Characterization of prototype high-pressure swirl injector nozzles, part II: CFD evaluation of internal flow

Static flow rate and initial cone angle of high-pressure swirl injector noz zles were characterized through measurements and computations as a prelimin ary optimization process of nozzle design. Prototype injectors were fabrica ted by modifying commercial multipoint injection (MPI) nozzles. Measurement s of static flow rate were compared with the computations, and the agreemen ts were satisfactory in values and tendencies with respect to the nozzle ge ometry and the needle lift. Initial cone angle was calculated and compared with measurements by the direct photographic imaging method. It could be pr edicted satisfactorily by introducing an adequate correction factor. Consid ering these cross-checking for a validation of the computational model, a p arametric study was carried out to predict the flow rate and the initial co ne angle with respect to selected design parameters.