两级单螺杆压缩机气体阻力矩变化特性研究

A Study of Gas Resistance Torque Variation Characteristics of Two-stage Single Screw Compressors

为了减小两级单螺杆压缩机电机负载转矩的波动,基于单螺杆压缩机力学特性,建立了两级单螺杆压缩机串联螺杆转子的力学模型,研究了串联螺杆转子的气体阻力矩变化特性,计算分析了空气质量流量为40.6 kg/m^(3)的两级串联单螺杆压缩机在不同排气压力下的气体阻力矩波动比,并与任意一级独立运行的单螺杆压缩机的气体阻力矩波动比进行了比较。研究结果表明:对于工质质量流量为固定值的单螺杆压缩机,存在确定的压比,使其气体阻力矩波动比最小;两级串联单螺杆压缩机的气体阻力矩波动比小于其中任意一级独立运行的单螺杆压缩机的气体阻力矩波动比;在两级串联单螺杆压缩机中,一、二级螺杆转子间初始相位差对单螺杆压缩机总气体阻力矩的波动幅值有影响,并存在一个最优初始相位差,使总气体阻力矩波动幅值最小。该研究结果对两级单螺杆压缩机设计以及进一步发展具有一定的指导意义。

In order to reduce the fluctuation of motor load torque of two-stage single screw compressor,based on the mechanical characteristics of the single screw compressor,a mechanical model of the two-stage tandem screw rotor is established and the fluctuation characteristics of its gas resistance torque is studied.The torque fluctuation ratio of the two-stage tandem single screw compressor with air mass flow rate of 40.6 kg/m^(3) under different exhaust pressure is calculated and analyzed,and then compared with that of any single screw compressor running independently.The results show that for a single screw compressor with a fixed mass flow rate,there exists a definite pressure ratio,which leads to the smallest gas resistance torque fluctuation ratio.The two-stage single-screw compressor with tandem operation is more stable than that with the parallel operation.Moreover,in the two-stage tandem single screw compressor,the fluctuation amplitude of the total gas resistance torque is significantly influenced by the initial phase difference between the first and second screw rotor,and there always exists the minimum value caused by an optimal initial phase difference.The above research results have certain guiding significance for the design and further development of two-stage single screw compressor.