Experiments on Turbulent Floe in a Duct Affected by Diamond Obstacles with Aligned and Staggered Arrangements

Nashee, Sarah Rabeea

doi:10.22075/jhmtr.2025.35946.1640

Experiments on Turbulent Floe in a Duct Affected by Diamond Obstacles with Aligned and Staggered Arrangements

Document Type : Full Length Research Article

Author

Sarah Rabeea Nashee

Department of Mechanical engineering. College of engineering, University of Thi-Qar, Thi-Qar. 64001, Iraq

10.22075/jhmtr.2025.35946.1640

Abstract

The convection heat transfer flow of air in a rectangular duct with and without diamond obstacles arranged in two ways (aligned and staggered) was experimentally examined in this work to examine the performance of the duct with and without the presence of obstacles and the impact of these obstacles on the enhancement of heat transfer in the duct. The purpose of the diamond obstacles was to enhance heat transfer within the duct. A variety of turbulent conditions were utilized for the tests. (Reynolds number=10000–35000). Pitch to obstacle height ratios of 4, 5, and 6 were employed with aluminum barriers at height ratios of 0.16, 0.25, and 0.3. According to the experiments' findings, these barriers improved heat transfer by enhancing the mixing process between air and the heated walls. This is seen when the obstacles are applied with obstacles height to duct height (e/H) = 0.3 and pitch to obstacle height (p/e) = 6 for the two configurations. The staggered configuration is thought to provide the best enhancement of thermal performance, equal to 174 % at Re = 10,000, while the aligned arrangement is 156% under the same conditions. That means that the staggered arrangment is better than the aligned case. Regarding the pressure drop, the findings demonstrate that the staggered arrangement yields the highest friction factor values for all investigated velocities, as well as the highest values for the elevation and pitch ratios; it reaches 0.14 at a Reynolds number = 10,000 for staggered and 0.122 for aligned. These findings demonstrate that staggered diamond barriers dramatically enhance turbulence and heat-transfer rates with tolerable pressure penalties, giving essential experimental data for compact heat-exchanger design.

Keywords

Diamond obstacles

turbulent flow

Thermal enhancement

Friction factor

Subjects

Free Convection

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