Total Temperature Measurements of Gaseous Flow at Micro-Tube Outlet: Cooled From the Wall
This paper presents experimental results on heat transfer characteristics of gaseous flow in a micro-tube with constant wall temperature whose wall temperature is lower than the inlet temperature (cooled case). The experiment was performed for nitrogen gas flow through a micro-tube with 163.4 micro meters in diameter and 50 mm in length. The gas was heated at the inlet of the micro-tube to Tin = 315K, 335K and 355K. The wall temperature was maintained at 305K which was lower than the inlet temperature by circulating water around the micro-tube. The stagnation pressure was chosen in such a way that the exit Mach number ranges from 0.1 to 0.9. The outlet pressure was fixed at the atmospheric condition. The total temperature at the outlet, the inlet stagnation temperature, the mass flow rate, and the inlet pressure were measured. The numerical computations based on the aribitary-Langrangian-Eulerian (ALE) method were also performed for the same conditions of the experiment. The total and bulk temperature obtained by the present study are compared with those of the numerical cases and also compared with temperatures of the incompressible flow. The results have similar trends.