Abstract
The flow field on the heated rotating disk is measured using ultrasonic velocity profiler method to clarify the unsteady flow structure under the mixed convection. The vortex structure is observed in the spatio-temporal radial velocity field. Two types vortex structure with difference of size and traveling velocity are found on the critical Grashof number and beyond it. The traveling velocity of one type increases with radial position cause by the centrifugal force, and another does not vary. Furthermore, the traveling velocity increases with Grashof number and decreases with Reynolds number.
