IJSRSET17323 | 01 March 2017 | Accepted: 08 March 2017 | March-April-2017 [(2)2: 34-38] © 2017 IJSRSET | Volume 3 | Issue 2 | Print ISSN: 2395-1990 | Online ISSN : 2394-4099 Themed Section: Engineering and Technology 34 Enhancement of Natural Convection Heat Transfer from Horizontal Rectangular FIN Arrays : A Review N. P. Salunke 1 , I. N. Wankhede 2 , P. L. Sarode 3 1 H.O.D, Mechanical Department, RCPIT Shirpur, Maharashtra, India 2 PG Student, Mechanical Department, RCPIT Shirpur, Maharashtra, India 3 Assistant Professor, Mechanical Department, RCPIT Shirpur, Maharashtra, India ABSTRACT In this study, various fin geometries are referred for steady-state natural convection heat transfer. The effects of fin spacing, fin length, fin height, % of perforations, shape of perforations etc. are studied. For high powered street LED lights heat sinks with horizontal fin arrays are utilized. Large amount of heat generated in these street LED‟s must have to be dissipated effectively, so that the life span of the same can be enhanced. For the heat sinks currently utilized in the high powered street LED‟s a stagnation zone is formed at the symmetry centre of the fins this causes the problem in air circulation ultimately affects the heat dissipation capacity of the heat sink. Therefore there should be the proper provision for air to be drawn. Keywords: Perforation, Fins, Steady state, Natural convection I. INTRODUCTION High–power LED is a promising technology for future lighting application since it can save energy and has a long life time. To obtain more lumen, the powerful electric current of LED chips grows fastly nowadays. However, as to the high power LED chips, generally nearly 80% of the input power is transformed into heat while the rest is converted into light, and this will lead to a series of penalties [1].Therefore, to gain a dependable and perfect product with good enactment, thermal management of high power LEDs is very important. To solve the LED heat dissipation, some methods can be taken, such as improving in chip luminous efficiency, which will drastically reduce the heat generation, improving in the package, which will reduce the inner thermal resistance, or improving in the heat transfer coefficient of heatsink, such as micro jet cooling system, heat pipe [2], etc. But these techniques are rarely put into use because of reasons including cost factors, high reliability and maintenance requirements. The life of LED lamp is usually about 100,000 hours, and it works in the outdoor environment. Therefore, the heat sink of high-power LED is usually cooled through the natural convection as shown in fig. Figure 1. The heat sink of LED street lamp The thermal management of LEDs for general illumination applications is of primary importance to their dependability and efficiency. In considering the thermal management of high power LED‟s, two main encounters must be considered. First, while a single device consumes relatively low power, large heat fluxes exist at the die level, of the order of 300W/cm2 or greater. Such high heat fluxes frequently require exceptional heat spreaders at the die level in order to help disintegrate such concentrated heat loads. Second, since the luminous output of an individual high power LED is insufficient to replace a traditional light source, multiple LED‟s are necessary for general radiance. With the use of large LED arrays, it is possible to generate