Spray Macro-Characteristics of Methanol-Ammonia Blend With Short Injection Durations

This study investigates the spray macro-characteristics of methanol-ammonia blend using a six-hole gasoline direct injector (GDI) coupled with Schlieren visualization. Experiments were conducted in a constant volume vessel (CVV) to characterize the spray behavior of a methanol-ammonia blend containing 9.5% methanol under high injection pressure and short injection durations. Experimental analysis focused on three critical parameters: ambient pressure (0.1/0.5/1.0 MPa), injection duration (0.25-0.80 ms), and ambient temperature (293/323/373 K). Results demonstrate that ambient pressure variations significantly influence spray penetration and spray spread angle, and under ambient pressure conditions of 0.1 MPa, the spray undergoes collapse. Conversely, injection duration and ambient temperature adjustments demonstrated minimal influence on both penetration and spread angle.