Study on Clearance Optimization of All-metal Screw Pumps: Experiment and Simulation
Due to the advantages of heat and wear resistance, all-metal screw pumps have been commonly applied in field tests in recent years. In this work, the methods of thermodynamic and computational fluid dynamic were applied to analyze the effects of temperature and viscosity on clearance between rotor and stator of the all-metal screw pump. The clearance between stator and rotor of the all-metal screw pump has been optimized. Different model machines of the all-metal screw pump with different clearances have been manufactured, and numerous tests have been carried out in laboratory and fields in order to analyze the effects of rotational speed and viscosity of medium on the characteristics of the all-metal screw pumps. Results show that the performance of all-metal screw pumps is compared with that of rubber screw pumps. Results show that the medium viscosity and rotational speeds have significance effect on pump efficiency. An increase in the pump efficiency could be achieved with an increase in the rotational speed. However, compared with the rotational speeds, the viscosity of medium shows a more severe influence on the pump efficiency. Characteristics of the newly developed all-metal screw pumps could satisfy design requirements. Characteristics of the all-metal screw pumps consistent with the results of laboratory experiments, and operation processes are smooth and reliable. This article provides a theoretical guidance to the promotion and application of this technology.