CFD Modeling of the Effect of the Air- Cooling on Electronic Heat Sources

Abstract

ABSTRACT The target of this research is to study the performance of air cooling of an electronic cabinet including a heat sources (electronic circuit boards) by using axial fan. The cabinet is cooled from the top by one port while the lower and side walls temperature is kept constant. The effect of inlet and outlet air ports positions in the cabinet is considered. In this work, Icepak4.2.8 package is used in the numerical study. The steady of the 3D incompressible viscous flow problem is solved by using the Icepak package. Various air cooling geometries are applied. Specific conditions for each case are defined, and the computational fluid dynamics is provided for three different groups containing six cases of local inlet and outlet ports. The results are performed for cooling effect factor (CEF). KEYWORDS: Air cooling, Electronic circuit, CFD, Icepak. INTRODUCTION he design of cooling systems for electronic equipment is getting very involved and challenging due to an increase in demand for faster and more reliable electronic systems. Therefore, robust and more efficient design and optimization methodologies are required. Natural convection heat transfer is an important phenomenon in engineering systems due to its wide application in electronics cooling, heat exchangers, and double pane windows. Enhancement of heat transfer in these systems is essential from the industrial and energy saving perspectives. The low thermal conductivity of conventional heat transfer fluids, such as water puts a primary limitation on the performance and the compactness of thermal systems. As a result, different cooling technologies have been developed to efficiently remove the heat from these components. The use of a liquid coolant has become attractive due to the higher heat transfer coefficient achieved as compared to air-cooling. Coolants are used in both single phase and two-phase applications. A single phase cooling loop consists of a pump, a heat exchanger (cold plate/mini- or microchannels), and a heat sink (radiator with a fan or a liquid-to-liquid heat exchanger with chilled water cooling). The heat source in the electronics system is attached to the heat exchanger. Liquid coolants are also used in two-phase systems, such as heat pipes, thermo-siphons, sub-cooled boiling, spray cooling, and direct immersion systems for cooling of electronics [1]. The rapid development in the design of electronic packages for modern high-speed computers has led to the demand for new and reliable methods of chip cooling. As stated by Mahalingam and Berg [2], the averaged dissipating heat flux can be up to 25 W/cm² for high-speed electronic components. However, the conventional natural or forced convection cooling methods are only capable of removing small heat fluxes per unit temperature difference, about 0.001 W/cm².