UPRM INME5701 Quiz

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UPRM INME5701 Quiz 8/29/06
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Problem Statement A turbojet engine ( single
stream ) has been designed and tested as
described below. Find the engine thrust by
completing the blanks in the attached
sheet. Known information Pam 3.468 psia, Tam
394.1 R, V0 800 ft/s. P3/P2 20, T4 3000
R. hc 85, ht 90 , Burner DP/P 0.05. Inlet
and exhaust nozzle are ideal, i.e., no
losses. Fuel and air properties plus constants (
gc, J ) as specified in problem. Assumptions Con
stant properties for flow through the engine.
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JET ENGINE THERMODYNAMIC CALCULATIONS-
PROBLEM 2 (IN FLIGHT-fixed Properties) Pressure
- 3.468


psia

P/P .05 Wa 100 lbs/sec
Press Ratio 201
Eff. 85 Shaft pwr
-BTU/Sec Eff. 90 Vflt 800 ft/sec

Wf
lbs/sec



Temp (R) 394.1

3000

Enthalpy-


BTU/LBm BURNER ENERGY (HV 18400
BTU/Lb)
Cp 0.24 BTU/Lbm-Degree

R
53.3 Ft-Lbf/Lbm-Degree

J 778
Ft-lbf/BTU THRUST
gc 32.174 lbm-ft/lbf-s2


htot - hstatic V
Fstr,out Fstr,in
Fnet