Improving flow structure and natural convection within fin spacings of plate fin heat sinks

Özet, Mehmet Erdem
The main objectives of this thesis are to numerically investigate the previously observed recirculation zones and longitudinal vortices that occur in low fin height plate finned horizontal heat sinks and to improve the flow structures and heat transfer in these zones using various approaches with the help of simulations performed using commercially available CFD software. The approaches used for improvements are replacing the outer most fins with higher ones, introducing gaps on the length of the fins in various patterns, and introducing interstitial fins of different shapes within the channels among the plate fins. Starting with a validated model of the original low height plate fin heat sink and making the geometric modifications without altering the solution strategy, newer models that do not require experimental validation are obtained. The original model and the newer models are used in a series of simulations with related parametric analyses. The performances of the newly introduced heat sink geometries are compared with the performance of the original low height plate fin heat sink using the simulation results. Among these alternatives the one performing the best is selected as an optimal solution to the recirculating flow problem observed in the low height plate fins.


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Citation Formats
M. E. Özet, “Improving flow structure and natural convection within fin spacings of plate fin heat sinks,” M.S. - Master of Science, Middle East Technical University, 2015.