Optimization Design of Actuator Parameters in Multistage Reciprocating Compressor Stepless Capacity Control System Based on NSGA-II

Table 2

:

Process	Differential equation
Backflow	θs3∼θ3: the plate remains stationary
	θ3∼θ4,  >
	∼θ4,  <

Note. represents the valve plate displacement, represents the crank angle, represents the instantaneous effective valve gap area of suction valve, represents the spring stiffness of valve plate, represents the ratio of specific heat of gas, represents the cylinder volume, represents the precompression of valve plate spring, represents the valve quality, represents the gas constant, represents the suction temperature, represents the coefficient of applied force of gas, represents the number of the spring, represents the inlet pressure, represents the cylinder pressure, and represents the ratio between the crankshaft radius and connecting rod length.