Numerical investigation of natural convection from inclined plate finned heat sinks

Mehrtash, Mehdi
Finned heat sink use for electronics cooling via natural convection is numerically investigated. An experimental study from the literature that is for vertical surfaces is taken as the base case and the experimental setup is numerically modeled using commercial CFD software. The flow and temperature fields are resolved. A scale analysis is applied to produce an order-of-magnitude estimate for maximum convection heat transfer corresponding to the optimum fin spacing. By showing a good agreement of the results with the experimental data, the model is verified. Then the model is used for heat transfer from inclined surfaces. After a large number of simulations for various forward and backward angles between 0-90 degrees, the dependence of heat transfer to the angle and Rayleigh number is investigated. It is observed that the contributions of radiation and natural convection changes with the angle considerably. Results are also verified by comparing them with experimental results available in literature.


Characterization of spray cooling for electronic devices
Öksüz, Selçuk; Çetinkaya, Tahsin Ali; Department of Mechanical Engineering (2014)
The trends in electronics industry are towards miniaturizing and increasing power needs that result in high heat fluxes. High heat fluxes lead to thermal problems and performance loss in devices. Well known cooling techniques, such as utilization of fans or single phase liquid cooling, have limited cooling capacity. Among two phase cooling methods, spray cooling is one of the best cooling technique. Thus, in this study it is aimed to construct a compact and high performance yet simple experimental setup for...
Implementation of metal-based microchannel heat exchangers in a microrefrigeration cycle, and numerical and experimental investigation of surface roughness effects on flow boiling
Jafari Khousheh Mehr, Rahim; Okutucu Özyurt, Hanife Tuba; Ünver, Hakkı Özgür; Department of Mechanical Engineering (2015)
A microscale vapor compression refrigeration cycle has been constructed for possible application in the thermal management of compact electronic components. The micro-evaporator and micro-condenser components have been fabricated using wire electron discharge machining and micromilling, respectively. Three microevaporators have been manufactured with different surface roughness for the experimental and numerical investigation of roughness effect on nucleate flow boiling in microchannels. In the numerical pa...
Numerical Investigation of Various Approaches to Avoid Natural Convection Instabilities Inside the Channels of Horizontal Plate Fin Heat Sinks
Tarı, İlker (2016-11-17)
In case of natural heat convection from a horizontal plate fin heat sink, heat transfer rates highly depend on the geometric parameters. It is observed that if the fin height is very low, fresh cooler air may not be able to reach middle parts of the heat sink causing an ineffective use of the extended heat transfer area. Using a validated numerical model of an underperforming heat sink, various ways of improving heat sink geometry has been investigated. The tried approaches include leaving gaps in the lengt...
Multi-dimensional modelling of evaporation in the micro region of a micro grooved heat pipe
Akkuş, Yiğit; Dursunkaya, Zafer; Tarman, Işık Hakan; Department of Mechanical Engineering (2015)
Capillary cooling devices are preferred in heat removal from electronic components which are characterized by high heat dissipation rates. Heat pipes use various wick structures to generate the necessary capillary action. Heat pipes that use grooved micro-channels as wick structures, have been widely studied by researchers due to the fact that their simple geometry enables the modelling of fluid flow and heat transfer both analytically and numerically. Near the attachment point of liquid-vapor free surface ...
Design, optimization and testing of micro-evaporator and micro-condenser components used in a miniature vapor compression refrigeration cycle
Türkakar, Göker; Okutucu Özyurt, Hanife Tuba; Department of Mechanical Engineering (2016)
This study aims to optimize the dimensions and operating conditions of two main components of a miniature vapor compression refrigeration cycle (MVCRC), evaporator and condenser by using entropy generation minimization (EGM). In addition, some performance tests are conducted on a MVCRC which is constructed based on the EGM analysis as long as the manufacturing constraints permit. R134a is used as the coolant. Entropy generation rate in the evaporator of the MVCRC is investigated under the effects of exit va...
Citation Formats
M. Mehrtash, “Numerical investigation of natural convection from inclined plate finned heat sinks,” M.S. - Master of Science, Middle East Technical University, 2011.