Using the results of linearized theory, calculate the lift and wave-drag coefficients for an infinitely thin flat plate in a Mach 2.6 freestream at angles of attack of
(a)
Compare these approximate results with those from the exact shock- expansion theory obtained in Problem 9.13. What can you conclude about the accuracy of linearized theory in this case?
(a)
The lift and wave drag coefficients and comparison of accuracy.
Answer to Problem 12.1P
The lift and drag coefficients are
Explanation of Solution
Given:
The angle of attack is
The Mach number is
Formula used:
The expression for lift is given as,
The expression for drag is given as,
Calculation:
The coefficient of lift can be calculated as,
Refer to problem 9.13, the error can be calculated as,
The coefficient of drag can be calculated as,
Refer to problem 9.13, the error can be calculated as,
Conclusion:
Therefore, the lift and drag coefficients are
(b)
The lift and wave drag coefficients and comparison of accuracy.
Answer to Problem 12.1P
The lift and drag coefficients are
Explanation of Solution
Given:
The angle of attack is
The Mach number is
Formula used:
The expression for lift is given as,
The expression for drag is given as,
Calculation:
The coefficient of lift can be calculated as,
Refer to problem 9.13, the error can be calculated as,
The coefficient of drag can be calculated as,
Refer to problem 9.13, the error can be calculated as,
Conclusion:
The lift and drag coefficients in first case are
(c)
The lift and wave drag coefficients and comparison of accuracy.
Answer to Problem 12.1P
The lift and drag coefficients are
Explanation of Solution
Given:
The angle of attack is
The Mach number is
Formula used:
The expression for lift is given as,
The expression for drag is given as,
Calculation:
The coefficient of lift can be calculated as,
Refer to problem 9.13, the error can be calculated as,
The coefficient of drag can be calculated as,
Refer to problem 9.13, the error can be calculated as,
Conclusion:
Therefore, the lift and drag coefficients are
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