Dispersion Prediction Model for Instantaneous Release of Hazardous Chemicals under Variable Wind Conditions

A modified Gaussian puff model, which is applicable to multiple changes of wind direction and wind speed, is put forward based on the coordinate transformation for the instantaneous release of hazardous chemicals. In addition, a specific implementation method of the model is discussed. Furthermore, the velocity correction is applied to the modified model. The trajectory of the puff center which represents puff motion is analyzed by the linear and quadratic velocity correction methods respectively. It is depicted that the trajectory of puff motion is smooth and the smooth transition sections exist after the change of wind direction and wind speed based on the velocity correction method, showing good agreement with the real conditions.