Asix cylinder four stroke high speed direct injection diesel engine is operating at 2400 rpm. the engine total displacement is 3.6 liter. under this condition, the equivalence ratio is 0.5 and the volumetric efficiency is 2.0 with turbocharging. each cylinder has one injector and each injector has 6 nozzle holes. the discharge coefficient of the injector nozzle is 0.75. the injection pressure difference across the nozzle is 100 mpa. fuel density is 800 kg/m3, and stoichoimetric air-fuel ratio of the fuel is 14.5.
a). what will be the injected fuel mass for one cylinder during one cycle? [4.88x10-5 kg/(cyl-cycle)]
b). if the fuel injection with the fuel mass in a) is completed in 15 crank angle degrees, what will be the nozzle hole diameter for the injector? [0.182 mm]
c). if the fuel injector nozzle holes in part b) are further polished with the nozzle discharge coefficient increased to 0.80 and the injection pressure is increased to 160mpa, what will be the injection crank angle degrees if other parameters keep the same under this operating condition? [11.13 degree]