气阀动力特征参数对活塞式压缩机示功图的影响

Influence of Valve's Dynamic Parameters on PV Diagram for Reciprocating Compressor

在一定的假设条件下,建立往复式压缩机工作过程数学模型,编程求解并绘制出热力过程P-V示功图;研究了气阀动力特征参数对压力曲线的影响,并给出特定工作条件下气阀参数的最优组合;研究结果表明:吸气阶段,阀片质量越小,气缸最小压力升高,阀片开启时间越短,不易出现滞后启闭现象;弹簧刚度系数与最小压力及阀片启闭关系不显著,系数越大,曲轴转速越低,越易引发"颤振"现象;弹簧预压缩量越小,弹簧个数越少,愈易引起阀片滞后关闭,此外,弹簧刚度越大时,这种影响越显著。

Under assumed conditions, a mathematical model of a reciprocating compressor working process is established, resolved by mathematical programming and the PV diagram is drawn. The influence of the valve＇ s dynamic parameters on the volume/pressure curve is analyzed, and the optimal combination of valve parameters under certain working conditions is presented in this paper. The research results reveal that a smaller valve mass results in a higher minimum pressure inside the cylinder during suction. The shorter valve opens, it＇ s more rare to delay opening and closing. Valve stiffness has little effect on the minimum pressure and the delay of valve opening and closing. The chattering phenomenon is more likely to occur with increasing stiffness coefficient and decreasing rotational speed. The delay time of valve closing is in inverse proportion to spring pre-compression and the number of valve spring, while being proportional to their stiffness coefficients.