Study On The Influence Of Waves On The Dynamic Process Of Spilled Oil Submerging

With the frequent occurrence of oil spills,oil has become one of the major pollutants at sea.The danger of submerged oil in offshore oil pollution is becoming more and more serious.Due to its complicated formation mechanism,it is difficult to track and observe the existing technology,which leads to traceability,prevention and hazard assessment.Therefore,the research on submerged oil is very urgent.Factors affecting oil spills include oil body properties such as(oil density,oil viscosity and changes in the properties affected by weathering evaporation),natural factors such as temperature,wave action(the greatest and complex effects of wave action)and human factors such as artificial spray the dispersant.In order to study the formation mechanism of submerged oil under the influence of wave action and other factors,and to find favorable conditions for constructing the oil spill submerged model.In this paper,four kinds of Bohai crude oils YYH,YYS,SJH and SLY were selected as the research objects.The Jieante dispersant was selected and the baffle flask and medium wave tank were used to simulate the regular wave and breaking wave under natural sea conditions.The behaviors of four oil samples under different wave action and dispersant content were discussed.The stationary time period was designed to be 10 min to observe the stability characteristics of the submerged oil droplets of different oil samples.The analysis was carried out under different experimental conditions.The variation of particle size on different spatial locations is used to further explore the formation mechanism of submerged oil.Through the analysis and summary,the following conclusions are obtained:(1)The wave action is divided into entrainment and fragmentation.The initial entrainment is significant.After a period of accumulation,the fracture is dominant;the entrainment is positively correlated with oil viscosity and wave strength.Under certain conditions,the dispersant the addition also promotes the entrainment of the waves;When the wave entrainment effect is significant,after reaching the stabilization time of 120 min,the submerging rate is above 98%and the produced oil droplets have a large particle size.(2)The dispersant has a complicated influence on the oil spill potential.The dispersant can not only promote the oil film breakage,but also increase the mutual solubility of the oil droplets and increase the aggregation floating behavior;the oil film that is re-floating from the dispersant is not easy to break down;the use of dispersant It is necessary to match the oil viscosity and to consider the coupling with the wave,otherwise the change in the submerging rate is abnormal.(3)Stable submerged oil formation conditions are:broken into tiny oil droplets(low viscosity oil 75 ?m?85 ?m)or oil droplet density(high viscosity oil 95 ?m?100 ?m);continuous wave breaking effect;the dispersing agent is added when the wave breaking action is dominant.(4)When the wave breaking process is dominant,it is found that the submerging rate has a good linear relationship with the oil droplet size;there is also a good linear relationship between the submerging rate of the stable submerged oil drop and its particle size after standing.Based on this,the oil spill rate-particle size model can be constructed.Under different wave strength conditions,the experimental data of the submerging rate-dispersant-viscosity,particle size-dispersant-viscosity were obtained,and the a ln(v)+b type equation was obtained.