Numerical characterization of Horizontal Axis Hydrokinetic Turbines Array
Hydrokinetic turbines, similarly to wind turbines, should be placed in
the form of an array to have the potential for electricity production
necessary to connect to the electrical grid and feed it at a commercial scale.
Due to the confined nature of tidal sites, however, the spacing of turbines
in an array of Marine Hydrokinetic (MHK) turbines is much more critical to
the energy production and economic viability of the turbine farm than in
wind energy installations, and needs to be highly optimized. This optimization
process must maximize the efficiency of power generation while minimizing the
capital cost of the infrastructure, the potential environmental effects of the
array and the fatigue load on the turbines' structure. The initial step to
perform this optimization process is to understand the flow field in the array
and how the devices perform while interacting with this complex velocity field.
This initial step also provides an in-depth understanding of the potential
constraints for the array optimization process. A numerical methodology
can then be developed to model the essential physics of the flow field needed
for the array computations, in an time-efficient way compatible with the
optimization of turbine array performance. This numerical methodology can
be used to examine the effect of various constraints in this optimization
process, such as the number of turbines per surface area, the number of
turbine rows, ... .
In this part of my research the Blade Element Model (BEM), one of the models
from the previously developed methodology in the context of the characterization
of a single MHK turbine, is used for the flow field simulation in an array of
turbines. The BEM of several turbines in different spatial configurations and
operating at different set points is implemented to match experimental conditions
in two- and three-turbine arrays in a research flume. The goal of this process
is to further validate the application of the BEM model to turbine wake and
performance characterization in an array.
Ph.D. Dissertation (Ch. 3)