真空沿面放电数值模拟中的通用抽样方法

Universal Sampling Method in Simulation of Surface Discharge in Vacuum

真空沿面放电过程中涉及的分布种类繁多、解析表达式复杂、或者不具有解析表达式而只有数据图表,其抽样工作复杂,是蒙特卡罗模拟任务设计的核心和难点。为此,设计了通用抽样接口,基于泛化机制给出了面向所有分布类型的统一抽样接口,基于特化机制针对各种分布给出了抽样接口的具体实现和最优化。设计了基于插值方法的直接抽样方法作为通用抽样接口内建的默认抽样方法,它具有最广泛的适用性并在大部分场合下具有最优抽样效率。通用抽样接口实现了三结合点场致电子发射过程中的数量、能量、方向分布以及电介质表面次级电子发射过程中的能量和方向分布的抽样,在保证最优抽样效率的同时降低了抽样工作的复杂性,实现了抽样通用性和抽样效率的统一,简化了模拟任务设计并提高了设计可靠性。

Sampling of various distributions is the key problem of Monte-Carlo simulation of surface discharge process in vacuum.Due to multiple distributions involved in surface discharge in vacuum,complex analytic expressions or only having data diagram without analytic expressions,difficulty of sampling work is increased and give rise to complexity of design of simulation task.Basing on generalization mechanism,we designed a universal sampling interface for all kinds of distribution.Meanwhile,basing on specialization mechanism,we optimized the sampling interface for various distributions.A default direct sampling method based on interpolating method was provided in the universal sampling interface,which fulfilled sampling of all kinds of distribution and had optimum sampling efficiency in the most conditions.Sampling of distribution of number,energy and direction of electrons in field emission process at triple-joint-point,and sampling of distribution of energy and direction of electrons in secondary electron emission were fulfilled by universal sampling interface.Universality and sampling efficiency were combined in universal sampling interface which simplified the design of simulation of surface discharge in vacuum,and reduced the complexity of sampling work as well as raised the reliability.