Performance, Emission and Pump Wear Analysis of JP-8 Fuel for Military Use on a 558 kW, CIDI Diesel Engine

Investigating the impact of JP-8 fuel on diesel engine performance and emission is very important for military combat vehicles, due to its great potential as alternative fuel under single fuel strategy program for military operation. There is a known torque, horsepower and fuel economy penalty associated with the operation of a diesel engine with JP-8 fuel. On the other hand, a few experimental studies have suggested that JP-8 fuels have the potential for lowering exhaust emissions, especially NOx, CO, HC and smoke opacity compared to diesel fuel. This research evaluates the effect of using JP-8 fuel in a heavy duty diesel engine on performance, emission, and pump wear, and subsequently proposes change to the fuel injection pump calibration to match the designed required operational engine performance with diesel fuel. Experiments were carried out on a 558 kW, B-46-6, supercharged, 12-cylinders, CIDI engine with a hydraulic dynamometer. The results indicate that torque and horsepower of diesel fuel can be matched with fuel economy penalty lower than 4.5%, by increasing the volumetric fuel quantity to compensate the lower density of JP-8 fuel. The lower cetane number of JP-8 fuel caused a slight increase in ignition delay but improved the combustion at load condition, thus lowering the combustion noise. Emissions such as CO, HC, NOx, and smoke opacity were measured on engine maximum operating speed of 2000 rpm at 100% load condition, whereas volumetric fuel consumption was measured between 1200-2000 engine rpm under load conditions. The fuel pump wear was tested after 100 hours run.