Heat transfer from a circular cylinder in a pulsating crossflow

Abstract

The effects of organized well-defined harmonic disturbances in the mean crossflow on heat transfer from a circular cylinder were experimentally determined. Local, time-averaged heat transfer data at constant wall temperature is reported for Reynolds numbers between 3 x 104 and 9 x 104. Pulsation amplitudes were generally small (<10 per cent) with frequencies up to and beyond the frequency of natural shedding. Small increases in heat transfer all around the cylinder are found in pulsating flow. point. More significant increases occur near the separation point. A convection calibration for the circular foil heat flux gage used in the heat transfer experiments is included. The convection calibration shows a non-linear gage response for a 'hot' gage in a convection environment. This is in contrast to the linear calibration curve produced by the standard 'cold' gage radiation technique.