The Numerical Study on Evaluating the Safety of Refrigerant Leakage for a R290 Air-Conditioner

• Main Authors: Rih-Cheng Cheng, 程日城
• Other Authors: Yang-Cheng Shih
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/u7a77h

碩士 === 國立臺北科技大學 === 冷凍空調工程系所 === 103 === Refrigerant R290 possesses the characteristics of non-ozone layer depletion and low global warming potential (GWP). But, it belongs to the combustible refrigerant and it could cause a fire accident or explosion. This study used the numerical simulation to evaluate the safety of refrigerant leakage for a R290 air-conditioner. The CFD package software, ANSYS FLUENT, was employed to simulate the diffusion process of the leaking refrigerant within an indoor. During the CFD simulation, two leakage positions were considered: one was set at the pipe connector joining the inside and outside units, and the other was set at the return tubes of evaporator inside the indoor unit. In addition, the on and off of the compressor and the exhaust fan were also considered as the operating conditions. Comparing the numerical results with those of the experiment in literature, it can be found that both results had similar trend on the concentration distribution of R290. The numerical results also show that it is beneficial to lower the indoor R290 concentration when the exhaust fan was turned on. Moreover, avoiding the occurrence of flow circulation can reduce the accumulation of R290, causing that the rise of R290 concentration.