Particle Image Velocimetry of Turbulent Mixed Convection at Ambient and High Pressure

Abstract

Measurement of turbulent mixed convection at reduced model size by aerodynamic scaling is a promising approach to simplify the investigation of many technical configurations and offers the potential to make large scale flows accessible on a laboratory scale. On the pathway to measurement of turbulent mixed convection at high pressure by Particle Image Velocimetry forced, free and mixed convection have been investigated in a generic convection cell at ambient pressure. The scaling theory, which allows to down scale the cell, is presented, the PIV set up used for measurement at high pressure conditions in the high pressure wind tunnel in Göttingen is discussed, and the cell, which is capable of being operated at high pressure, is reviewed. Finally, first results of measurements at ambient pressure in a closed loop open test section wind tunnel at Re = 3500, Gr = 9 · 10⁵, Pr = 0.7 and Ar = 0.4 are discussed.