Investigation of a DISI Fuel Injector for a Close-Arranged Spray-Guided Combustion System 2002-01-1133
The spray characteristics of a single-fluid pressure-swirl outward-opening DISI injector, with a nominal operating fuel pressure of 20 MPa. are presented for various ambient pressure and temperature conditions. These data include the experimental investigations of the spray structure and its temporal development with the aid of the imaging technique; PDA measurements of the temporal evolution of the droplet size - velocity characteristics; and the LIF-PLIF measurements of the spray liquid- and-vapor phases development. The experiments pertain to atmospheric and elevated ambient air conditions (P = 0.1 - 1.2 MPa., T = 20.° - 400.° C), representative of turbo-charged and high EGR engine operating conditions.
This injector is incorporated in a single-cylinder DISI engine in a “narrow-spacing” arrangement that adopts a spray-guided air-assisted stratified-charge combustion concept, labeled “direct injection spray and air controlled” (DISAC) combustion system. The preliminary combustion data, demonstrating the fuel-saving and emissions potential of the combustion system for lean-stratified operations are presented and discussed.