Near-nozzle characteristics of a transient fuel spray

Technical Report · Wed Nov 01 04:00:00 EST 1995

OSTI ID:121856

Koo, J Y; Martin, J K

The near-nozzle characteristics of a transient fuel spray were investigated via the measurement of drop sizes and velocities, and microphotographs of the near-nozzle region for a range of gas-to-liquid density ratios. In addition, a steady-state single-phase hydrodynamic simulation of the internal nozzle flow was performed to observe the effects of needle position on the internal flow. Measurement of droplet size and velocity near the nozzle on the edge of the spray showed that the average droplet velocity peaked during needle opening and needle closing, and changed throughout the spray event. Drop sizes tended to be small on the spray edge. Microphotographs of the near-nozzle region showed that the spray was most widely dispersed immediately after injection begins, narrowing rapidly to a constant spray angle. The same behavior was observed even for injection into near-vacuum conditions. However, once the spray was established, aerodynamic interactions were necessary for near-nozzle atomization.

• Research Organization: Wisconsin Univ., Madison, WI (United States). Engine Research Center
• OSTI ID: 121856
• Report Number(s): AD-A--295061/6/XAB; CNN: Contract DAAL03-92-G-0122
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
COMPILED DATA
DIESEL ENGINES
EVALUATION
FUEL INJECTION SYSTEMS
SPRAYS