Effectiveness enhancement of non-contact vacuum pumps working process

Three options of rotor profiles of Roots vacuum pump are considered: elliptic, circular, and involute. Rotor profiles are drawn in the same housing and are analyzed from point of view of backward leakage minimization through inter-rotor channel and geometric pumping speed increase. It is shown that coefficient of working volume use is only 3% higher for involute profile. Averaged over one revolution conductance of rotor mechanism channels is minimal for elliptic rotor profile. For inter-rotor channel it is 14% less than for involute profile. The presented approach makes it possible to choose the optimal rotor profile of Roots pump for particular purpose.