抄録
The sealing performance of rarefied-gas viscoseals with triangular spiral grooves is studied experimentally in order to confirm the theory previously developed by the authors of this paper, and a few experiments on the performance of the case where a net flow by pumping action exists are also performed. For the estimation of the sealing performance of seals with a net flow, the definition of the sealing coefficient which is used for seals with not net flow is expanded. The experimental results agree well with the theoretical predictions in the pressure ranges where a slip flow holds, and the expanded sealing coefficient successfully compares with the sealing performance of seals with a net flow.