| Energy and Mechanical Engineering |
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| Numerical simulation and experimental validation of internal nozzle flow characteristic of injector |
| XIE Yang, LUO Qi yuan, MA Jian, XU Cang su |
| Institute of Power Driven Machinery and Vehicle Engineering, Zhejiang University, Hangzhou 310027, China |
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Abstract The X ray phase contrast imaging technique was used to analyze the flow characteristics of internal nozzle in order to verify the simulation results. The mass flow, cavitation distribution, effective velocity at the outlet and non dimensional flow coefficients under different injection pressure conditions were considered based on the CFD software simulation combined with the experimental results. Results show that X ray phase contrast imaging technique contributes to the research, and the results accord with the simulation results. Critical super cavitation conditions are achieved easier when injection pressure rises. The growth of effective velocity at the outlet is slightly bigger than that of volume flow. Reynolds number shows positive correlation to the injection pressure, while the cavitation number decreases exponentially with increases in the Reynolds numbers. The discharge coefficient increases as the Reynolds number rises until it gets stable．
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Published: 31 March 2016
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喷油嘴喷孔内流动特性数值仿真与试验分析
采用X射线相衬成像技术研究喷嘴喷孔内试验的流动特性,验证数值仿真结果.利用CFD软件模拟得到入口压力下燃油的质量流量、空穴分布、有效喷射速度与无量纲流动系数,结合试验数据对流动特性进行分析.结果表明：X射线相衬成像技术的成像效果良好,仿真结果与试验结果吻合较好；喷射压力越高,更容易进入临界超空穴状态；喷孔出口速度的增幅略大于体积流量的增幅；雷诺数随着喷射压力的上升呈幂函数型上升,空穴数随着雷诺数的增加呈指数下降,流量系数都随着雷诺数的上升缓慢增加直至趋于稳定.
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