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。

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. Methods2D 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. ConclusionsThe 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.

国家自然科学基金资助项目（10472136），教育部博士点专项基金（20070611004）