GE Aircraft Engine Design Challenge

1
GE Aircraft Engine Design Challenge

• Team 2
• Daniel Chaparro
• Veronica Godbey
• Jacob Katz
• Conor Lenahan
• Brian Valadez

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x.html
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Problem Statement

• Modify an existing engine to obtain 36,000 lbf
  thrust for an aircraft and an SFC below 0.320
  (lbm/hr)/lbf.

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Analytical Approach
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/technologyupgrades/spotlight_cfm563.html

• Determining of Equations using Cycle Analysis
• Expandable Baseline Code
• Analysis and Redesign of Baseline code
• Implementation of Optimization code into the
  Baseline Code
• Analysis of Optimization Results
• Discussion of the Implications of the Results

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Assumptions Concepts

• Ignoring changes of Kinetic Energy in all areas
  except inlet, nozzle, and bypass flow
• Ignoring shaft losses (perfect bearings used)
• Perfect combustion

• 1st Law
• 2nd Law
• Gibbs (combined 1st 2nd Laws)
• Conservation of Mass
• Conservation of Momentum

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Cycle Analysis Equations

• Inlet, Fan and Bypass

• Booster and Compressor

• Area of a circle

• Bypass Ratio

• Pressure ratio relations

• Bypass Ratio

• Mass Continuity

• Adiabatic efficiency relations

• Stagnation/ Static relations with Mach number

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Cycle Analysis Equations (cont.)

• Combustor

• High and Low Pressure Turbines

• Assume negligible changes in total pressure
• Energy balance/ Combustor efficiency relations

High Pressure Turbine

• Power balance Turbine work Compressor work
  plus Losses

• Turbine efficiency relationship

• Power balance Turbine work Fan work plus
  Booster work plus Losses

• Turbine efficiency relationship

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Cycle Analysis Equations (cont.)

• Nozzle

• Engine Performance

• Thrust is equal change in momentum

• Total/ Static temperature and pressure relations
  with Mach number

• Definition of speed of sound

• Definition of SFC

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Baseline Calculations

• Wrote a MATLAB script to process the
  aforementioned equations.
• Relevant variables can be modified by the user or
  another script.
• Once corrected, the code produced expected
  results

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timonials.htm
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Part A Results

• Thrust 12,662 lbf
• SFC 0.3039 (lbm/hr)/lbf
• Does NOT meet requirements as standing alone
• Would require 3 engines to meet specs

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ecma.html
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Optimization
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s/trc/2003/manual/clipart/celebrations/magglass.jp
g

• Baseline code used as basis for optimizing codes.
• Two approaches were used to model the engine
  optimization process.
• Why?
• Second opinion
• Sanity check

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Optimization Code Logic
Picture from http//fromtheflightdeck.com/Stories/
turbofan/

• Find all possible solutions for each variable
  over a logical range.
• Inlet diameter
• BPR
• Fan pressure ratio
• Booster pressure ratio
• Turbine exit temperature
• 2. Run baseline simulation on each solution.
• 3. Pick solutions that lie within customer
  requirements.
• 4. Examine trends to find optimal solution in set
  given by step 3.

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Optimization Results

• Minimum Design
• Inlet diameter 59 inches
• BPR 5.55
• Fan pressure ratio 1.582
• Booster pressure ratio 3
• Thrust 18001 lbf
• SFC .2662
• However, Does not allow for any efficiency drop

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Optimization Results

• Margin Design
• Inlet diameter 59 inches
• BPR 5.211
• Fan pressure ratio 1.53
• Booster pressure ratio 3

• At normal Efficiency
• Thrust 18487 lbf
• SFC .2783
• At 1 reduced Efficiency
• Thrust 18000 lbf
• SFC .2809

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Optimized Customer Requirements

• Resulting Per Engine Statistics
• Thrust 18,001 lbf
• SFC 0.26624 (lbm/hr)lbf

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What it all Means
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small-commercial-vessels/Passenger-Vessels/FAQ.htm

• Higher Thrust
• Only 2 engines needed for the aircraft, not 3!
• Weighs less
• Less maintenance
• Lower fuel costs
• Total thrust is
• 36,000 lbf

• Lower SFC
• Needs less fuel
• Range increased
• Carries effectively more fuel
• Runs at lower temperatures, thus prolonging blade
  life

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What it all Means (cont)
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Conclusion
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te/refresh/

• Buy our engines!