高压条件下燃料喷雾液滴粒径，速度和形状的耦合研究

In the present work the process of a transient fuel injection in a constant high-pressure atmosphere is investigated experimentally. As fuel, dimethyl ether (DME) is used. The goal is to receive new information about the charac-teristics referring to the droplet size, the droplet velocity and the droplet shape in the jet. The high-pressure chamber has a constant pressure of 2 MPa and the fuel spray is injected with a pressure of 6 MPa, 7 MPa and 8 MPa. The spray is analysed by a Shadow-Sizing-technique and digital image analysis with temporal and spatial resolution, which even allows investigating non-spherical droplets. The correlations of d velocity and droplet shape are presented as Joint Probability Density Functions (JPDF). The conclusion of the investigation shows that little increase of the injection pressure has a remarkable effect on the droplet size. Furthermore, the centricity is widely influenced by the injection pressure. With lower injection pressure the droplet velocity decreases. Moreover, the droplets mean diameter shows a significant decrease with increasing time after the injection