CFD calculations - STEAG

CFD calculationsComputer-based simulation of fluid flow, combustion, heat andmass transfer in power plantswww.steag-energyservices.com1

Heat removal from HAW casks in storage facilitiesWe perform calculations for heat removal from high level radioactive waste (HAW) casksin interim storage facilities. The calculations are performed in the scope of design anddimensioning of these facilities in order to meet thermal criteria. Similar calculations arecarried out for high-level liquid radioactive waste (HLLW) vitrification facilities.HAW casks stored in interim storage facilities generatethermal power due to radioactive decay. The heat removalfrom the facilities is realized by natural ventilation based onconvective cooling mechanisms. Ambient air flows into thefacility through inlets on the side of the building. The air isheated up by convective and radiative heat transfer thatcomes from the HAW casks and leaves the facility throughair outlets located on the roof.Based on numerical heat transfer models, calculations areperformed in order to determine surface and air temperatures.In order to minimize occurring pressure losses, emphasisis placed on the dimensioning of built-in components inthe inlet and outlet ducts, i.e. protective gratings, barriersand louvers. Additionally, concepts to optimize the storingposition configuration of the HAW casks inside the storagefacilities are evaluated.Successfully completed projects have been carriedout for various facilities in Germany and Switzerland:· Interim storage facilities at Unterweser, Grohndeand Brokdorf Power Plant (E.ON)· Interim storage facilities at Brunsbüttel and KruemmelPower Plant (Vattenfall)· Interim storage facilities at Lingen Power Plant (RWE)· Interim storage facilities at Obrigheim Power Plant (EnBW)· Central Swiss Storage Facility (ZWILAG)· Karlsruhe HLLW Vitrification Plant (VEK)2Pathlines of the convection-driven flowthrough an HAW interim storage facility,colored by temperature