mid135s10

# mid135s10 - M 2 = 2 0 Assuming one-dimensional Fow in the...

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MAE135 MIDTERM 06-MAY-2010 Open book (Anderson only), notes and homeworks. Assume calorically-perfect air ( γ = 1 . 4, R = 287 J/Kg K) for all problems. 80 minutes time limit PROBLEM 1 (5 points) Consider Fow through a normal shock. Are any of the following statements incorrect? If so, indicate the erroneous statement(s) and explain why. You must explain correctly to get credit! A. T 0 = constant B. pM/ T = constant C. pv γ = constant D. p + 1 2 ρu 2 = constant E. h + 1 2 u 2 = constant PROBLEM 2 (5 points) 1 V =600 m/s 1 1 p =10 kPa T =224 K 2 p =5 kPa Consider isentropic air Fow over an airfoil. The freestream conditions are V 1 = 600 m/s, T 1 = 224 K, and p 1 = 10 kPa. On the crest of the airfoil, the pressure is p 2 = 5 kPa. Calculate the velocity V 2 on the crest of the airfoil. PROBLEM 3 (10 points) 2 M =2.0 1 M =3.0 Insulated 1 2 ±low through a converging-diverging nozzle is accelerated to M 1 = 3 . 0. The nozzle is connected to a long constant-area, insulated pipe. At the exit of the pipe, the Mach number is measured to be
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Unformatted text preview: M 2 = 2 . 0. Assuming one-dimensional Fow in the pipe, answer the following: (a) What could be the cause of the reduction in Mach number? (b) Calculate the temperature ratio T 2 /T 1 . (c) Calculate the pressure ratio p 2 /p 1 . PROBLEM 4 (10 points) A* A=3A* A* A=3A* (b) (a) 500 kPa 500 kPa A normal shock sits in a test section with A/A * = 3 . 0. The reservoir pressure is p 1 =500 kPa. A very skinny Pitot probe (no blockage e²ects) is placed in two positions: (a) with the inlet just past the shock; (b) with the inlet just ahead of the shock. Assuming isentropic Fow except across shocks, ³nd: (a) The pressure that the Pitot probe measures when its inlet is past the shock. (b) The pressure that the Pitot probe measures when its inlet is ahead of the shock. 1...
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## This note was uploaded on 08/31/2010 for the course ENGRMAE 135 taught by Professor Staff during the Spring '08 term at UC Irvine.

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