Complete heat balance, performance, and emission evaluation of a CI engine fueled with Mesua ferrea methyl and ethyl ester’s blends with petrodiesel Neetu Singh 1,2 • Himansh Kumar 1 • M. K. Jha 2 • Anil Kumar Sarma 1 Received: 26 February 2015 / Accepted: 9 May 2015 Ó Akade ´miai Kiado ´, Budapest, Hungary 2015 Abstract In this investigation, blends of Mesua ferrea methyl esters (FAME) and ethyl esters (FAEE) with pet- roleum diesel were used for complete thermal analysis (heat balance) in a computerized compression ignition engine at variable load and at different compression ratios (CR 15 and CR 18). In addition to heat balance, perfor- mance parameters like brake thermal efficiency and brake- specific fuel consumption of the CI engine fueled with biodiesel and blends were also investigated. The emissions analysis viz. CO, CO 2 , HC, NOx, and O 2 were measured using an AVL DiGas 444 analyzer. It was observed that the work done was increasing with the increase in load and to some extent with the increase in CR and blending ratio. At CR 18, FAEE-B10 showed the maximum 29.3 % useful work, while diesel showed only 26.3 % at full load con- dition. At highest load and CR 18, HC, NOx, and CO 2 emissions were found to be lesser than that from the pet- roleum diesel, and among all the blends, FAEE-B10 was found as a better substitute for diesel engine. Keywords Mesua ferrea L. oil  Fatty acid methyl ester  Fatty acid ethyl ester  Variable load  Heat balance  Efficiency and emission Abbreviations BP Brake power BSFC Brake-specific fuel consumption BTHE Brake thermal efficiency CO 2 Carbon dioxide CO Carbon monoxide CR Compression ratio EE-B10 Ethyl ester B10 blend EE-B20 Ethyl ester B20 blend FAEE Fatty acid ethyl ester FAME Fatty acid methyl ester GHG Green house gas HC Hydrocarbon ME-B10 Methyl ester B10 blend ME-B20 Methyl ester B20 blend VCR Variable compression ratio List of symbols CV Calorific value (MJ kg -1 ) C Pg Specific heat of gas (kJ kg -1 K -1 ) C PW Specific heat of water (kJ kg -1 K -1 ) m a Air flow rate (kg h -1 ) m f Fuel flow rate (kg h -1 ) m w Engine water flow (kg h -1 ) T 1 Engine water inlet temperature (K) T 2 Engine water outlet temperature (K) T 3 Exhaust gas to calorimeter inlet temperature (K) T 4 Exhaust gas to calorimeter outlet temperature (K) Introduction Biofuels, especially biodiesel in recent times, are pulling in popularity due to multiple causes such as escalating prices of petroleum fuels and detrimental environmental concerns Electronic supplementary material The online version of this article (doi:10.1007/s10973-015-4777-8) contains supplementary material, which is available to authorized users. & Anil Kumar Sarma draksarma@gmail.com; anil_tu@yahoo.co.in 1 Chemical Conversion Division, Sardar Swaran Singh National Institute of Renewable Energy, 12-KM Stone, Jalandhar Kapurthala Road, Kapurthala, India 2 Department of Chemical Engineering, Dr. B R Ambedkar National Institute of Technology, Jalandhar, India 123 J Therm Anal Calorim DOI 10.1007/s10973-015-4777-8