Thermodynamic Prediction Model of Single-stage Gradational Lead Screw Vacuum Pump

Abstract

As a kind of fluid machinery, screw vacuum pumps are widely used in material engineering and semiconductor industry. Nowadays, new requirements for screw vacuum pumps are put forward on low energy consumption and low manufacture cost. Compared with the constant lead screw (CLS) vacuum pump, the gradational lead screw (GLS) vacuum pump has many advantages. Taking the SGLS vacuum pump as the research object, this paper divides the pumping process into four small stages and proposes a thermodynamic model to analyse the performance. The characteristic curves under diverse operating conditions are drawn and the energy consumptions are illustrated at the end of this paper. The results show that a thermodynamic model can provide a well explanation on the phenomena of pressure pulsation and power consumption, which will help us to understand the outstanding performance of SGLS vacuum pump better.