Heat Transfer Studies in the Flow Over Shallow Cavities

Abstract

Fluid flows along a shallow cavity. A numerical study was conducted to investigate the effects of heating the floor of the cavity. In order to draw a broader perspective, a parametric analysis was carried out, and the influences of the following parameters were investigated: (i) cavity aspect ratio, (ii) turbulence level of the oncoming flow, and (iii) Reynolds number. A finite-difference computer code was used to integrate the incompressible Reynolds-averaged Navier–Stokes equations. The code, recently developed by the authors, is of the pressure-based type, the grid is collocated, and artificial smoothing terms are added to control eventual odd–even decoupling and nonlinear instabilities. The parametric study revealed and helped to clarify many important physical aspects. Among them, the so called “vortexes encapsulation,” a desirable effect, because the capsule works well as a kind of fluidic thermal insulator. Another important point is related to the role played by the turbulent diffusion in the heat transfer mechanism.

A Numerical Assessment of the Air Flow Behaviour in a Conventional Compact Dry Kiln

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A finite volume approach to simulation of polymer melt flow in channels

“…In order to control this problem, artificial dissipation terms are introduced. This procedure was successful to control the problem in the works of Zdanski et al (2004, 2005) and Zdanski and Vaz (2006) dealing with Newtonian and non‐Newtonian flows. In the present paper, the finite volume discretization is adopted whereas finite differences were used in the previous works.…”

Flow and heat transfer over shallow cavities

“…Zdanski et al [9][10][11][12] reported a series of numerical simulations of turbulent flow and heat transfer over 2-D shallow cavities. Regarding the flow structure, their predictions showed that the flow parameters were so sensitive to the variation of cavity aspect ratio, turbulence level of incoming flow, and Reynolds number.…”