Development of disturbances in laminar and transition regions of free convection boundary layer along a vertical plate

The downstream growth of velocity and temperature disturbances in the laminar and transition regions of the free convection boundary layer along a vertical plate with uniform heat generation in the air was experimentally studied, using a fine thermocouple and LDV. The beginning and end of the transition were determined by the vertical temperature distribution on the heated plate, which was maximum at the beginning and minimum at the end of the transition. Modified Grashof numbers at the beginning vary widely, but those at the end of the transition can be approximated by about 5×(10)^<12>. The maximum intensities of the streamwise velocity and temperature across the boundary layer reach maximum at the end of the transition and become roughly half of each streamwise maximum intensity at the beginning of the transition.