Effect of Ambient and Fuel Pressure on Nozzle Spray Angle

Abstract

Abstract Diametral samples across the fuel spray at a distance of 4½ in. from the nozzle tip were obtained for ten centrifugal-type nozzles of 9 to 100-gph capacity, having nominal spray angles of 45 and 80 deg. The data were taken over a fuel-pressure range of 25 to 400 psi and for ambient pressures from 0.1 to 8 atm. These diametral spray distributions were reduced to equivalent spray-angle values which when plotted against ambient and fuel pressure provided a summary of the pressure effects on the spray angle. It was found that the spray angle decreased markedly with increasing fuel and ambient pressure. An explanation of the phenomenon is given. The equivalent spray angle was found to be a function of the product of fuel pressure drop and ambient gas density to the 1.6 power, i.e., Pγ1.6.