전자제어식 이륜차 엔진의 연료 분사시기에 따른 증발 특성

This study investigates the spray characteristics such as evaporation rate and trajectory between twin spray for the 4-hole injector which it is applied to 4-valve motorcycle gasoline engine. Three dimensional, unsteady, compressible flow and spray behavior within the port and cylinder has been simulated using the VECTIS code. The spray characteristics were investigated at 6000RPM engine speed. Furthermore, we visualized fuel behavior in the intake port by using CCD camera synchronized with the stroboscope in order to compare with simulated result. Boundary and intial conditions were employed by complete 1-D simulation of the engine using the WAVE CFD code. Fuel was injected into the port at two time interval relative to the position of the intake valves so that the spray arrived when the valves were closed and fully open. The results showed that the trajectory of the spray was directed towards the lower wall of the port with injection against the closed valves. With open valve injection, a large portion or the fuel was lifted by the co-flowing air towards the upper half of the port, this was confirmed by simulation and visualization.