Study On Waste Heat Recovery In An Internal Combustion Engine C. Bibin, P. Seenikannan, N. Kanthavelkumaran Assistant Professor, Dept. of Mechanical Engg., The Rajaas Engineering College, Vadakkangulam. Prof & Head, Dept. of Mech. Engg., Sethu Institute of Technology, Pullor, Tamilnadu Associate Professor, Mech. Engg., Arunachala College of Engineering for Women, Manavilai, Vellichantai, KK Dist, India Abstract Usually Internal Combustion engine an extensive heat is passed away by exhaust gases. To recover the waste heat, a variety of methods are being adopted. Turbo charging is the one of the best method to recover the waste heat. Throughout this task an attempt has been made to look at the various possibilities of waste heat (energy) recovery methods in conventional commercial two wheeler and four wheelers. In this circumstance, a new theory of hybrid engine has also been discussed. Different methodologies were implemented to recover the waste heat from IC engines. Basically, by introducing a supplementary combustion chamber and injecting an additional proper fuel and then allowing it to increase in a turbine which forms the part of turbo charger unit. Thus the waste heat energy is utilized to burn an additional amount of fuel. The subsequent stage contains a thermoelectric generator which produces electrical energy by utilizing the high heat of exhaust gases. The final stage energy recovery is done by combination of compressor and an alternator. Both being coupled to the turbine shaft, produces electrical energy and compressed air which can be accumulate and used effectively for running any auto auxiliaries. Thus the principle of electro turbo generation has been adopted for waste heat recovery. In order to use the abovementioned combination of waste heat recovery systems a matrix has also been suggested. Keywords: waste heat recovery, spark ignition, internal combustion engine, engine exhaust 1. Introduction National energy security, rising energy prices, increasingly aggressive global markets, and stringent regulations for environmental emissions are the primary driving forces in the search for sustainable and economically viable technologies that incorporate efficient and clean approaches to energy conversion and utilization. Internal combustion (IC) engines are the prime movers of choice when high power densities and efficiencies are desirable. Because of relatively cheap fuel prices in the last few decades, IC engines had been optimized for high power densities and low emissions. However, in recent years, with escalating fuel prices and concerns about sustainability, engine efficiency has assumed greater importance. Since the oil resources are depleting day by day with a rapid increase demand for energy, research is in progress to identify an alternative source. At the same time the present day equipments are being developed to give maximum output to conserve resources till an alternative is developed. Reciprocating internal combustion engines being the most widely preferred prime movers gives a maximum efficiency range of 27% to 29%. Rotary engines, even though having higher efficiencies up to 45% are restricted to aircrafts due to their very high speeds of 45000 rpm to 90000 rpm. Cogeneration is the method of simultaneous production of heat and other form of energy in a process. Many cogeneration techniques have been employed in IC engines to recover the waste heat. Turbo charging is also a kind of waste heat recovery technique in which the exhaust gases leaving the engine are utilized to run a turbine to produce power. Reciprocating engines remain the dominant power plant for both vehicles and power generation up to a few MW. Yet, circa 30% of the energy in the fuel is lost through the exhaust system. In today's market, it has become essential to attempt to recover some of this “wasted energy” and put it to good use. Exhaust Heat Recovery (EHR) systems are playing an increasingly important role in the Emissions and Fuel Consumption challenges facing today's Heavy Commercial Vehicle (HCV), Off-Highway and Power Gen markets globally. Exhaust heat recovery using electro turbo generators by Patterson, A., Tett, R., and McGuire, J. puts forward an argument in favor of Electro-Turbo compounding as a system that is technically mature enough to benefit the above markets today. Only a part of the energy released from the fuel during combustion is converted to useful work in an engine. The remaining energy is wasted and the exhaust stream is a dominant source of the overall wasted energy. There is renewed interest in the conversion of this energy to increase the fuel efficiency of vehicles. There are several ways this can be accomplished. This work involves the utilization thermoelectric (TE) materials which have the capability to convert heat directly into electricity. A new model was developed to study the feasibility of the impression. Waste energy recovery identification is newly developed from design of Experiment was performed to improve the design on the basis of higher power generation and less TE mass, International Journal of Engineering Research & Technology (IJERT) Vol. 1 Issue 10, December- 2012 ISSN: 2278-0181 1 www.ijert.org