Hydrodynamics and heat transfer of pulsating flow around a cylinder

摘要

Vortex shedding and heat transfer around a cylinder in pulsating cross-flow have been studied experimentally. Analysis of flow visualization results enabled to classify flow patterns around the cylinder into four groups. New dimensionless number has been submitted, which is a ratio of the inertial force due to the oncoming flow acceleration in its global unsteady motion to the centrifugal inertial force due to curved streamlines around the cylinder. A map of flow patterns around the cylinder has been plotted in terms of the newly submitted dimensionless number and the relative amplitude of oncoming flow pulsations. Distributions of the local heat transfer coefficient over the cylinder surface depending on the flow pattern and the amplitude of forced flow pulsations have been obtained. It has been shown that forced pulsations of oncoming flow can enhance average heat transfer from the cylinder in the cross-flow.