围油栏前压力垂直结构对油水界面稳定性的影响

Relationship between pressure gradient along the boom and the instability of oil-water interface

油水界面不稳定是围油栏失效的主要原因.该文采用油水二维湍流模型,基于PLIC-VOF(Piecewise Linear Interface Construction-Volume of Fluid)方法模拟油水界面运动,以油水密度比值、水流流速、围油栏吃水深度和油的运动黏度为参数,研究了围油栏前压力梯度的变化及其对油水界面稳定性影响的规律.研究结果表明围油栏前压力垂直结构直接决定了油水界面稳定性;临界压力梯度作为判断油水界面稳定性的标准在多数情况下都是很有效的,但是由于没有考虑运动黏度的影响,当运动黏度小于0.15cm2s-1时,不能再运用临界压力梯度标准判断油水界面稳定性.

The instability of an oil-water interface leads to the boom failure. An oil-water turbulence model based on the PLIC-VOF （Piecewise Linear Interface Construction-Volume of Fluid） method was developed to simulate both the pressure gradient along the face of boom and the movement of oil in water. Altogether four parameters—the specific gravity of the oil,current velocity,boom draft and kinematic viscosity coefficient of the oil—were used to evaluate how the pressure gradient along the boom varies and whether the oil-water interface is stable under different oil,water and boom conditions. It was found that oil-water interface stability is decided by pressure gradient and an instability criterion is predictive in most cases,except when the kinematic viscosity coefficient of the oil is less than 0.15 cm2 s-1.