Scaling of the thermal mixing processes within the lower plenums of VHTR designs

Graduation date: 2006The Very High Temperature Reactor (VHTR) design was one of six designs chosen\ud for development under the Generation IV initiative. Thermal mixing of the coolant at\ud the exit of the reactor has been a common concern for VHTR reactor designs.\ud Thermal mixing processes are commonly investigated through the use of scaled\ud experimental models. Accurate scaling methods are essential for designing\ud experimental facilities that accurately reproduce the thermal mixing processes of the\ud VHTR design under investigation. A scaling method that is based upon a two-equation\ud turbulence closure model is developed in this paper. Numerical studies\ud performed verify that this scaling method correctly identifies the similarity parameters\ud of the k-ε turbulence closure model and preserves the turbulent processes within the\ud flow