Liquid injectors are found in many kinds of applications. In this work, we focus on the fuel injector of an automobile engine. It is important to predict the properties of the spray in order to improve the fuel spray pattern of the injector. We selected the spray cone angle and the flow rate distribution among the properties of the spray, and predicted them by numerically simulating the internal flow in the fuel injector. The finite volume method with an unstructured mesh was used in this numerical simulation. The spray cone angle was predicted by extrapolating the velocity vectors at the nozzle outlet. The flow rate distribution was predicted by numerically detecting the number of the flow path lines at the nozzle outlet. Moreover, the numerically simulated spray cone angle and the flow rate distribution agree well with experimentally measured ones.
