# 12.2.3: Application of Oblique Shock

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Fig. 12.13 Two variations of inlet suction for supersonic flow.

One of the practical applications of the oblique shock is the design of an inlet suction for a supersonic flow. It is suggested that a series of weak shocks should replace one normal shock to increase the efficiency (see Figure (??)). Clearly, with a proper design, the flow can be brought to a subsonic flow just below $$M=1$$. In such a case, there is less entropy production (less pressure loss). To illustrate the design significance of the oblique shock, the following example is provided.

Example 12.5

Fig. 12.14 Schematic for Example (??).

The Section described in Figure and efoblique:fig:inletEx} air is flowing into a suction section at $$M=2.0$$, $$P=1.0[bar]$$, and $$T=17^{\circ}C$$. Compare the different conditions in the two different configurations. Assume that only a weak shock occurs.

Solution 12.5

The first configuration is of a normal shock