Rohan R. Ozarkar et al./ Elixir Mech. Engg. 80 (2015) 31045-31048 31045 Introduction Alcohol fuels particularly ethanol can be produced by fermentation of bio mass crops, mainly sugar cane, wheat and wood. Usage of alcohols and liquefied petroleum gas as a fuel for spark ignition engines has some advantage to compare the gasoline. The engine thermal efficiency can be improved with increasing of compression ratio. Alcohols burns with lower flame temperatures and luminosity owing to decreasing the peak temperature inside the cylinder and hence the heat losses and NOx emissions are lower. The world is presently confronted with crises of fossil fuel depletion [1]. Ethanol, a promising fuel Among the various alcohols, ethanol is known as the most suited fuel for spark ignition (SI) engine. The most attractive properties of ethanol as an SI engine fuel are that it can be produced from renewable energy sources such as agricultural feedback and it has high octane number and flame speed. Production method and properties of ethanol will be further explained and discussed in the following sections. Ethanol can be used in SI engines as pure or by blending with gasoline. Pure ethanol necessitates some modification on engine design and fuel system whereas it can be used in SI engines by blending with gasoline at low concentration without any modification. It was reported that using gasoline-ethanol blends including ethanol at low concentration could improve engine performance and exhaust emission [2, 3]. VCR Engine The concept of variable compression ratio (VCR) promises improved engine performance, efficiency and temperatures. During the early part of combustion a small residual gas fraction owing to higher compression ratio gives faster laminar flame speed. Therefore, the ignition delay period is shorter. As a result, at low loads, the greater the compression ratio, the shorter is the combustion time. The time loss is subsequently reduced. Therefore, it seems reasonable that fuel consumption rate is lower with high compression ratios at part load. The main feature of the VCR engine is to operate at different compression ratios, depending on the vehicle performance needs. A VCR engine can continuously vary the compression ratio by changing the combustion chamber volume. Up to 20% to 30% exhaust emission are reduced; also the fuel economy is increase [1]. Fuel Properties And Experimentation For blending 99.99% pure ethanol which is produced by ‘Analytical CS Reagent’ and gasoline are used. Preparation of Blend For the presented work the different blends of gasoline and ethanol are used. They are E0, E5, E10 and E15 the number following E indicates percentage of volumetric amount of ethanol in gasoline. These blends are prepared for two liters of each category. The ethanol used for blend preparation is 99.9% pure and the properties are given by the supplier in the test report provided. Figure 1. Blend Preparation Properties of Blends The properties of blended fuels are determined at the beginning of the experiment. Table 1: Gasoline and Ethanol Properties [4] If the properties of the pure gasoline and ethanol are known, the properties of the blended fuels are calculated as follows: Effects of various ethanol blends in gasoline on variable compression ratio engine Rohan R. Ozarkar, Nitin G. Shinde and Manish S. Sathe Department of Mechanical Engineering, SES’s RCPIT, Shirpur (MH) India. ABSTRACT The objective is to determine blend which gives less emission and good performance characteristics, comparing emissions and performance characteristics between blends and pure gasoline fuel at different speeds, different compression ratios and different loads and carry out the test on VCR engine at full throttle valve opening without modification and without knocking at, different gasoline-ethanol blends (E5,E10,E15) and pure gasoline, different compression ratios (8,9,10) and different speeds (1600,1700,1800 in rpm) where, performance characteristics are volumetric efficiency, brake power, brake thermal efficiency and emissions of CO, CO 2 , HC. © 2015 Elixir All rights reserved ARTICLE INFO Article history: Received: 16 January 2015; Received in revised form: 28 February 2015; Accepted: 10 March 2015; Keywords Ethanol Blends, Gasoline, Compression Ratio, Emission. Elixir Mech. Engg. 80 (2015) 31045-31048 Mechanical Engineering Available online at www.elixirpublishers.com (Elixir International Journal) Tele: E-mail addresses: ngshinde23@gmail.com © 2015 Elixir All rights reserved