Numerical Analysis Seminars: ANALYSIS OF UNSTEADY FLOWS PAST HORIZONTAL AXIS WIND TURBINE AIRFOILS BASED ON HARMONIC BALANCE COMPRESSIBLE NAVIER-STOKES EQUATIONS WITH LOW-SPEED PRECONDITIONING
11 March 2011 15:15 in CG85
This paper presents the numerical models underlying the
implementation of a novel harmonic balance compressible Navier-Stokes
solver with low-speed preconditioning
for wind turbine unsteady aerodynamics.
The numerical integration of the harmonic balance equations is based on
a multigrid iteration, and, for the first time,
a numerical instability associated
with the use of such an explicit approach in this context
is discussed and resolved.
The harmonic balance solver with low-speed preconditioning is well
suited for the analyses of several unsteady periodic low-speed flows,
such as those encountered in horizontal axis wind turbines.
The computational performance and the accuracy of the technology being
developed are assessed by computing the flow field past two sections
of a wind turbine blade in yawed wind with both the time- and
frequency-domain solvers. Results highlight that the harmonic balance
solver can compute these periodic flows more than 10 times faster
than its time-domain counterpart, and with an accuracy comparable
to that of the time-domain solver.
Contact David.Bourne@durham.ac.uk for more information