Spray Characterization in a DISI Engine During Cold Start: (2) PDPA Investigation

摘要: Spray angle and penetration length data were taken under cold start conditions for a Direct Injection Spark Ignition engine to investigate the effect of transient on spray development. The results show that during start, development depends primarily fuel pressure, followed by Manifold Absolute Pressure (MAP). frequency had little this single hole, pressure-swirl injector was characterized using high speed imaging. three different regimes. Regime 1 comprised pressures from 6 ? 13 bar, MAPs 0.7 large pre-spray along with drop sizes. lengths comparatively small. 2 30 39 bar 0.51 0.54 bar. A sizes still present but reduced compared 1. typically larger then in 3 65 102 0.36 0.46 fully developed hollow cone structure recirculation vortices at edges spray, which constricted angle. similar 2, while increased. size 2. In all regimes, decreasing MAP enlarged angle, injection not significant factor.