The expressions for the ratio of the stagnation pressure after a shock wave to the static pressure before the shock wave as a function of
Answer to Problem 121RP
The expressions for the ratio of the stagnation pressure after a shock wave to the static pressure before the shock wave as a function of
Explanation of Solution
Write the Equation 17-38 as in text book (the relation between the pressures after shock and before shock for an ideal gases).
Here, the specific heat ratio is
Write the relation between the stagnation pressure
Here, the subscript 0 indicates the stagnation state.
Write the Equation 17-39 as in text book (the expression for Mach number after shock).
Conclusion:
Rearrange the Equation (I) to obtain
Express the Equation (II) for state 2 i.e. after shock.
Substitute
Refer Equation (III).
Substitute
Thus, the expressions for the ratio of the stagnation pressure after a shock wave to the static pressure before the shock wave as a function of
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Chapter 17 Solutions
Thermodynamics: An Engineering Approach
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