用于薄壁件辅助支撑的脉冲射流动态特性研究

摘要

为解决射流支撑工艺背后射流稳定性难题,基于流体体积函数模型和Realizable k-ε模型,运用ANSYS/Fluent对理想条件下单脉冲射流和双脉冲射流的形成过程、流场结构和冲击特性进行数值模拟,同时采用基于弹性光顺法和局部重构法的CFD动网格技术研究实际工况下隔板对截断式脉冲射流流场结构的影响规律.结果表明:连续的脉冲射流冲击力波形与薄壁件铣削力波形具有很好的一致性,脉冲射流作为薄壁件铣削的辅助支撑是可行的;理想双脉冲射流情况下前面射流束会影响到后面射流束的冲击力幅值、持续时间和作用范围;双隔板布置相比于单隔板能产生流场结构更好、可控性更高的脉冲射流.%To solve the problem of jet stability behind the technology of jet support, ANSYS/Fluent was used to study the formation process, flow-field structure and impact characters of single and double pulsed water jet under ideal conditions, based on volume of the fluid model and Realizable k-ε model.Moreover, the influence of one baffle or two baffles on the flow-field structure of pulsed water jet was simulated by using dynamic mesh technique combining flexible smoothing with local re-drawing.The results show that the waveform of impact force caused by continuous pulsed water jet has good consistency with the waveform of milling force and it is feasible that pulsed water jet is used as the auxiliary support of thin-walled parts.The first water jet beam's wake can affect the magnitude, the duration and the scope of impact force caused by the second water jet beam.Compared with a single baffle, double baffle arrangement can produce a pulsed water jet to be better in flow-filed structure and more controllable.