Heat Transfer Measurements from Concave and Convex Surfaces with a Fully Developed Confined Impinging Slot Jet

In paper the experimental and numerical modeling results of a heat transfer in annular channels with continuous twisting at one-phase water flow are presented. For a flow twisting the wire was spirally coiled on the central body of an annular channel (diameter of a wire is equal to annular gap height). The generalizing associations for heat transfer calculation on the concave and convex surfaces in a single-phase phase are presented. The analysis of features of velocity profiles and temperatures on the concave and convex surfaces are carried out. The heat transfer on a convex surface of an annular channel with a twisting considerably above than the heat transfer on a concave surface. It’s caused by increase of displacement of a maximum of a velocity profile to a concave surface under the influence of mass forces with growth of a twisting extent.

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Viscous interaction over concave and convex surfaces at hypersonic speeds

Journal of Fluid Mechanics ◽

10.1017/s0022112072001715 ◽

1972 ◽

Vol 55 (1) ◽

pp. 163-175 ◽

Cited By ~ 8

Author(s):

S. Mohammadian

Keyword(s):

Heat Transfer ◽

Boundary Layer Thickness ◽

Curved Surfaces ◽

Cold Wall ◽

Oscillatory Behaviour ◽

Convex Surfaces ◽

Viscous Interaction ◽

Hypersonic Boundary Layers ◽

Hypersonic Speeds ◽

Interaction Equation

The growth of hypersonic boundary layers over both concave and convex surfaces is described, the strong-viscous-interaction equation due to Cheng et al. (1961) for curved surfaces with sharp leading edges being solved asymptotically for small and large arguments. Both the asymptotic solution for large arguments and a numerical integration predict an oscillatory behaviour of the boundary-layer thickness on concave surfaces. A modification of Cheng's theory, as suggested by Sullivan (1968) and Stollery (1970), is also examined and compared with experimental data reported here. The experiments were conducted in air using a hypersonic gun tunnel under cold wall conditions at M∞ = 12·25. They included measurement of surface pressure, heat-transfer distributions and schlieren studies for concave and convex models.

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Study of heat transfer on concave and convex surfaces of an annular channel with flow swirling

Thermal Engineering ◽

10.1134/s0040601506100132 ◽

2006 ◽

Vol 53 (10) ◽

pp. 833-838 ◽

Cited By ~ 1

Author(s):

E. A. Boltenko

Keyword(s):

Heat Transfer ◽

Annular Channel ◽

Convex Surfaces ◽

Flow Swirling

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Liquid Impingement Flow and Heat Transfer of a Cone Heat Sink With Filet Profiles

Journal of Fluids Engineering ◽

10.1115/1.4046871 ◽

2020 ◽

Vol 142 (8) ◽

Author(s):

Zhiguo Tang ◽

Feng Zhang ◽

Shoucheng Wang ◽

Jianping Cheng

Keyword(s):

Heat Transfer ◽

Nusselt Number ◽

Heat Sink ◽

Pressure Coefficient ◽

Jet Impingement ◽

Reynolds Numbers ◽

Bottom Edge ◽

Convex Surfaces ◽

Flow And Heat Transfer ◽

Heat Transfers

Abstract Jet impingement is a technique for removing heat efficiently. A liquid jet impingement on a cone heat sink was investigated numerically to explore the effect of filet profiles at the top and bottom edge of conical protuberances on fluid flow and heat transfer. An adopted turbulence model was validated through an experiment as described in the literature. Numerical results of pressure coefficient and Nusselt number were obtained for cases with and without filet profiles for variable jet Reynolds numbers and conical angles. Results showed that the flow and heat transfer of conical protuberances with small tip filet profiles are similar to that of the original cone. Pressure coefficient curves are similar to that of convex surfaces, and the average heat transfer slightly increases when the radius of the tip filet profiles exceeds 1 mm. A small filet profile of a conical bottom edge can improve the average Nusselt number. A secondary jet that enhanced the overall heat transfer was demonstrated, and the heat transfers of convex surfaces, as the comparison, with small angles were enhanced in most cases.

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