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In this article, flow and dispersion of pollution in hilly terrain was investigated experimentally in the wind tunnel. A turbulent boundary layer flow was simulated as the approaching flow which passed over the hilly model. Tufts visualization was employed to obtain the wind field of mean flow direction. Methane mixed with pure air was chosen as the tracer for studying stack plume dispersion. Tufts visualization results showed the wind field of mean flow direction which revealed how the winds were flowing over the hilly terrain model for various wind directions. Reversed flows were observed at the region of leeside of main hills or mountains of the terrain model. The plume average height increased with increase in the topography change parameter of the hilly terrain. When varying the topography change parameter of flat terrain into hilly terrain, the plume vertical dispersion parameter increased, accordingly.

In this study, an integral bubble plume model is applied to simulate the behaviors of offshore gas well blowout under seawater. The numerical model simulation results are good in comparison with the field data. The bubble plume radius, upward velocity and buoyancy for different ambient fluid stratification and gas flow rate cases are calculated and investigated. Analysis of the calculated results reveal that: (1) The bubble plume radius increases but terminal rise height decreases when the gas flow rate decreases. (2) Ambient sea water with strong density stratification will inhibit the bubble plume rise and reduce its terminal rise height. (3) Sea water stratification effect on the bubble plume terminal rise height is more significant than that of gas flow rate in several orders of magnitude.

The present study utilized the Lagrangian discrete parcel method to simulate the spreading of an oil spill on the coastal waters. The physical transport processes which include oil slick mechanical spreading, current advection, turbulent diffusion, evaporation, dissolution, and shoreline conditions are considered. Oil slick spreading area as a function of time for different conditions was also investigated. The simulation results are good in comparison with the field observation data. Numerical calculation results show that the whole oil slick splits into small slicks easier for a continuous spill than for an instantaneous spill. With a higher drift velocity, the whole oil slick splits into small slicks more easily.

The VITA (Variable‐Interval Time‐Averaging) technique is employed to detect burst‐events in the turbulent boundary layers for 103