【摘要】 目的通过数值模拟研究体外冲击波粉碎结石术(extracorporeal shock wave lithotripsy,ESWL)中单脉冲与双脉冲两种不同情况下的压力场,并对两者结果进行比较和分析。方法利用2D轴对称Euler方程和混合网格改进的时空守恒元解元(space-time conservation element and solution element,CE/SE)数值格式,对ESWL中冲击波水下传播的压力场进行模拟。结果 CE/SE方法成功地追踪了冲击波波阵面传播情况,数值解较好地展示了ESWL焦点附近的冲击波聚焦特性:在焦点附近双脉冲产生的压力峰值约为单脉冲的两倍,越靠近焦点处双脉冲ESWL所得到的碎石效率相较于单脉冲时越高,且在焦点附近产生正压随后出现了绝对值极高的负压。结论采用液电双脉冲波源机型能够有效地提高碎石效率,并且冲击波聚焦时出现空化是不可避免的。上述结论为ESWL碎石机的设计制造及临床应用提供了可靠的数值模拟结果。更多还原

【Abstract】 Objective To study the pressure field with the single-pulse and the dual-pulse for extracorporeal shock wave lithotripsy(ESWL) by numerical simulation,and to compare and analyze the results.Methods 2D axisymmetric Euler equations and hybrid grids improved CE/SE numerical scheme were employed to simulate the pressure field of underwater shock wave in ESWL.Results The CE/SE shock wave dynamics method could successfully track the transmission of shock wave front,and the simulation solution could preferably reveal the focusing properties near the focus of ESWL: the pressure of dual-pulse was about the twice that of the single——pulse near the focus,and the higher lithotriptic efficiency could be achieved when the dual-pulse was much closer to the focus than the single-pulse.A negative pressure with high absolute value was observed after the positive pressure occurred near the focus.Conclusions The adoption of electro-hydraulic lithotripter could effectively improve the efficiency of stone comminution and the cavitation of shock wave focus was unavoidable,which provided a reliable numerical simulation result for the design and application of ESWL lithotripter in clinic.更多还原