7/24/2019 gas dynamics question paer

1/1

MES COLLEGE OF ENGINEERING AND TECHNOLOGY

KUNNUKARA

SECOND SERIES EXAMINATION-OCTOBER 2015

ME010 703: GAS DYNAMICS AND JET PROPULSION

Time: 2 hrs Maximum Mark: 50

Part AAnswer all questions

Each question carries 3 marks

1. What are the assumptions made for Rayleigh flow?

2. What is the limiting Mach number in isothermal flow?

3. Give two useful applications of the shock waves.

4. Define the terms friction choking and thermal choking with reference to Fanno and

Rayleigh flow.

5. What do you mean by oblique shock waves?

5x3=15 marks

Part B

Answer all questions

Each question carries 5 marks

6. Describe the events leading to the formation of shock waves. Explain why expansion

shocks are not possible

7. Explain how a Fanno line is drawn in h-s diagram.

8.

Diffrentiate between Fanno and Rayleigh flow.

3x5=15 marks

Part C

Answer any one of the following

9. Find out the location of maximum entropy and maximum enthalpy on a Rayleigh line

OR

10. Air is discharged from a reservoir at pressure 6.91 bar and temperature 3250C througha nozzle to an exit pressure of 0.98 bar. If the flow rate is 3600 kg/hr. Determine for

isentropic flow : (a) Throat area , throat pressure and velocity. (b) Exit area and exit

mach number (c) Maximum velocity.

11. A conical diffuser has entry and exit diameters of 15 cm and 30 cm respectively. The

pressure, temperature and velocity of air at entry are 0.69 bar , 340K and 180m/srespectively. Determine (a) exit pressure (b) exit velocity (c) force exerted on the

diffuser walls. Assume isentropic flow , = 1.4 ,cp= 1.00 kj/kg K.

OR

12. Derive governing equations for normal shock waves. From these derive Hugoniot

equation.

2x10=10marks