| 摘要 |
<p>The fuel injector (10) has several swirl passages (58) in a fuel swirl and needle guide member (34) that direct swirl fuel onto the frusto-conical surface of a valve seat member (48) that is disposed at the injector's nozzle end (30). The needle lift is such that with the needle (30) unseated to open the injector (10) to flow, the swirl fuel is throttled as it passes between the rounded tip end of the open needle (30) and the frusto-conical surface of the seat member (48). The throttling tends to spread the swirl flow so that it is more uniform in the circumferential sense. If the injector (10) is closed before equilibrium flow occurs, a toroidal shaped fuel cloud is created; if the injector (10) is closed after equilibrium flow occurs, an ellipsoidal shaped fuel cloud is created.</p> |
