Orientation effects on natural convection heat dissipation of rectangular fin heat sinks mounted on LEDs

Experimental and numerical study on the heat sink with radial fins and a concentric ring subject to natural convection

“…The Nusselt number is shown to increase as the fin number increases for fixed Elenbaas number. This is coincident with literatures[12,19], and is due to the fact that the Elenbaas number is proportional to fourth power of the fin It should be noted that, even though the Nusselt number decreases with decreasing fin number, the heat transfer coefficient increases with decreasing due to the retardation of boundary layer overlapping. The effect of the orientation with fin length on the Nusselt number is also presented clearly.…”

Design of passive coolers for light-emitting diode lamps using topology optimisation

“…: Yu et al [2] investigate various fin configurations for radial heat sinks; Jang et al [3] perform multidisciplinary optimisation of pin-fin radial heat sinks and found that the pin-fin configuration lead to more uniform cooling performance due to repeated leading-edge effects; Jang et al [4] examine pinfin radial heat sinks with different fin-height profiles and conclude that the fin height should be largest at the circumference and decrease towards the centre. The effect of orientation is less well investigated, but strong examples are: Jang et al [5] show that the orientation effect for a cylindrical radial straightfin heat sink is strong and find drag and convection efficiency to be inversely correlated; Shen et al [6] investigate the orientation effect for rectangular straight-fin heat sinks and conclude that denser heat sinks are more sensitive to orientation; Li et al [7] examine the effect of adding an outer chimney-rim to radial heat sinks, as well as the orientation effect on thermal performance, and concluded that a chimney can increase thermal performance by up to 20%.…”

Thermal Performance of Fined Plate Mini-Channel Heat Sink

“…Yi Li et al [5] assessed the performance of plate-fin heat sinks in a cross flow. Shen et al [6] carried out experimental and numerical study of the orientation effects on the fluid flow and heat transfer of rectangular fin heat sinks under natural convection conditions. Jang et al [7] examined the orientation effect for a cylindrical heat sink used to cool an LED light bulb numerically.…”