Asian Journal of Applied Sciences (ISSN: 2321 – 0893) Volume 06 – Issue 06, December 2018 -Asian Online Journals (www.ajouronline.com) 591 An Effect of Biosolar-Water Emulsion on Small Marine Diesel Engine Beny Cahyono * , Taufik Fajar Nugroho, Tony Bambang Musriyadi Sepuluh Nopember Institute of Technology (ITS) Indonesia * Corresponding author’s email: cak_beny [AT] yahoo.com ____________________________________________________________________________________________________________ ABSTRACT---- This study aims to analyze the effect of water/biosolar emulsion fuel on the performance of engine diesel used in small capacity diesel engines. The fuel used is a mixture of biosolar 20% which is added 10% and 15% water (b20,WDE 10%, WDE 15%) which will be compared with dexlite fuel and biodiesel 20% (b20). Measurement of engine performance with various fuels was carried out in accordance with IMO marine engine regulation tier 3. The water-emulsified diesel could be used in the light-duty small diesel engine without modifications. The result shows that the net diesel fuel consumption and the exhaust gas temperature decreased with increasing water content of fuels over the investigated loading range. Performance produced by DWE 10% and 15% will been reduce Power, and Torque at each RPM. In detail, DWE 10% has better results than the DWE 15%. In the NOx emission test results, the use of water/biodiesel emulsified fuels 10% and 15% can reduce NOx emissions. Keywords— biodiesel, B20, water/biosolar emulsion 10%, water/biosolar emulsion 15%, engine performance _________________________________________________________________________________________________ 1. INTRODUCTION The use of biodiesel fuel is expected to contribute to the reduction of global warming, M. Lapuerta, O. Armas, J. Rodríguez- Fernández [2003]. Also, using a blend of biodiesel fuel as an alternative to pure fossil fuels has a number of other advantages: it is less polluting, cost effective, it has higher lubricity and a higher flash point, and it can be used in Diesel engines with minimal, or no, modifications, M. Lapuerta, J. Rodríguez-Fernández, O. Armas [2003], L.C. Meher, D. Vidya Sagar, S.N. Naik [2006], R.O. Dunn [2009], J. Hill, E. Nelson, D. Tilman, S. Polasky, D.Tiffany [2006], J. Tickell, K. Roman [2003]. According to the U.S. Environmental Protection Agency Tier I and Tier II standards (see US Environmental Protection Agency [2014] for details), fatty acid methyl ester (FAME) biodiesel types produced over the last decade pass the testing requirements for health effects. The use of water–diesel emulsions has been around since 1970’s, A. Lif, K. Holmberg [2006] and some researchers have also reported that the use of a small amount of water in the biodiesel blends induces a trade-off between reductions of PM, CO and also reduction in NOx contrary to using straight biodiesel that lead to increased NOx emissions, S.-H. Liu, Y.-C. Lin, K.-H. Hsu [2012], Y.C. Chang, W.J. Lee, H.H. Yang, L.C. Wang, J.H. Lu, Y.I. Tsai, et al. [2014], Y.-C. Chang, W.- J. Lee, S.-L. Lin, L.-C [2013]. According to Alahmer [2013], the presence of small amounts of water in the fuel has a significant effect on the physical and chemical kinetics of combustion, where by it reduces combustion temperatures and providing OH radicals in the combustion environment. The OH radicals act to control NOx formation and to oxidize soot resulting in reducing both NOx and PM emissions. In addition, the micro-explosion action of water droplets has been proposed as the major mechanism that results in a better turbulence of fuel and oxidants, causing more complete combustion and consequently a significant reduction of criteria pollutants emissions, when using water-containing fuels. Frequently, surfactants are added in the emulsions to stabilize the water–diesel mixtures in order to minimize the coalescence mechanism of the water phase as well as reducing the surface tension between the diesel and water phases, M. Huo, S. Lin, H. Liu, C.-f.F. Lee [2014]. In a study of stability of water diesel emulsions, Ghannam and Selim [2009] determined that: (a) surfactants are essential for stability of water –diesel emulsions (b) the stability of water–diesel emulsions decreased with an increase in water fractions (c) at higher fractions of water, more surfactants should be employed as well as higher mixing rates (d) the density of water–diesel emulsions increase with increase in water fractions. As mentioned earlier water addition is one of the techniques of emission control in the diesel engine. Different ways can be used to introduce water into the engine and they include (i) mixing water in form of steam with air at inlet, (ii) injecting water and diesel coincidentally (iii) forming water and diesel emulsions which can be stabilized or not be stabilized with surfactants or co-solvents such as natural organic enzymes, W. Yuan, A.C. Hansen, Q. Zhang [2003]. A comparison of water–diesel emulsion and timed injection of water into the intake manifold of a diesel engine was done by Subramanian [2011] and the performance in controlling NOx and smoke emissions was evaluated. The emulsion method was more