Constant-Pressure Adiabatic

University:
Duke University
Course:
PHYSICS 363 | Thermal Physics
Academic year:

2023
Views:

87

Pages:

3
Author:

Pemuda H

Iminl ()minL x = 1+ Xmink Unus+ 1+xmint Weighted specific heat: rCp9CPa 1+minl (x-1) minl 1+xminl Sa + AS' Constant-Pressure Adiabatic Flame Temperature (CPAFT) (5.3) temperature that results when a flow is burned adiabatically during. a constant pressure process Q=0=hpr-hre hpr=hre Real Cycles wl Actual Medium ((0.7). Turbojet (16.7.1) Look at Ex. 6.7. 1 Turbofan (6.7.2). Assuming Ae (Pe-Pa) << ma [(1+f)ue-u] T=ma (ue-4) Want a significant mass flow rate to which the engine imparts a little bit of energy GUEST LECTURER! Tu maulue-u) 2p ma[(1+4)-]ina(-) T For de ma u Why does lower de mean higher ?p? Because more Kinetic energy gets transferred to the turbine blades BPR = Intip of fon Mgas generator mac 1+ BPR= Mtotal Maus generater Look at Ex. 6.7.2 for helicopters (300 RPM) Turboprop and Turboshaft ((6.7.3) Combines the advantages of a turbojet to the efficiency of a propeller 90% of thrust from propeller, 10% from engine I shaft horsepower (736W) = 2.5 lbf of thrust (11.IN) Look in notes for rest of egs. and Ex. 6. 7.3 Propeller spins at about 3,000 RPM while the shafts spin at 20,000 RPM On final, will be given pictures of engines and be asked to identify it. and list components Ramjet (6.7.4) Sidenote: Scramjet- Supersonic combustion ramjet Work from M>2.5, but typically for M>3 Fans and Compressors (7.3) Purpose: to raise pressure for a more efficient combustion Look at advantages Veise-fixed airfoil →Blade-axially rotating airfoil Axial compressor air leaves the same direction as it came in.. Centrifugal compressor air leaves radially large frontal area so don't want to fly fast, ma< 25 Blades will typically sit on discs, drums, or disedrums. Centrifugal compressor can be found in hair dryers, are pumps, leafblowers.... From this point on: Look at notes Final: Theory is not cumulative, but problems are. • Print out table (all of it) Can have cheat sheet