Wind Flow Modeling: choosing between simple and advanced models?
With the more advanced models, computing time can be very large. To keep the runtime manageable the mesoscale NWP model is typically coupled to a microscale model to achieve high spatial resolution. The two major differences between a linear or RANS model compared to a NWP model is that the former is typically run in steady-state mode and without a complete prognostic equation for temperature (i.e. conservation of energy). Therefore, the unsteadiness in the flow and thermal effects are typically not accounted for in linear and non-linear RANS models.
The wind flow models were compared against high-quality observations using 53 meteorological masts from nine project areas in North America and Europe for a total of 144 mast pairs. We will show the accuracy (in terms of RMSE) of wind flow models by terrain complexity, land cover and distance to met mast. In addition to our analysis, we will provide a review of the blind comparison study which included the results from 30 different teams and was presented at the AWEA Wind Resource & Project Energy Assessment workshop in fall 2013.