The vital role of the numerical scheme is becoming increasingly critical as the use of Computa-tional Fluid Dynamics (CFD) grows. To address the unfavorable effects experienced in low-speed flows when using the AUSM+M scheme (Improved Advection Upstream Splitting Method), cur-rent paper presents an improved approach known as Modified-AUSM+M (M-AUSM+M). This novel method offers enhanced reliability in simulating low Mach number flows, effectively miti-gating the challenges associated with low-speed symptoms encountered in the original AUSM+M scheme. The novel scheme is facilitated by the parameter-free form of the pressure diffusion term in the mass flux and the low-dissipative form of the velocity diffusion term in the pressure flux. The impacts of these critical ingredients are then thoroughly evaluated, and the different charac-teristics are explored in terms of robustness and accuracy using a wide range of low Mach test cases. The proposed scheme maintains a consistent correlation between accuracy and convergence speed. Besides, the recently devised technique demonstrates superior accuracy compared to AUSM+M and AUSM+UP schemes when dealing with low Mach flows. Furthermore, the find-ings indicate an incredible reduction in iteration numbers, ranging from 65 to 400%, by employing the enhanced scheme in low-Mach domains. In the investigation of high-Mach test cases, the newly developed method preserves the accuracy achieved by AUSM+M in high-Mach flows.

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