Abstract:

With good thermal performance and environmental characteristics, R32 is a candidate for replacement of R22, but it is not adopted because of its slight flammability. This paper, in the view of indoor security, analyzes the leakage variation and the effect of supply air velocity and angle on the concentration distribution when the refrigerant leaks from the indoor unit with the air conditioner operating. The experimental results show that the refrigerant leakage rate decreases with time when the air-conditioning system works. The refrigerant leakage can be classified into two stages, fast leak and slow leak. Indoor environment security is evaluated and the results show that the combustible zone only appears near the leakage hole and its residence time is very short. Thus the risk level of using R32 as the refrigerant of air conditioner is low with the air conditioner operating.

Key words: R32, leakage, supply air velocity, supply air angle, convection, diffusion, security

摘要：

R32以其良好的热力性能和环保特性成为了极具潜力的替代制冷剂, 然而其可燃性制约了它的广泛应用。从可燃性冷媒R32的泄漏扩散对室内安全性影响的角度出发, 采用实验研究的方法, 探索空调运行条件下制冷剂泄漏规律及空调送风速度和送风角度对室内R32浓度分布的影响。分析结果表明, 空调运行时制冷剂泄漏速率随时间逐渐降低, 泄漏过程可以分为高速泄漏阶段和低速泄漏阶段;分析空调送风速度和送风角度对室内R32浓度分布的影响, 得到不同送风工况下室内R32的浓度分布规律;对制冷剂泄漏条件下室内环境安全性进行评价, 结果表明在R32开始泄漏的很短时间内, 泄漏口附近出现可燃区域, 但可燃区域滞留时间很短, 危险性较小。

关键词: R32, 泄漏, 送风速度, 送风角度, 对流作用, 扩散, 安全性