Abstract
Monte-Carlo method is useful for the transmission probability calculation of a complicated-shaped tube under molecular flow conditions. However the shape data should be fed into the computer for each simulation. In the present study, transmission probability was calculated by KPCalc, which is the Monte-Carlo simulation software. KPCalc can calculate the transmission probability from the 3D-CAD data without preparing the source code of the shape data. Therefore, KPCalc is easily applied even for the complicated shape which the conventional Monte-Carlo method was hardly applied because of much labor. Calculation was carried out for cylindrical tubes, conical tubes, and bellows-shaped tubes. Results are in good agreement with previous results within the data scattering. As an example, transmission probabilities of formed bellows tubes with a complicated shape were calculated.
