ME326_HW10_9NOV2011

# ME326_HW10_9NOV2011 - Problem#3 Repeat problem#1 but this...

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ME 326-Homework Assignment #10 Due: 9 November Topic: Brayton Cycle Text: Chapter 9.6 Problem #1: Air enters a gas-turbine engine at 50 °F and 14.7 psia and is compressed to 120 psia. The temperature at the inlet of the turbine is 2100 °F. Modeling the engine with an Ideal Brayton Cycle using air with variable specific heat determine: a) The temperature of the turbine exhaust (°F), b) the rate of specific heat input to the air (BTU/lb m ), c) the back-work ratio, d) the thermal efficiency. Note: include a schematic of the engine and T-s diagram with states numbers indicated on the diagram. Problem #2: The gas-turbine engine described in problem #1 has an air flow rate of 350 ft 3 /sec at the inlet. For this engine determine: a) the mass flow rate of air (lb m /s), b) the volumetric flow rate at the turbine exhaust (ft 3 /sec), c) the rate of heat input (BTU/sec), d) the power produced (hp).
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Unformatted text preview: Problem #3: Repeat problem #1, but this time using assuming the compressor and turbine have isentropic efficiency of 90%. Problem#4: Repeat problem #2 using the irreversible Brayton cycle model from problem #3. Problem #5: Beginning with the irreversible Brayton cycle model from problem #3, add a regenerative heat exchanger to heat the air at the compressor exit by using the exhaust from the turbine. Be sure to redraw the engine schematic and T-s diagram, adding new state labels as necessary. For this problem determine: a) The temperature of the turbine exhaust (°F), b) the rate of specific heat input to the air (BTU/lb m ), c) the back-work ratio, d) the thermal efficiency. [Note that Q in includes ONLY to the heat added during the combustion process]. Problem #6: Repeat the calculations for problem #2 using the regenerative Brayton cycle studied in problem #5....
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## This note was uploaded on 12/14/2011 for the course ME 326 taught by Professor Schmidt during the Fall '07 term at University of Texas.

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