The intention of the prevailing effort is in the direction of experimentally look for the combined outcome of compression ratio and a number of nozzle holes on performance and emissions of a compression ignition engine by means of an emulsion fuel obtained from aegle marmelos (Bael) oil. This exertion consists of the exergy examination of compression ignition engine towards maximizing the work availability and decreasing the destroyed availability. Ternary blends of diesel - aegle marmelos-diethyl ether (DEE) within the proportion as percentages 100:0:0 (D), 70:20:10 (B1), 60:30:10 (B2), 50:40:10 (B3) became tested in a variable compression ratio (VCR) engine. When operating the diesel engine with B2, Brake thermal efficiency (BTE) of the engine is better by 4.3%, nitric oxides (NOx) emission has been reduced 3.9% at 100% load in compression ratio (CR) 17.5 with number of nozzle hole (NH) 5. The exergy efficiency of B2 fuel has been found 63.88% of fuel input at CR17.5 with 100% engine load. Increasing the number of nozzle holes improves the performance of the diesel engine fueled with bael blends in terms of reduced brake specific energy consumption (BSEC), increased BTE and reduced emissions like hydrocarbon (HC), carbon monoxide (CO) and smoke. (C) 2017 Elsevier Ltd. All rights reserved.