IJSRSET184940 | Received : 08 July 2018 | Accepted : 22 July 2018 | July-August-2018 [ 4 (9) : 198-203] © 2018 IJSRSET | Volume 4 | Issue 9 | Print ISSN: 2395-1990 | Online ISSN : 2394-4099 Themed Section : Engineering and Technology 198 Heat Transfer and Numerical Analysis in Microchannel Heat Exchanger Using Nanofluids : A Review Divyesh Ubale 1 , P. V. Ubale 2 1 M.Tech, Thermal Engineering, Maharashtra, India 2 Associate Professor, GS College, Khamgaon, Maharashtra, India ABSTRACT Nanofluids are gaining lot of importance in thermal applications due to its excellent heat transfer characteristics. Micro-scale heat transfer devices are used on large scale in electronics industry which leads to the development of compact size heat exchanger with high heat transfer coefficient. Recent development in the field of nanotechnology involves the use of suspended nanoparticles in base fluids which leads to the improvement in the heat transfer coefficient of base fluids. This paper summarizes the articles published on enhancement of convective heat transfer in microchannel heat exchanger using nanofluids and effect of various thermophysical properties on heat transfer performance. Theoretical and experimental results for different geometries and effects on Nusselt number are reported in this paper. The results show outstanding increase in the importance of nanofluid application in microchannels. The effects of use of different nanofluids and their performance as compared to base fluids are shown. Keywords: Nanofluids, Microchannel Heat Sink (MCHS), Microchannels, Thermal conductivity, Heat transfer I. INTRODUCTION Conventional heat transfer fluids like oil, water and ethylene glycol are used on a large scale in many industries, including power generation, chemical processes, heating and cooling processes, transportation, microelectronics and other micro- sized applications. The thermal conductivity of heat transfer fluids has great significance in developing equipments with high heat transfer. To improve heat transfer rate, the use of extended-surface (fins and microchannels), the vibration of the surface, suction/injection of fluids and using electrical/magnetic fields has reached to the standstill. Industrial survey indicates the need to develop equipments which are highly compact and leads to increase in heat flux. So development of high efficiency heat transfer fluid is a difficult task. Recently many researchers have attempted to develop special classes of heat transfer fluids so as to increase their heat transfer properties. New method involves the suspension of small solid particles in the base fluid. Different types of solid particles, such as metallic, non-metallic and polymeric can be added into base fluids. However, the earlier studies indicated that the use of suspended particles of millimetre or even micrometre-size leads to high heat transfer enhancement, but some major problems such as poor stability of the suspension, clogging of flow channels, eroding of pipelines and increase in pressure drop in thermal equipments are also experienced [1]. Choi [2] suggested first the term nanofluid in 1995 and it specifies the use of particles of average size of 10 nm for dispersing in base liquids so as to increase thermal conductivity of base fluid and since then this term has gained popularity.