给出了分离系数矩阵（ＳＣＭ）求解欧拉方程组时系数矩阵的直接分离公式，减少和简化了应用该方法时的矩阵运算。参照Ｂｅａｍ－Ｗａｒｍｉｎｇ显式格式构造与ＳＣＭ方法一致的内点差分格式，并分析了它的数值特性。对有斜激波的跨音速内流场进行了数值仿真。计算中采用变系数的当地时间步长，加快了流场达到稳态的收敛速度。计算无需引入任何人工参数，计算值与实验结果吻合。 The direct separation formula of coefficient matrix when Euler equations is separated by the separation coefficient matrix (SCM) is given, which reduces and simplifies the matrix operation when the method is applied. According to the Beam-Warming explicit format, the interior difference scheme is constructed according to the SCM method, and its numerical characteristics are analyzed. The numerical simulation of transonic internal flow field with oblique shock was carried out. The use of local time steps with varying coefficients in the calculation speeds up the steady-state convergence of the flow field. Calculation without the introduction of any artificial parameters, calculated values ​​and experimental results.