs substitute technology three domestic air conditioner makers including Gree , Media and Haier shared their research achievements on 290. The experimental results of these air conditioner companies show that R290 enjoys very good cooling function as R22 does, and it will be of great significance to study its function with its promising future.At present, the global environmental problem is still the focus at home and abroad. To protect ozone layer and avoid worsening global climate, higher requirement for refrigerants are proposed and paid more and more attention by researchers and engineers in refrigerating and air conditioning industry.This paper summarized the development of R22 alternative refrigerants. The advantages and disadvantages of R290 which is a natural substance for R22 are analyzed. The circulation performance was compared between these two mediums. The following research has been carried out.1. The refrigeration cycle properties of R290 and R22 were calculated simply and quickly based on the developed program. In standard conditions or changing conditions, refrigeration performance parameters for R290 are similar with R22’s, which proved that R290 can be used as an alternative refrigerant for R22. The drop-in amount of R290 is 53.9 % of R22. R290 and R22 share almost the same function. The theoretical coefficient of refrigeration and efficiency will increase while the evaporating temperatures increase, whereas the increasing of condensing temperature will show the opposite results.2. The steady-state distributed parameter model for condenser is established, and the computer simulation program was developed in MATLAB language. The heat transfer performance for R290 and R22 condensers are studied, including temperature distribution and heat transfer coefficient. The results lay a preliminary foundation for the design of heat exchanger using R290.The simulation shows that with the condensing structure and the operation of the compressor unchanged, heat transmission coefficient of R290 will be a little larger than R22 is, while transferring almost the same amount of heat.3. Moreover, the influence of different finned spacing, wind speed and refrigerant flow on performance of heat exchanger were studied in this paper. At the same heat load, the condenser area was calculated with R22 and R290, respectively. It showed that the area with R290 is smaller than that of R22 at given mass velocities. The methods and conclusion of this paper are useful to the research and development of heat exchangers with R22 substitutions.