Local heat transfer around a wall-mounted cube at 45° to flow in a turbulent boundary layer

Abstract The flow and local heat transfer around a wall-mounted cube oriented 45° to the flow is investigated experimentally in the range of Reynolds number 4.2 × 10 3 –3.3 × 10 4 based on the cube height. The distribution of local heat transfer on the cube and its base wall are examined, and it is clarified that the heat transfer distribution under the angled condition differs markedly to that for cube oriented perpendicular to the flow, particularly on the top face of the cube. The surface pressure distribution is also investigated, revealing a well-formed pair of leading-edge vortices extending from the front corner of the top face downstream along both front edges for Re >(1−2)×10 4 . Regions of high heat transfer and low pressure are formed along the flow reattachment and separation lines caused by these vortices. In particular, near the front corner of the top face, pressure suction and heat transfer enhancement are pronounced. The average heat transfer on the top face is enhanced at Re >(1−2)×10 4 over that of a cube aligned perpendicular to the flow.

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