4.2.1.11. Appendix
4.2.1.11.1. AeroDyn Input Files
In this appendix we describe the AeroDyn input-file structure and provide examples.
1) Baseline AeroDyn Driver Input File:
(driver input file example):
The driver input file is only needed for the standalone version of AeroDyn and contains inputs normally generated by OpenFAST, and necessary to control the aerodynamic simulation for uncoupled models.
AeroDyn Driver Timeseries Input File
(driver timeseries input file example):
The timeseries input file for a case in the AeroDyn driver allows the parameters
to vary with time. This feature can be useful for debugging the aerodynamic response
outside of OpenFAST.
2) Multi-rotor AeroDyn Driver Input File
(driver input file example):
3) AeroDyn Primary Input File
(primary input file example):
The primary AeroDyn input file defines modeling options, environmental conditions (except freestream flow), airfoils, tower nodal discretization and properties, tower, hub, and nacelle buoyancy properties, as well as output file specifications.
The file is organized into several functional sections. Each section corresponds to an aspect of the aerodynamics model.
The input file begins with two lines of header information which is for your use, but is not used by the software.
Airfoil Data Input File
The airfoil data input files themselves (one for each airfoil) include tables containing coefficients of lift force, drag force, and pitching moment versus AoA, as well as UA model parameters. In these files, any line whose first non-blank character is an exclamation point (!) is ignored (for inserting comment lines). The non-comment lines should appear within the file in order, but comment lines may be intermixed as desired for reading clarity.
5) Blade Data Input File
(blade data input file example):
The blade data input file contains the nodal discretization, geometry, twist, chord, airfoil identifier, and buoyancy properties for a blade. Separate files are used for each blade, which permits modeling of aerodynamic imbalances.
4.2.1.11.2. AeroDyn List of Output Channels
AeroDyn has regular outputs (see Section 4.2.1.3.2.13) and nodal outputs (see Section 4.2.1.3.2.14).
The coordinate systems used for the outputs (labeled, i, h, p, l, a) are described in Section 4.2.1.2.
A comprehensive, up-to-date list of all possible output parameters is given in the Excel file OutListParameters.xlsx, in the tab AeroDyn and AeroDyn_Nodes for the regular and nodal outputs, respectively.
The names in the Excel file are grouped by meaning, but can be ordered in the OUTPUTS section of the AeroDyn input file as you see fit.
Regular outputs
Some examples of regular outputs are given below (see OutListParameters.xlsx for an exhaustive list):
RtAeroCp : aerodynamic power coefficient.
\(B \alpha N \beta\), refers to output node \(\beta\) of blade \(\alpha\), where \(\alpha\) is a number in the range [1,3] and \(\beta\) is a number in the range [1,9], corresponding to entry \(\beta\) in the \(\textit{BlOutNd}\) list.
\(\textit{TwN}\beta\) refers to output node \(\beta\) of the tower and is in the range [1,9], corresponding to entry \(\beta\) in the \(\textit{TwOutNd}\) list.
Nodal outputs
An example of nodal outputs is described below (see OutListParameters.xlsx for an exhaustive list).
The x-component of the undisturbed flow velocity (VUnd) at all blade nodes in the inertial frame (\(i\)) is requested by placing \(VUndxi\) in the AeroDyn nodal output list. This will result in output channels of the form AB\(\alpha N\beta\) Vundxi, for node \(\beta\) of blade \(\alpha\), where \(\alpha\) is a number in the range [1,3] and \(\beta\) is a number in the range [1,999] corresponding to the index of the AeroDyn blade node.