Flow over solid blocks in open ended cavity

S.Z.Shuja1, B.S.Yilbas1, S.M.A.Khan1
1ME Department, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia

Tóm tắt

PurposeThe purpose of this paper is to consider flow over heat generating bodies in an open‐ends cavity, which finds applications in electronics cooling and industrial processing. Heat transfer rates depend on the flow situation in the cavity, which is influenced by the cavity inlet and exit port locations, heat transferring body size and its orientation in the cavity, and the cavity size. Consequently, modeling of flow over heat transferring bodies in an open‐ends cavity and examination of the effect of the aspect ratio and orientation of the heat transferring bodies on the flow field and heat transfer rates becomes essential.Design/methodology/approachThe flow over heat generating solid blocks situated in an open‐ends cavity is considered and the effects of blocks' orientations and aspect ratios on flow field as well as heat transfer rates are examined. A numerical scheme using a control volume approach is introduced to predict flow field in the cavity and heat transfer rates from the blocks.FindingsIt is found that complex flow structure is generated in the cavity due to the aspect ratios and orientations of the blocks. This, in turn, influences significantly heat transfer rates from the blocks in the cavity.Research limitations/implicationsSurface areas of blocks are kept the same and aspect ratio is varied such that the surface area of each block remains the same in the simulations. In addition, Steady flow situation is considered for governing equations of flow and heat transfer in the cavity. However, for the future study transient heating and flow situations can be considered while varying the surface araes of the blocks. This will provide useful information on the circulations in the cavity and the enhancement of heat transfer due to the complex flow structure.Practical implicationsIn practice, cooling effectiveness can be improved through changing the aspects ratio of the heat generating bodies in the cavity.Originality/valueThe findings are original and will be useful for the scientists and the design engineers working the specific area of heat transfer and fluid flow.

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