Heat transfer and flow around an elliptic cylinder

Heat transfer characteristics and flow behaviors have been made clear for an elliptic cylinder of axis ratio 1 : 3. The testing fluid was air and the Reynolds number ranged from about 8000 to 79000. The angle of attack α was varied from 0° to 90°. The local and overall heat transfer features are clarified in relation to the flow behaviors around the cylinder. The critical Reynolds number is detected, where the heat transfer and flow characteristics change drastically. It is found that the mean heat transfer coefficient is at its highest at α = 60°-90° over the whole Reynolds number range studied and also that even the lowest value of the mean heat transfer rate is still higher than that for a circular cylinder. Effects of the axis ratio of the elliptic cylinder are also discussed in comparison with previous works.