基于1/(ZT1)修正的五级丙烯压缩机带压启动过程建模研究及分析OA北大核心CSTPCD

According to the current process conditions,the propylene refrigeration compressor needs to be started under high pressure conditions.In order to solve the problems that the drastic change of the compressor inlet conditions during the start-up process makes the calculation of compressor performance inaccurate,the model of compressor characteristics was studied and the dynamic analysis for the start-up process was conducted.The reliability of the system modelling method was firstly verified by comparing the simulation result with the test data,the calculation error was less than 2%.Then a new compressor characteristic modelling method based on the 1/(ZT1)(Z is the inlet gas compression factor,T1 is the inlet gas temperature of the compressor)correction was proposed through theoretical derivation with both the calculation error of the pressure ratio and the efficiency calculation less than 1%,and the method was simple and easy to implement,which is suitable for the dynamic simulation study.A dynamic simulation of the five-stage propylene compressor system startup process under high pressure conditions was conducted for the preliminary startup process according to the actual operating conditions.The results show that the local power peak appears at 39 s,which is about 90%of the rated power.And it is determined that this peak power during this process is formed by the combined influencing mechanism of the redistribution of pressures at five stages and the speed increase.This peak power is a key parameter that judges whether the motor can meet the startup requirements under high pressure or not,and according to the calculated results,it can be determined that the motor selection is appropriate.The research can accurately predict the compressor performance and provide guidance for accurate component selection.