Caliblade Wind Turbine Analysis Tool |
||||||
Caliblade is a blade analysis software tool for small wind turbines.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
Caliblade allows designers and builders of home-built wind turbines to optimize certain design parameters such as turbine blade chord width and setting angles. To determine the optimal settings, users provide the following input to the software:
The ratio of the turbine tip speed with respect to the design wind speed, known as the tip speed ratio
The wind speed in meters per second at which the turbine is designed to operate most efficiently
The wind turbine airfoil lift coefficient
The wind turbine airfoil drag coefficient
The density of air in kilograms per cubic meters at the altitude at which the turbine will operate
The kinematic viscosity of air in square meters per second at the altitude at which the turbine will operate
The radius of the wind turbine rotor
The optimal angle of attack of the airfoil blades with respect to the oncoming wind
The number of rotor blades
The number of sections or stations along the turbine blade for analysis
From this information, the software calculates the turbine's angular velocity in radians per second and rotations per minute, and it also calculates the following for each analyzed blade section:
Annular area swept by the blade section
Outer edge of the blade section
Inner edge of the blade section
Relative or “apparent” wind velocity
Tangential velocity at a point along the turbine's radius
Optimal blade setting angle
Angle of lift vector with respect to the axis of rotation
Component of the lift vector perpendicular to the angle of rotation
Angle of drag vector with respect to the axis of rotation
Component of the drag vector perpendicular to the axis of rotation
Component of the resultant vector of the lift and drag vectors perpendicular to the axis of rotation
Power available from the area swept by blade section
Optimal airfoil chord length for the turbine blade at each blade section
Reynolds number at each blade section
The software writes its output to standard output or to a text file. The software also allows users to save settings to a file and reload those settings in another session.
The source code and binary files for this software is available at the Caliblade project summary page on SourceForge.net.
To install the Windows binary:
Download and unpack the ZIP archive of the binary release (caliblade-binary-xxx.zip) to a location on your hard drive (for example, C:\).
From the command line, run the executable file caliblade.exe.
Building the Caliblade executable for Windows from source requires Dev-C++:
Download and unpack the ZIP archive of the source release (caliblade-source-xxx.zip) to a location on your hard drive (for example, C:\).
Run Dev-C++ and open the caliblade.dev project file.
Press F9 to compile the source code and run the executable.
The Caliblade tool can be built and run in any environment that supports the GNU C Compiler (GCC) and the make utility. In Linux, for example:
Download and unpack the source tarball (caliblade-source-xxx.tar)
At the command line, change to the Caliblade directory.
Run the make command ($ make).
Run the executable ($ ./caliblade).
All command line arguments are optional. See the command summary section for information about valid values for these parameters.
caliblade [-radius <radius-value>] [-tsr <tsr-value>] [-wind <wind-velocity>] [-cl <cl-value>] [-density <density-value>] [-sections <number-of-sections>] [-cd <cd-value>] [-blades <number-of-blades>] [-attack <angle-of-attack>] [-viscosity <kinematic-viscosity-value>]
Unless values for a wind turbine are specified at the command line, Caliblade supplies default values that may be modified at run time. This section describes:
Valid commands
Command descriptions
Default value
Minimum value
Maximum value
|
Command |
Description |
Default Value |
Minimum Value |
Maximum Value |
|---|---|---|---|---|
|
W |
Change the design (w)ind speed (m/s) |
8.0 |
5.0 |
5.0 |
|
T |
Change the (t)ip speed ratio |
6.0 |
4.0 |
9.0 |
|
R |
Change the turbine (r)adius (m) |
1.0 |
0.25 |
5.0 |
|
C |
Change the airfoil lift (c)oefficient. |
0.8 |
0.5 |
2.0 |
|
D |
Change the arifoil (d)rag coefficient |
0.02 |
0.01 |
0.1 |
|
A |
Change the (a)ir density (kg/m3) |
1.225 |
0.5 |
1.5 |
|
V |
Change the kinematic air (v)iscosity (m2/s) |
0.0000147 |
0.0000124 |
0.0000301 |
|
N |
Change the optimal a(n)gle of attack (degrees) |
5 |
1 |
10 |
|
B |
Change the number of (b)lades |
2 |
2 |
3 |
|
E |
Change the number of s(e)ctions to analyze |
10 |
5 |
50 |
|
P |
(P)rint blade analysis to screen |
|
|
|
|
F |
Print blade analysis to (f)ile |
|
|
|
|
H |
S(h)ow current turbine property settings |
|
|
|
|
S |
(S)ave settings to file. |
|
|
|
|
O |
(O)pen settings file |
|
|
|
|
L |
(L)ist available commands |
|
|
|
|
Q |
(Q)uit program |
|
|
|
The P and F commands print a table of analysis results for each blade section. This section defines the analysis data.
|
Fields |
Units |
Description |
|---|---|---|
|
Area |
m2 |
Annular area swept by the blade section |
|
R |
m |
Outer edge of the blade section |
|
r |
m |
Inner edge of the blade section |
|
WA |
degrees |
Relative or “apparent” wind velocity |
|
Vt |
m/s |
Tangential velocity at a point along the turbine's radius |
|
SA |
degrees |
Optimal blade setting angle |
|
LA |
|
Angle of lift vector with respect to the axis of rotation |
|
LY |
|
Component of the lift vector perpendicular to the angle of rotation |
|
DA |
|
Angle of drag vector with respect to the axis of rotation |
|
DY |
|
Component of the drag vector perpendicular to the axis of rotation |
|
Power |
Watts |
Power available from the area swept by blade section |
|
Chord |
cm |
Optimal airfoil chord length for the turbine blade at each blade section |
|
Re |
|
Reynolds number at each blade section |
|
Copyright (C) 2006 Richard Schetnan |
|||||