Dtube 3[mm] Tube diameter Ltube 30[mm] Tube length T0 300[K] Temperature of system Mn0 0.04[kg/mol] Molar Mass mu0 22.9e-6[Pa*s] Viscosity of gas pa_inf 1e-4[torr] Reservoir pressure (low vacuum) alpha 1 Tube accomodation coefficient Spump 500[l/s] Pump speed