Solve questions e, f,g and h only.

Problem 1: The total pressures and temperatures of the gas are specified for a turbofan engine with separate exhaust streams (JT3D - 3B from Pratt & Whitney, 1974). The mass flow rates in the engine core (or primary) and the engine fan are also specified for the sea level static operation. Calculate a) The engine bypass ratio a defined as the ratio of fan-to-core flow rate b) From the total temperature rise across the burner, estimate the fuel-to-air ratio and the fuel flow rate in Ibm/h, assuming the fuel heating value is QR ~ 18,600 BTU/lbm and the specific heat at constant pressure is 0.24 and 0.26 BTU/Ibm r at the entrance and exit of the burner, respectively c) The engine static thrust based on the exhaust velocities and the mass flow rates assuming perfectly expanded nozzles and compare your answer to the specified thrust of 18,000 lbs d) The engine thermal efficiency Nth e) The thermal efficiency of this engine compared to the afterburning turbojet of Problem 3.1 (worked out in class). Explain the major contributors to the differences in Nth these two engines f) The engine thrust specific fuel consumption in lbm/h/lbf g) The nondimensional engine specific thrust h) The Carnot efficiency corresponding to this engine i) The engine overall pressure ratio P3/p12 j) Fan nozzle exit Mach number [use To=T +V/2cp to calculate local static temperature at the nozzle exit, then local speed of sound a = (yRT)!?] JT3D-3B Turbofan Internal pressures and temperatures JT3 is the commercial TF version of J57 engine. It powered many aircraft including Boeing 707 and Douglas DC-8 (1 + )Cp4 T4 - Cp3 T13 = f.QR LAMAN ti e) The thermal efficiency of this engine compared to the afterburning turbojet of Problem 3.1 (worked out in class). Explain the major contributors to the differences in Nth these two engines f) The engine thrust specific fuel consumption in lbm/h/Ibf g) The nondimensional engine specific thrust h) The Carnot efficiency corresponding to this engine i) The engine overall pressure ratio p3/p12 j) Fan nozzle exit Mach number [use To =T + V2/2cp to calculate local static temperature at the nozzle exit, then local speed of sound a = (yRT)/2] JT3D-3B Turbofan Internal pressures and temperatures JT3 is the commercial TF version of J57 engine. It powered many aircraft including Boeing 707 and Douglas DC-8 (1 +1)Cp4 714 - Cp3 713 = f.QR UU 2.5 3 4 5 9 Station PA (psia) T: (F) 14.7 59 13 26 170 Vjf = 990 ft/s 63 360 200 715 190 1400 28 890 Vip = 1560 ft/s At sea level static takeoff thrust of 18000 lbs, Wat = 265 lbs/s Wab = 195 lbs/s