冲击挤压式脉冲射流生成过程的简化差分模型

Simplified Finite Difference Models for Describing the Process of Percussion Pulse Jet Generation

冲击挤压式脉冲射流在高强度物料破碎领域具有较高的应用前景,其形成过程相对复杂,设计加工难度大,限制了该类型射流的发展.针对这一问题,建立了活塞的多碰撞方程,结合有限差分方法提出了用于描述冲击挤压式脉冲射流形成过程的简化数学模型.应用所建模型预测了一定工作参数下的射流压力、射流出口速度以及活塞的运动状态等随时间的变化.设计以重锤为冲击动力源的冲击挤压式射流装置,实验验证了模型的合理性.应用此模型进行数值实验,可为冲击挤压式脉冲射流装置的设计与优化提供重要参考依据.

Percussion pulse jet has powerful capabilities on hard metical fragmentation,such as rock,concrete and ceramics.However,its complicate generation process make the design works on this become hard.This is the reason why the development of this technique has been restricted for a long time.In presented works,a simplified finite difference model combined with multicollision equations of pistons was put forward.The main hydrodynamic parameters and the motion of the pistons were numerically calculated.A hammer-driven percussion jet generator was designed and implemented for the tests under same operating conditions with modeling works.By comparing the pressure data and the numerical results,those were demonstrated that the mode was reasonable and the neglects were acceptable.Conducting numerical experiments using this model,valuable reference information can be achieved for percussion pulse jet design.