Uniform impingement heat transfer distribution in corrugated channel with an anti-crossflow-wing

Abstract

For a further improvement of impingement jet array heat transfer in a corrugated channel, a wing-shaped structure design is proposed to weaken crossflow degradation. The naphthalene sublimation method was used to measure local heat/mass transfer distributions in the present study. Pressure drop characteristics were examined through pressure measurements. Detailed flow structures were analyzed through numerical simulations. In order to validate the superiority of the current wing structure, it was compared with the impingement heat transfer values from a typical rectangular channel and a conventional corrugated channel. The hole diameter-based Reynolds number was fixed to 10,000. The impingement distance and spacing between holes were h/d = 1 and s/d = 5, respectively. The hole patterns were designed to be in-lined in all cases. As the wing structure was added to the corrugated channel, the impingement supply flows of downstream holes became axisymmetric. The wing structure noticeably suppressed the re-entry flow from the corrugated channel back into the main/impingement channel, particularly under the downstream row of impingement holes. As a result, the overall area-averaged Sherwood number increased by about 6.4%, and the heat transfer non-uniformity in the streamwise direction was significantly reduced.