Characteristics extraction of a turbulent diffusion state for quick trace-back estimation of the diffusion source

When a severe accidents occurs and hazardous substance which damages the environment and public health is emitted into the atmosphere, it is necessary to pinpoint the source of diffusion and to take remedial measures immediately. In order to develop a method of source location, we proposed and tested presumption strategy based on two kinds of experimental results of turbulent diffusion. The spatial distribution of turbulent velocity and concentration fluctuation was acquired by PIV/PLIF simultaneous measurement. Thereby, we tried to extract features which characterize a distance from a source which is useful to locate the source position from the position of observation.The next experiment was PLIF time series aquisition. This experimental record gave us concentration information which has high spatial and temporal resolution. Using these data, we examined two kinds of source presumption methods. One estimates the source position from instantaneous observation in wide area; the other estimated short time statistical observation at limited positions. We compared these performances and considered their validity.