Question: A simple turbojet engine ( zero bypass, no afterburner ) is designed for flight at 1 0 km above sea level and Mach 0 .

A simple turbojet engine (zero bypass, no afterburner) is designed for flight at 10 km above sea level and Mach 0.72. The compressor pressure ratio is 12 and the maximum allowable engine temperature is 1650 K . You may assume standard air properties throughout, typical values of component efficiencies1, and a fuel heating value of \(42,000\mathrm{~kJ}/\mathrm{kg}\). The target thrust is \(25,000\mathrm{~N}\) at the stated conditions.
a) Calculate (and state) the required mass flow rate (i.e., "size" the engine).
b) Find the Thrust Specific Fuel Consumption under these conditions and state the value as \(\mathrm{X}\mathrm{hr}^{-1}\).
c) Examine the nozzle exit conditions. Is the nozzle properly matched, over-expanded or under-expanded?
d) Run a parametric analysis showing the effect of changing the compressor pressure ratio and the peak temperature by \(\pm 20\%\) from the design values. Show a contour plot of the effect of these changes with Thrust along the \( x \) axis and TSFC on the \( y \)-axis. Add turbine exit temperature as an overlaid contour parameter (Hint: this is one of those colorful plots discussed in class).
e) Comment briefly on the results from step d. What design changes seem to result in performance improvement? The same core engine specifications 2 will now be used to develop a two-shaft turbofan that 'will also provide \(25,000\mathrm{~N}\) thrust at 10 km and Mach 0.72. Use typical values for component efficiencies, but force the fan, which will have a pressure ratio of 1.4, to have an isentropic efficiency of \(0.86^{3}\).
f) Seek the optimum bypass ratio that will give best fuel consumption.
g) State your final results for mass flow rates, bypass ratio, and TSFC, all at the stated flight conditions.
h) Run both engines (baseline turbojet and turbofan) at sea level, static conditions, and state the thrusts generated (2 answers). Comment on any anomalous results.
Please show no more than two GasTurb printouts in support.
A simple turbojet engine ( zero bypass, no

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