[egge24]

Hi,

I´m modelling an array of 3 marine current turbines using a porous jump boundary condition. The domain is a rectangular channel with 650. length, 400m width and 100m depth. Hub height is 30m from the bottom. Porous jump parameters are the same for the 3 turbines and are set to represent a thrust coeff. = 0.8. Parameter values are:

- Face permeability, m²: 1e+10
- Porous medium thickness, m: 0.5
- Pressure Jum Coeff. C2, 1/m: 25

Solution converges after 260 iterations. Follows a figure showing velocity magnitude contours at hub height horizontal plane.

When I generate the reports for Volumetric and Mass Flow Rates for each turbine, I get negative values for side turbines and a positive value for center turbine. Values are as follows:

Volumetric Flow Rate (m3/s)
-------------------------------- --------------------
(Up) Turbine-1 -37.982517
(Center) Turbine-2 90.828041
(Down) Turbine-3 -38.849861
---------------- ------------------------
Net 13.995665

Mass Flow Rate (kg/s)
-------------------------------- --------------------
(Up) Turbine-1 -38932.082
(Center) Turbine-2 93098.742
(Down) Turbine-3 -39821.109
---------------- -------------------------
Net 14345.555

But surface velocity integral are very similar for each disk.

Does anyone knows why this is happening and how can I obtain real values?

Thanks in adavance.