Abstract
Just after starting the operation of a spinning rotor gauge at pressure less than 2 × 10-6 Pa (nitrogen equivalent), its offset pressure changed by 3 × 10-5 Pa from its final value. A simulation using a personal computer, based on a heat exchange by radiation between a rotor and a rotor tube of the gauge, is carried out to reveal the change in the offset pressure. The result of the simulation showed a good agreement with the time chart of the offset pressure measured experimentally. Influence of parameters, such as linear expansion coefficient, density, specific heat, emissivity of the rotor etc., on the time variation is also studied by the simulation.
