The bathymetry of the reservoir is shown in the figure below.
The colours show the depth, where blue is the largest depth, and red is the smallest depth.
The SSIIM model was used for the CFD calculations. The lake was modelled with a strucured grid with hexahedral cells. The grid is seen from above in the figure below:
The velocities in the reservoir for a steady situation witout density variations is shown below. The inflow water velocity is 300 qubic meters/second.
The colours show the horizontal velocity, where blue is the smallest velocity and red is the highest veloctiy
The sediment concentration near the bed for a steady situation witout density variations is shown below. The sediments have an average diameter of 0.04 mm.
The colours show the sediment concentration near the bed, where blue is the smallest concentration and and red is the highest concentration
The turbidity currents in the reservoir was calculated using an inflow sediment concentration of 37 000 ppm, and taking into account the effect of density differences on the water flow field. A time-dependent calculation was done, with a time step of 10 seconds. After 2900 iterations (8 hours), the velocity in the streamwise direction was high close to the bed and a return flow was seen close to the water surface. This is shown on the figures below. Note the main flow direction is from left to right.
Longitudinal profile along centerline of the reservoir (j=6) showing velocities
Longitudinal profile along centerline of the reservoir (j=6) showing velocities, upstream detail
Longitudinal profile along centerline of the reservoir (j=6) showing velocities, detail from the middle of the reservoir
Longitudinal profile along centerline of the reservoir (j=6) showing velocities, detail from downstream part of the reservoir
This project was carried out in cooperation with Oscar Jimenez at Insituto Costarricence de Electricidad, Costa Rica.
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