Investigation of the effect of air intake pressure and fuel injection parameters on upgrading power and emissions of heavy duty diesel engine

In this paper, the effect of fuel injection and intake systems on upgrading the power of RK215 HD diesel engine investigated. The process simulated in four state with full load performance by AVL-Fire V8.3.1 software.
The first state is about the original engine with semi-triangular discharge curve, 139mg fuel injection per cycle, nozzle diameter of 3mm and air intake pressure of 4.2bar. In the second state the effect of changing the discharge curve to rectangular type and reducing the nozzle diameter and increasing fuel injection quantity is investigated which is resulted in 0.2, 21, 16.6 and 27 percent increase in peak pressure, output power, NO and soot emissions, respectively. In the third state, only the effect of air intake pressure increase (5bar) with respect to the second state is considered. In this state the amount of peak pressure, output power and NO emission is increased by 15.3, 26, 9 percent, respectively and soot emission reduced by 4.6%. In the fourth state the nozzle diameter is reduced with respect to the third state. The result is 10.4 and 24 percent increase in peak pressure and output power, respectively. In the other hand, the Soot and NO emissions are decreased about 22 and 4.6 percent, respectively.