slide1 l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Rotor Design Approaches PowerPoint Presentation
Download Presentation
Rotor Design Approaches

Loading in 2 Seconds...

play fullscreen
1 / 14

Rotor Design Approaches - PowerPoint PPT Presentation


  • 269 Views
  • Uploaded on

Rotor Design Approaches. Michael S. Selig Associate Professor . Department of Aeronautical and Astronautical Engineering University of Illinois at Urbana-Champaign. Steady-State Aerodynamics Codes for HAWTs Selig, Tangler, and Giguère August 2, 1999  NREL NWTC, Golden, CO.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Rotor Design Approaches' - Thomas


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Rotor Design Approaches

Michael S. Selig

Associate Professor

Department of Aeronautical and Astronautical Engineering

University of Illinois at Urbana-Champaign

Steady-State Aerodynamics Codes for HAWTs

Selig, Tangler, and Giguère

August 2, 1999  NREL NWTC, Golden, CO

outline
Outline
  • Design Problems
  • Approaches to Design
  • Inverse Design
design problems
Design Problems
  • Retrofit Blades
  • Trade Studies and Optimization
approaches to design
Approaches to Design
  • Design by Analysis - Working “Forward”
  • Example HAWT Codes: PROP, PROP93, WT_PERF, PROPID
slide5
Inverse Design - Working “Backward”
    • Requires some knowledge of desirable aerodynamic characteristics
  • Example HAWT Code: PROPID
slide6
Optimization
    • Example problem statement: Maximize the annual energy production subject to various constraints given a set of design variables for iteration
  • Example Code: PROPGA
design variables
Design Variables

 Desire a method that allows for the specification of both independent and dependent variables

from an inverse design perspective
From an Inverse Design Perspective
  • Through an inverse design approach (e.g., PROPID), blade performance characteristics can be prescribed so long as associated input variables are given up for iteration.
  • Examples:
    • Iterate on: To achieve prescribed:

Rotor radius  Rotor peak power

Twist distribution  Lift coefficient distribution

Chord distribution  Axial inflow distribution

slide9
Caveats
    • Some knowledge of the interdependence between the variables is required, e.g. the connection between the twist distribution and lift coefficient distribution.
    • Not all inverse specifications are physically realizable. For example, a specified peak power of 1 MW is not consistent with a rotor having a 3-ft radius.
iteration scheme
Iteration Scheme
  • Multidimensional Newton iteration is used to achieve the prescribed rotor performance
  • Special "Tricks"
    • Step limits can be set to avoid divergence
    • Iteration can be performed in stages
    • Parameterization of the input allows for better convergence
propid for analysis
PROPID for Analysis
  • Traditional Independent Variables (Input)
    • Number of Blades
    • Radius
    • Hub Cutout
    • Chord Distribution
    • Twist Distribution
    • Blade Pitch
    • Rotor Rotation Speed (rpm) or Tip-Speed Ratio
    • Wind Speed
    • Airfoils
slide12
Traditional Dependent Variables - Sample (Output)
    • Power Curve
    • Power Coefficient Cp Curve
    • Rated Power
    • Maximum Power Coefficient
    • Maximum Torque
    • Lift Coefficient Distribution
    • Axial Inflow Distribution
    • Blade L/D Distribution
    • Annual Energy Production
    • Etc
  • Each of these dependent variables can also be prescribed using the inverse capabilities of PROPID
aerodynamic design considerations
Aerodynamic Design Considerations
  • Clean vs. Rough Blade Performance
  • Stall Regulated vs. Variable Speed
  • Fixed Pitch vs. Variable Pitch
  • Site Conditions, e.g. Avg. Wind Speed and Turbulence
  • Generator Characteristics, e.g., Small Turbines, Two Speed
common design drivers
Common Design Drivers
  • Generator  Peak Power
  • Gearbox  Max Torque
  • Noise  Tip Speed
  • Structures  Airfoil Thickness
  • Materials  Geometric Constraints
  • Cost