Conductance calculation of slot channels in laminar gas flow regime at small pressure difference

In vacuum systems gas flows not only through slot channels with constant cross section but also through slot channels with variable cross-section. The relationship obtained analytically for the conductance calculation of three types of slot channels in viscous flow regime at small pressure difference at the ends of the channel is presented in this paper. This relationship is recommended for the calculation of flow rates in vacuum systems channels with variable cross-section with a minimal clearance at a certain point along their length. The experimental study of slot channels conductance was carried out.

► Gas flow through channels formed by cylindrical walls is considered.
► A simple relationship for viscous flow conductance was obtained analytically.
► It is used for gas flow in channels with fixed walls at small pressure difference.
► Conductance for various walls radii and clearances was obtained experimentally.
► The agreement between the calculated values and experimental data is within 7%.