悬浮流中浮升气泡运动的数值模拟

Numerical simulation of flotation bubble motion in suspension fluid

为了研究气泡在矿浆中的运动规律及寻找气泡的最佳尺寸范围，运用流体体积法（Volume of fluid，VOF）模拟不同初速度和不同初始直径的气泡在不同密度矿浆中的运动过程。结果表明：在不同密度的矿浆中，浮升气泡的最佳尺寸各不相同，随着矿浆密度的增大，浮升气泡的最佳尺寸减小。矿浆密度为1175 kg/m2时，浮升气泡的最佳尺寸为5 mm；矿浆密度为1400 kg/m2时，浮升气泡的最佳尺寸为4 mm；矿浆密度为1600 kg/m2时，浮升气泡的最佳尺寸为3 mm。在实际生产中，矿浆的密度为1175~1400 kg/m2，中等大小（直径为3~4 mm）气泡在运动过程中变形平缓且变形程度小、浮升能力强，故其对矿物粒子的运载能力较强，有利于提高浮选生产的产量和质量。

In order to research the flotation bubble motion law and the best bubble size range under different working conditions, the volume of fluid method （VOF） was applied to simulate the motion of bubbles with different initial velocities and diameters for different ore pulp densities. The results show that the optimal sizes of flotation bubble are different for different ore pulp densities, the best flotation bubble size decreases with the ore pulp density increasing;the best flotation bubble size is about 5 mm when the ore pulp density is 1 175 kg/m2;the best bubble size is about 4 mm when the ore pulp density is 1 400 kg/m2;the best bubble size is about 3 mm when the ore pulp density is 1 600 kg/m2. The ore pulp density is 1175-1400kg/m2 in the actual production, while the medium size bubbles （3-4 mm in size） have gentle deformation with small degree of deformation and big buoyancy lift, which have better capacity to carry mineral particles and effectively improve the quantity and quality in the pulp density with practical mineral flotation.