Flow Field Investigation And Pumping Efficiency Research On Two-stage Rotary Vane Vacuum Pump

Rotary vane vacuum pump is a fundamental equipment in vacuum technology, It is provided with great significance to have a deep research into the rotary vane vacuum pump. The pumping efficiency is one of the important performance index of the rotary vane pump, improving pumping efficiency can reduce the pumping time substantially, helping to reduce the cost of production and so it is what a rotary vane pump users highly care about Compared with the foreign products, there is a big gap between the domestic and abroad pump in the respect of pumping performance. In order to improve the performance of domestic pump and to narrow the gap with foreign pump, improving the pumping efficiency appears to be with great significance.The pumping efficiency and internal flow field analysis based on the VRD-16 series two-stage rotary vane pump as the main research direction in this paper, calculating theory pumping speed. Using the 3d drawing software Pro/ENGINEER and computational fluid dynamics software Fluent,by grid motion technology, numerically simulate high vacuum pump chamber, channel between high and low vacuum level and the entryway.Compared with the theory pumping speed, the result of simulation to two-stage rotary vane pump is feasible.Fluent software can simulate two-stage rotary vane pump,verifying the result of simulation to is feasible.these are aimed to base on internal flow field simulation and analysis of the two-stage rotary vane vacuum pump.After analyzing the results of gas flow characteristics in the channel between high and low vacuum level, velocity value and pressure value of gas are changed a lot on variable cross-section of the channel. Through changing the structure of channel, the structure parameters on variable cross-section of channel influence pumping efficiency of VRD-16 series two-stage rotary vane vacuum pump, when the cross-sectional area through prevents gas discharge and reduces pumping efficiency of rotary vane pump.Based on researching and analyzing internal gas flow characteristics of two-stage rotary vane pump, the suction chamber of original model has an early end work before reaching max volume. Changing inlet structure of original model, analyzing internal flow field distribution the inlet structure parameters can influence gas flow characterics and pumping efficiency.Comparied with simulation results of different gap values and different temperatures on high vacuum chamber. Wall temperature and the clearance value is the main factor that impact pumping efficiency in the lower inlet pressure. The pumping efficiency will be reduced by the higher pump wall temperature and the bigger clearance value.This paper also studied internal gas flow characteristics in the oil baffle, a major cause of its internal gas spiral is caused by oil baffle wall structure, so should reduce arc wall structure and gas energy dissipation in the oil baffle.