Modelling the 3D flow in the Sava river at the entrance to the inflow channel of nuclear power plant Krško and comparison with measurements

摘要

A hydro-electric power plant (HEPP) Brežice will be built 7 km downstream of the Nuclear power plantudKrško (NPPK). This will cause a 3 m rise of the water level, which will change the hydraulic and thermaludconditions at the entrance of the cooling water to the inflow channel. The project task was to simulate theudvelocity field and sediment transport in the future conditions at his location, and to simulate thermaludconditions in the entire Brežice reservoir. As the vertical velocity components in the vicinity of the inflowudare of the same order of magnitude as the horizontal components, the velocity field is “fully 3D”. As theudapplied model PCFLOW3D is in the “quasi 3D” form, we performed measurements of the velocities in theudSava River near the inflow to the channel. During the verification of the model we found that the model gives good results for the flow upstream of the inflow section, while near the inflow the results are lessudreliable. We are currently preparing a “fully 3D” version of the model. The present model showed that in theudfuture conditions the sediment inflow into the inflow channel will not change significantly. Verification ofudthe thermal module had already been carried out in 1995 and 1998 on the reservoir Vrhovo in both summerudand in winter conditions. It was shown that the model can well simulate the thermal conditions.