Designs, analyses, and tests of a spiral-grooved turbobooster pump

This article shows a spiral-grooved turbobooster pump, which has a momentum transfer-type vacuum pump function, and is capable of operation in a disch arge pressure range up to 1000 Pa. Transitional flow pumping speeds are imp roved by a well-designed midsection clement. Pumping performance of this ne w pump is predicted and examined by both of the computational fluid dynamic s method and the direct simulation Monte Carlo method. These two complement ary approaches are successfully being used to investigate the whole pumping speed curve from the viscous high-pressure to the molecular low-pressure r ange. Also, the developed Dump is tested on an evaluation system constructe d according to JVIS-005 standard. Good agreement between analytical results and experimental data are shown. Furthermore, to achieve a clean, safe, an d reliable pumping process, this pump is designed with and operated by an i nnovative digital magnetic-bearing system. (C) 2000 American Vacuum Society . [S0734-2101(00)03303-0].