Pressure Loss of Gaseous Flow at Microtube Outlet

The pressure loss of gaseous flow at a micro tube outlet was investigated numerically. The numerical methodology is based on the Arbitrary-Lagrangian-Eulerian (ALE) method. Axis-symmetric compressible momentum and energy equations are solved to obtain the pressure loss coefficient of gaseous flow at a micro tube outlet. Computed tube radiuses are 25, 50 and 75 μm. The stagnation pressure of upper stream of the tube is chosen in such a way that the Mach number at the tube outlet ranges from 0.1 to 1.3. The ambient (back) pressure is fixed at the atmospheric pressure. The pressure loss coefficients are compared with available experimental data for a conventional sized tube. The effects of the Ma number and the tube radius on the pressure loss coefficient are discussed and the correlation for the pressure loss coefficient is proposed.