Recent work on the application of Electro Structured Fluids to high spped rotating machines has indicated the need for more general correlations for the prediction of heat transfer form rotating cylindrical surfaces. A numerical analysis has been made of such combined flow situations and an experimental programme has given corresponding experinment confirmation of the computed results. The analysis was two dimensional with an allowance for a swirling component of velocity around the cylinder. The maximum blowing Reynolds number, based on the length of the cylinder, The maximum blowing Reynolds number, based on the length of te cylinder, was 250,000 and the rotational Reynolds number, based on the diameter of the cylinder, varied from 3,000 to 30,000 Buoyancy effects were neglected and tubulent flow assumed, these assumptions being supported by the exprimental work. The results confirm an exponential law correlating the data. Comparisons were made with other results available for cross flow of air in which at high rotational Reynolds numbers the results are independent of the blowing effect. WIth axial flow, rotation never becomes dominant enough to make the Nusselt number independent on the blowing Reynolds number. The data was correlated by a single equation for the range of Reynolds numbers considered.
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