Actual Total Cost reduction of commercial CFD modelling tools for Wind Resource Assessment in complex terrain

In this paper, new automated processes for applying the commercial Computational Fluid Dynamics (CFD) tools ANSYS Fluent and ANSYS CFX to wind modelling in complex terrain are developed with the goal of decreasing the Actual Total Costs (ATC) related to planning wind energy projects. Simulations are carried out at the complex terrain site St¨otten in southern Germany using ANSYS Fluent and ANSYS CFX, and the ATCs related to the simulations estimated. The simulation setup and post-processing effort are identified as having the highest effect on the ATC, and therefore the automated processes focus on reducing the effort of these tasks. Simulations of the same test site are carried out with the new automated processes, and compared to the manual processes as well as to an industry-standard tool, WindSim. The new automated tools are found to reduce the ATC of this case by a factor of 12 for Fluent and seven for CFX, to approximately half the value of WindSim. All three simulations show similar deviations compared to measurements and therefore these results are comparable. It should be noted that these results are highly specific to this case, and the absolute cost-saving values cannot be directly transferred to other cases. Nevertheless, it can be concluded that these new processes have significantly reduced the Actual Total Cost and are likely to have a large effect on the choice of the most cost-effective model for a given wind energy project. On-going work involves quantifying the effect of these cost savings on the choice of most appropriate model for this simulation site and further comparing the results to measurements.