RAYLEIGH NUMBER DEPENDENCE OF THE ARCHIMEDES NUMBER DEPENDENT LARGE-SCALE FLOW STRUCTURE FORMATION IN MIXED CONVECTION

etc15 Tracking Number 455

We report on experimental investigations of large-scale flow structure formation in mixed convection. We characterize the flow field by measuring the velocity fields within a rectangular model room using 2D2C PIV. The control parameters are the Reynolds number Re, the Rayleigh number Ra and the Prandtl number Pr. All parameters are linked through the Archimedes number Ar. In 6.410-2 ≤ Ar ≤ 1.39101, 4.2103 ≤ Re ≤ 6.35104 and Ra = 3.1107, Ra = 1.8108 and Pr = 0.713 we found flow 3 different flow structures. While keeping Ra and Pr constant and varying Ar through Re variations, we found an Ar dependence of the largescale flow structure formation within 6.410-2 ≤ Ar ≤ 1.39101. Furthermore, we found a Ra dependence of the structure formation, which shifts the transition points between the structures to higher Archimedes numbers and reduces the mean velocities within the investigated domain.