International Journal of Research & Review (www.ijrrjournal.com) 448 Vol.6; Issue: 7; July 2019 International Journal of Research and Review www.ijrrjournal.com E-ISSN: 2349-9788; P-ISSN: 2454-2237 Research Paper Effect of Fuel Physical Properties on Spray Parameters of Residual Fuel Oil (RFO) Martins. B. Ogunedo 1 , Kelvin C. Nduaguba 2 1 Department of Mechanical Engineering, Imo State University, Owerri. 2 Department of Mechanical Engineering, NnamdiAzikiwe University Awka, Anambra. Corresponding Author: Martins. B. Ogunedo ABSTRACT This paper studied the effect of fuel physical properties on spray parameters of RFO. To achieve this, the fuel (RFO) was characterized to determine its physico-chemical properties, and an experimental set up was designed to visualize and capture the spray pattern of the fuel. After which images obtained were processed and analysed using Image J software to determine the spray length, spray cone angle, spray area, spray volume, and spray velocity values of the fuel. Results obtained showed that the viscosity of RFO decreases with increase in temperature. It was also seen that the high viscosity and surface tension of RFO accounts for the higher spray parameters values of 456 mm for spray length, 22.67° for spray cone angle, and 2.85 mm for SMD at a viscosity of 9.16 mPa.s. This condition, will lead to a higher spray volume causing the engine to run on a rich mixture after initial start-up conditions. This leads to challenges such as reduction in power and clogging of injector nozzle tip due to increase in carbon deposit. Keywords: Viscosity, Density, Surface Tension, Spray length, Spray Area, Spray volume, Spray cone angle, Sauter mean diameter. INTRODUCTION Issues arising due to the instability of electric power in Nigeria have forced Small and Medium scale Enterprise (SME) to generate their own power in order to make their businesses thrive. This electric power is generated through the use of standalone power plants such as the gas, petrol and diesel powered generating set. The diesel powered electric generating set is more dominant because of its advantages of lower running and capital cost, ease of installation, simple plant layout, and ability to carry heavy electrical load. However, the high cost of diesel which translates to a high product cost makes it very difficult for these SMEs to maintain/attain influence in a competitive global market. To mitigate this challenge, the resort to surrogate fuels such as RFO which helps cut down production cost. This action comes with attendant consequence of deposit formation in nozzle tip, inability of the generating set to re-start after shutdown, and subsequent deterioration of injector nozzle/failure of injector nozzle. It then becomes imperative to identify factors which contribute to the spray behaviour of RFO when used as a surrogate fuel in diesel engine. Hence, this study is aimed at investigating the effect of fuel physical properties on the spray parameters of RFO. Research Elaborations Spray parameters are categorized as Macroscopic and Microscopic spray parameters. Macroscopic spray parameters indicate the relationship between the spray