Affiliation:
1. University of Sciences and Technology Houari Boumediene
2. Laboratory of Industrial and Human Automation Control, Mechanical Engineering and Computer Science
Abstract
Abstract
The present work analyzes a fully turbulent wall jet flow cooling a heated wall downstream a backward facing step. The experiment combines dynamic and thermal measurements in order to study the detailed of such flow. The test matrix involves several aspect ratios (AR), varying from 2.61 to 11.33, obtained by changing the step height as well as different turbulent Reynolds (Re) numbers up to 22700. Data are collected using a hot wire anemometer and an infrared thermal camera. The results show that the position of maximum heat transfer xmax becomes farther as the AR gets smaller, but is independent of Reynolds numbers for the considered range. The Reynolds number effect on maximum Nusselt number (Numax) is also presented. The side walls effect on heat transfer downstream the backward facing step is found to become more significant as much as the aspect ratio is smaller. Correlations relating heat transfer parameters to Re and/or AR are also presented.
Publisher
Research Square Platform LLC
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