Experimental Diagnostics and Investigations on Cavitation in Engine Injector Nozzles

Abstract Cavitation is a crucial phenomenon in engine injector nozzles. Whether it is desired in order to improve atomization, as in gasoline nozzles, or it should be suppressed to avoid damage, as in diesel nozzles, it plays a role in the injection process. However, it is a phenomenon that is challenging to investigate experimentally, as it happens inside the nozzle and cannot be observed directly. This chapter provides an overview of the appearance and role of cavitation in different injection processes, presents nonoptical and optical experimental techniques to investigate the phenomenon, and discusses their application to illustrate beneficial as well as destructive influences of cavitation on the injection process and nozzle.