Abstract:

According to the application demand like electrical cooling, an R290 linear compressor prototype is designed and developed for small scale refrigeration unit. The performance of this compressor is investigated under different working conditions. On the condition of 8.0, 2.7 and -3.4℃ evaporating temperature,the cooling capacity at TDC of the linear compressor is 1633.4, 1417.4 and 943.4 W, respectively. COP is 6.67, 4.24 and 2.63, respectively. Correspondingly, the cycle efficiency is 67.5%, 70.9% and 69.3%, respectively and the efficiency on the rate condition is higher than the others. When the cooling capacity changes from 35% to 100%, the polytropic index ranges from 0.968 to 0.983. During the process of capacity adjustment, the equivalent gas spring, natural frequency and equivalent damping change nonlinearly with the piston stroke and has an extremum at the TDC.

Key words: R290, linear compressor, variable operating conditions, thermodynamics, kinetic theory

摘要：

根据电子冷却等应用需求，开发了小型制冷装置用R290直线压缩机样机，并开展了变工况性能试验研究。结果表明，在蒸发温度为8.0、2.7和-3.4℃三种工况下，直线压缩机在上死点位置的制冷量分别为1633.4、1417.4和943.4 W，COP分别为6.67、4.24和2.63，对应的循环效率分别为67.5%、70.9%和69.3%。蒸发温度2.7℃的设计工况循环效率最高，该工况下，当制冷量在35%～100%调节时，多变指数系数变化范围为0.968～0.983。在压缩机变容量调节过程中，气体等效刚度、固有频率与等效阻尼呈非线性变化，在上死点附近均存在极值点。

关键词: R290, 直线压缩机, 变工况, 热力学, 动力学理论