Influence of Nozzle Structure Parameters on Flow Characteristic in Three-dimensional Flow Field Simulation
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摘要: 为了改善柴油机D6114喷油嘴291 DLLA150 FC PV01内部燃油流动状况,使喷入气缸内的燃油达到较好的雾化质量,在原有喷嘴基础上,针对喷嘴结构参数长径比、喷嘴入口过渡圆角及喷孔锥角设计了9种方案。在CFD(计算流体动力学)软件中建立了喷嘴内部流场的三维模型,对整个流场区域进行了流体动力学模拟计算。分析了喷嘴结构参数对喷孔内部空化程度、湍动能及流速的影响,得出:随着长径比(L/D)的减小,燃油在喷孔中的空化程度增强,湍动能减小,流速增加;随着过渡圆角与直径比(r/D)的增大,喷孔内部流体空化程度增强,流速增大,湍动能减弱;随着喷孔锥角(θ)的增大,喷孔内燃油空化程度加强,湍动能减弱。Abstract: In order to improve the internal fuel flow conditions in the nozzle 291 DLLA150 FC PV01 of the diesel engine D6114 and make fuel sprayed into the cylinder to obtain good atomization quality, nine schemes were de-signed based on the nozzle structure parameters: length-diameter ratio, the round angle-radius of nozzle inlet and orifices angle. Three-dimensional model of the internal nozzle flow field was established, and simulated using the CFD (Computational Fluid Dynamics) software. The influence of spray nozzle structure parameters on hole internal cavitation degree, turbulent kinetic energy and flow velocity was analyzed. The results show that with the decreasing of length-diameter ratio (L/D), the cavitation degree of fuel in the orifice and the velocity will increase, but the turbulent kinetic energy will decrease; with the increasing of round angle-radius to diameter ratio (r/D), the cavi-tation degree of fuel in the orifice and the velocity will also increase while the turbulent kinetic energy will de-screase; with the increasing of orifices angle (θ), the cavitation degree of fuel in the orifice will increase, and the turbulent kinetic energy will decrease.
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Key words:
- atomization /
- diesel engines /
- engine cylinders /
- kinetic energy /
- orifices
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