A Study of the Ability of Meteodyn WT to Replicate Measurements around Steep Hills Using Wind Tunnel Data from the ‘RUSHIL’ Experiment

Comparisons are made between Meteodyn WT (MWT) and wind tunnel measurements from the three RUSHIL test cases that represent hills of increasing steepness. The two steeper cases are of interest; in one the flow on the lee side is close to separation (Hill 5), for the other the flow has clearly separated (Hill 3). Although it is well known that WAsP 8.3 (WP) cannot predict separation, its predictions are included to represent the current industry standard. Both models agree well with mean wind speeds measured upstream of the Hill 5 crest. MWT gives significantly better but not good agreement upstream of the Hill 3 crest, where WP significantly over-predicts the speed-up. Downstream, MWT predictions are closer to measurements, but predict a smaller separation bubble on Hill 3, due to limitations of the turbulence model. A practical viewpoint requires improved modelling to have only a minimal impact on computational resource requirements.

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