Software Available for Download    

Wind Turbine Motion Simulation using 1-2-3 Sequenced Euler Angles

A time-domain motion simulator in which the rotational dynamics of the structure are computed using Eulers Equations of Motion, based on a 1-2-3 sequence of Euler Angles. The primary benefit of the 1-2-3 sequence over the 3-1-3 sequence is that for small angles the 1-2-3 sequenced Euler angles roughly correspond to the traditional roll, pitch and yaw motions of the floating sturcture. Translations are not considered in this software. The turbine is modeled as a two-body system consisting of 1) a floating spar hull with tower and 2) the complete rotor-nacel assembly (RNA), the center of mass of which is assumed to be directly over the tower. The complete RNA is assumed to be rotating. The theory underlying this software is based on analytically combining the Euler equations of motion of the RNA with those of the hull and tower assembly. Theoretical details are available in Wang, L. and Sweetman, B., "Simulation of Large-Amplitude Motion of Floating Wind Turbines using Conservation of Momentum" Ocean Engineering, Volume 42, Pg 155-164, March 2012. This work was supported by the National Science Foundation, Division of Power, Controls and Adaptive Networks under Agreement Number PCAN-1133682 Any opinions, findings, and comclusions or recommendations expressed in this material do not necessarily reflect the view of the National Science Foundation.

Programs

Not yet available.

Wind Turbine Motion Simulation using 3-1-3 Sequenced Euler Angles

A time-domain motion simulator in which the rotational dynamics of the structure are computed using Eulers Equations of Motion, based on a 3-1-3 sequence of Euler Angles. Translations are not considered. The turbine is modeled as a two-body system consisting of 1) a floating spar hull with tower and 2) the complete rotor-nacel assembly (RNA), teh center of massof which is assumed to be directly over the tower. The complete RNA is assumed to be rotating. The theory underlying this software is based on analytically combining the Euler equations of motion of the RNA with those of the hull and tower assembly. Theoretical details are available in Sweetman, B. and Wang, L., "Floating Offshore Wind Turbine Dynamics: Large-Angle Motion in Euler-Space" Journal of Offshore Mechanics and Arctic Engineering, OMAE-10-1056. This work was supported by the National Science Foundation, Division of Civil and Mechanical Systems under Agreement Number CMS-0448730. Any opinions, findings, and comclusions or recommendations expressed in this material do not necessarily reflect the view of the National Science Foundation.

Programs

Downlad .tar file of Matlab source code

Hermite Model of Extremes

A software tool that computes any fractile of a distribution described by its first four statistical moment (mean, variance, sckewness and kurtosis) by transforming an equivalent extreme value to or from it's Gaussian equivalent. The theory underlying this software is available in: Choi, M. and Sweetman, B., "The Hermite Moment Model for Highly Skewed Response with Application to Tension Leg Platforms" Journal of Offshore Mechanics and Arctic Engineering, May 2010, Volume 132, Issue 2.

Programs

Download Hermite Model of Extremes Software

Stationarity

Two traditional tests of statistical stationarity have been implemented into a convenient software tool. The software performs a standard runs test and performs a standard reverse arrangements test. Input to the software is a column of numbers which generally represents a measured time-history of a dynamic process and a desired level of confidence that the process is stationary. Output is a confidence level that the process is stationary.

The program is driven by an input command file and produces output to both the screen and to an output file. Sample input, data and output files are available for download.

Reference

Julius S. Bendat and Allan G. Piersol, 1986 , "Random Data: Analysis and Measurement Procedures"

Programs

Package for Windows XP(zip)

Windows XP Executable
Sample Input Command File
Sample Data 1
Sample Data 2
Sample Screen Output
Sample Output File