中文摘要：

采用约化摄动法,得到描述无磁场等离子体中离子声波传播的modified Kadomtsev-Petviashvili（mKP）方程,构造有限差分格式对mKP方程的一类特殊孤立波解的稳定性进行数值研究.数值结果表明：在两种特殊情形的初始扰动下,该孤立波均不稳定.

英文摘要：

The reductive perturbation method is employed to describe the behaviour of ion-acoustic waves for plasmas in the absence of magnetic field, leading to a type of modified Kadomtsev-Petviashvili equation. The stability of a special type of solitary wave solutions for the modified Kadomtsev-Petviashvili equation is investigated with a finite difference scheme. The numerical results show that this solitary wave is unstable under two particular initial perturbations.