Abstract—Electronic systems cooling is an attractive research area in engineering. The aim of this research is to design vortex promoters for cooling of electronic equipment. Different shapes of vortex promoters are used in the experimental study for turbulent flow and the results are used to validate the results of a previous computational work performed by the authors. Another aim is to choose an appropriate promoter and promoter location which provides best turbulence effects and most effective cooling. Temperature values are measured with thermocouples at several monitoring locations. The results show that the most effective vortex promoter for cooling is triangular type of promoter for the flow conditions tested. Index Terms—Electronic cooling, experimental study, turbulent flow, vortex promoter. I. INTRODUCTION Electronic systems’ cooling has been extensively examined recently because of the interest from both scientific and technological points of view. On the technological part, with the improvements of the electronics systems, higher processing speeds, more power, smaller systems become more of a necessity than ever before. One of the most important results of these necessities is the need to handle more complex geometries. Therefore one of the biggest issues in the electronics systems is the cooling of these complex geometries. Especially in military, healthcare and aerospace applications, effective cooling is crucial. With an efficient cooling, electronics systems become more reliable and durable [1]. On the scientific part, heat that is generated in electronic systems is proportional to the square of voltage and the frequency of the system. So, engineers try to increase the frequency and decrease the voltage to be able to decrease heat generation. Developing effective cooling techniques of electronic systems is a major challenge. Therefore different cooling techniques have been developed to remove the heat from electronic components [2]-[4]. Two main types of cooling are air and liquid cooling [2], [5], [6]. Air cooling is an inexpensive but reliable way of cooling. It is easy to find air; design and maintenance are also easy with air. Therefore, air cooling is used widely in electronic systems cooling. Heat transfer can occur in three different ways: conduction, convection and radiation. Convection is a widely used cooling technique. Forced Manuscript received October 31, 2012; revised February 17, 2013. E. Ayli, C. Turk, and S. Aradag are with the TOBB University of Economics and Technology, Ankara, 06560, Turkey (e-mail: ueayli@etu.edu.tr; cturk@etu.edu.tr; saradag@etu.edu.tr). convection is a better choice when it is compared with natural convection as it provides higher heat transfer rates and higher Prandtl numbers. In forced convection, adding a fan to the system is one of the methods. Air is forced to move with the help of a fan. To decrease system temperature, fan speed, which is one of the important parameters in efficient cooling, should satisfy turbulent flow conditions [1], [7]. Aradag et al. [7] used vortex promoters for effective cooling. They performed their computational analyses in two parts. In the first part, heat convection coefficients and maximum temperatures are obtained in a single circuit system for laminar flow. In the second part of the study, the effects of the distance between two heat sources are examined. Two different types of vortex promoters are utilized to decrease maximum temperature values in the system. When the results are examined, it is seen that the systems that include vortex promoters, regardless of the geometry and the location of the promoters, have smaller maximum temperature when compared with the case without a vortex promoter. Triangular vortex promoters are shown to be able to decrease maximum temperatures in the system more than rectangular promoters. Their study emphasizes with the help of CFD results that the heat sources should be placed as far away from each other as possible. In the study of Etemoglu et al [8], some possible solutions are given to decrease heat generation in electronics systems. According to their study, increasing the frequency and decreasing the voltage can decrease heat generation. Adding a fan to the systems for cooler air is another possible solution which is provided in this article. Heat transfer rates are increased in forced convection. Spreading heat with a copper sheet to achieve turbulent flow is also suggested to decrease the temperature of the system. Gomes [1], analyzed the effects of the size, shape of the promoter and the location of heat sources on cooling, experimentally. According to this study, as shaped corners provide stronger vortices, hexagon promoter is the most effective promoter which creates the biggest disturbance in the flow. Second effective promoter geometry is the square one. Circle promoter has no cooling effect in the system. Better heat transfer occurs when separation between the heat sources are farther. Icoz and Jaluria [9] investigated natural convection heat transfer in a horizontal channel with two heat sources. Most appropriate boundary conditions to accurately model the transport processes are investigated. The effect of Grashof number, cavity dimensions, distance between the heat sources, heat transfer characteristics and their effects on the flow are also investigated. When the channel height and the separation distance are increased, instability is observed. Experimental Investigation of Cooling of Electronic Equipment Ece Ayli, Caner Turk, and Selin Aradag 153 DOI: 10.7763/IJMMM.2013.V1.33 International Journal of Materials, Mechanics and Manufacturing, Vol. 1, No. 2, May 2013