TY - JOUR TI - Studies on a CI engine using orange skin powder diesel solution with different fuel nozzle opening pressure AU - Purushothaman Krishnan AU - Nagarajan Govindan JN - Thermal Science PY - 2009 VL - 13 IS - 3 SP - 103 EP - 112 PT - Article AB - Experiments have been conducted to study the effect of nozzle opening pressure on the combustion process and exhaust emissions of a direct injection diesel engine fueled with orange skin powder diesel solution (OSPDS). Earlier investigation by the authors revealed that 30% OSPDS was optimum for better performance and reduced emissions. In the present investigation the nozzle opening pressure was varied with 30% OSPDS and the combustion, performance, and emissions characteristics were studied and compared with those of diesel fuel. The different nozzle opening pressures studied were 215 bar, 235 bar, and 255 bar. The results showed that the cylinder pressure with 30% OSPDS at 235 bar fuel nozzle opening pressure, was higher than that of diesel fuel as well as at other nozzle opening pressures. Similarly, the ignition delay was longer with shorter combustion duration in case of 30% OSPDS at 235 bar nozzle opening pressure. The brake thermal efficiency was higher at 235 bar than that of other fuel nozzle opening pressures with OSPDS and lower than that of diesel fuel. The NOx emission was higher and HC and CO emissions were lower with 30% OSPDS at 235 bar. The smoke emission was marginally lower at 235 bar and marginally higher at 215 bar than diesel fuel. The performance of the engine at 235 bar nozzle opening pressure was better with reduction in emissions except NOx than other nozzle opening pressures.