Calculation of spray collapse in multiple-hole gasoline direct injectors based on the spray momentum theory

In this study, a new method to calculate the spray collapse in multiple-hole gasoline injectors was developed. The theoretical calculation method was proposed by applying the extended spray momentum theory. In this theoretical calculation method, the deflection of the spray direction toward the injector axis was calculated serially based on the imbalance of the momentum of backward gas-flow surrounding sprays. The calculation and spray observation for validation against the calculation result were performed under conditions with and without flash boiling.