波浪破碎下油滴粒径分布理论模型研究

On theoretical models for oil droplets size distribution under the influence of surface wave breaking

海上溢油在波浪破碎的情况下经常会形成油滴,本文讨论了油滴形成的可能机制,根据量纲分析瑞利法建立了油滴卷入率与能量耗散率、卷入深度等破碎统计物理量的关系。基于量纲分析Π定理并根据毛细数、无量纲卷入时间与粘度比的实验关系,导出了油径谱的理论模型。初步结果表明,理论谱斜率-2.29与观测谱斜率-2.3符合良好,剪切率、表面张力、油滴半径、油和水的黏度等因素是影响油滴总数的主要原因。

Marine oil spill often forms oil droplets in stormy conditions..Based on the dimensional analysis Rayleigh method,the relationship is established between entrainment rate of oil droplet and statistical physical quantities such as the energy dissipation rate,intrusion depth et al.An expression of size spectrum of oil droplets is derived based onΠtheorem and relationship between capillary number,the dimensionless intrusion time and viscosity ratio. Preliminary results show that the slope of the derived spectrum is-2.29,which agrees well with the measured slope-2.3 in laboratory.Shear rate,surface tension,droplet radius,oil and water viscosity is the main factors con-trolling the total number of the oil droplets.