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Show The components of c were A , 9 , d , and 9, . The spray pattern s s m d coefficient was defined so that the actual spray was divided by the theoretical spray, where the spray was defined as the spray area divided by the spray angle: This coefficient contains components that were experimentally measured; therefore, the INOP was varied from 2250 psig to 3500 psig generating data for a spray pattern dependency, a plot of e as a function of INOP, to obtain equivalent INOP's. The equivalent INOP, INOP , was the INOP required to obtain the same e for all fuels as that for DF2 at manufacturer's specifications (INOP=2750 psig). The coefficient for DF2 at INOP=2750 psig was considered the standard because it was assumed that the manufacturer had conducted sufficient testing to acquire proper atomization for their engine at this pressure. Engine Parameters The engine used for testing was a 4 cylinder, 172 CID Ford diesel tractor engine with a bore of 3.90, stroke of 3.60, and a 16.8:1 compression ratio (27). To meet SAE requirements regarding engine conditions for testing, the cylinder heads were removed and the combustion chambers cleaned; the injectors were removed and cleaned in an ultra-sonic bath, and the manufacturer's specifications were set. These included; Tightening of bolts to their correct torque, Setting injection timing (18 BTDC), Setting INOP (2750 psig), Setting valve lash (0.015 in.). -25- |