Experimental investigations of spray/wall impingement

A complete set of spray impingement data, including incoming and secondary droplet size and velocity, spray visualization images, and deposited film shape and thickness, are presented. A pintle injector was used for all measurements, and the fuel used was iso-octane. The fuel impinged upon a flat Plexiglas plate, with an average surface roughness of 40 Å. Three separate impingement angles were considered: 30°, 45°, and 60° from normal. A phase Doppler particle analyzer (PDPA) was used to characterize the incoming fuel spray as well as the secondary droplet cloud. An unintensified CCD camera was used to take images of the fuel film formation and the evolution of the secondary droplet cloud. Finally, an optical, nonintrusive technique was used to determine the thickness of the deposited fuel film. Calibration of the optical technique was performed, and good agreement was shown over the entire range of film thickness. This set of data provides detailed information necessary for verifying spray impingement and film deposition and evolution models.