Wind field simulations at Askervein hill - WindSim

As can be seen on figure 3.17, the inflow n°2 seems not to change the results a lot.
On the contrary, the non equilibrium boundary condition seems to yield unphysical solution
on the lee side (see figure 3.18). This boundary condition seems not to fit the case.
3.4. Turbulence model
In this part, different turbulence models are tested : standard k-ε model, modified k-ε model,
mixing length model and two-scale k-ε model.
The c grid is chosen, boundary condition on the ground is GRND2, inflow is the log law
profile.
A line
2.0
1.5
exp results
k−eps mod
2 scale k−eps
mix length
normalized velocity
1.0
0.5
0.0
500.0 1000.0 1500.0 2000.0 2500.0
distance along A line (m)
Figure 3.17. A line with different models
Figures 3.17, 3.18 and 3.19 : The mixing length model yields rather good results along A line
but underpredicts velocities along AA line. The modified constants in the k-ε model do not
seem to improve the results in comparison with the standard values (is that a mistake in the
simulation parameters ?), whereas the two-scale k-ε model, as expected, slightly improves
results on the lee side, predicting the same results as the k-ε model upwind the hill top.
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