Environmental assessment technique for nuclear power plants using wind tunnel experiments. Evaluation of effective stack height for release speed ratio

Wind tunnel experiments are used to study the air pollution from nuclear power plant stacks. Many experiments have been conducted on a terrain model using a scale of one to a few thousands set in the wind tunnel. Effective stack height is defined to explain the terrain effect compared with a flat plate. In experiments, the tracer gas is released at an arbitary velocity in the down wind direction from a modified Γ-shaped stack. For more accurate environmental assessment, release speed ratios of tracer gas to wind speed near the stack is changed from 1 to 4 times. The study found that release speed ratio is not significant for the evaluation of effective stack height. (author)