# 12.1.1.1: Introduction to Zero Inclination

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Fig. 12.3 A typical oblique shock schematic.

What happens when the inclination angle is zero? Which model is correct to use? Can these two conflicting models, the oblique shock and the Prandtl–Meyer function, co-exist? Or perhaps a different model better describes the physics. it was assumed that Mach wave and oblique shock co–occur in the same zone. Previously (see Section ), it was assumed that normal shock occurs at the same time. In this chapter, the stability issue will be examined in greater detail.