关键词: 兵器科学与技术, 凝胶汽油, 表观粘度, 撞击式雾化, 速度场

Abstract: Gel gasoline samples of QNJ-4 and QNJ-5 are prepared to investigate the influence of the factors, such as gel content, impinging angle and injection pressure, on velocity field of impingement atomization. The apparent viscosity of gel gasoline is researched by rotational rheometer with cone-and-plate configuration, and the power-low model is used to fit the apparent-viscosity to shear-rate curves of QNJ-4 and QNJ-5. The velocity field of impinging atomization with impinging angles of 60°, 75°, 90°, 105°and 120° and injection pressures of 0.50 MPa, 0.75 MPa, 1.00 MPa and 1.25 MPa is researched by the particle image velocity (PIV) system. The results indicate that the consistency index k increases with the increase in gel content maintaining while the flow index n decreases at the same time. The velocity of drops, which is produced by impinging atomization of gel gasoline, is decreased with the increase in gel content. The drop velocity on the axis of atomization area becomes smaller and smaller from impinging point to downstream, and there is the same fluctuation of the speed which is induced by the circular instable waves generating from the impact point. The core speed of gel gasoline drops is decreased with the increase in impinging angle and the reduce in injection pressure.

Key words: ordnance science and technology, gel gasoline, apparent viscosity, impinging atomization, velocity field