上喷式矿井排风热回收装置内液滴运动模型及其优化计算

发布时间：2018-11-19 21:08

【摘要】：为了减小常见下喷式装置风吹水损失大的问题,设计了上喷式矿井排风热回收装置。通过液滴受力及运动分析,将上喷式液滴的运动划分为2个阶段。根据牛顿第二定律,建立了简化的液滴动量方程;在该方程的基础上,结合运动阶段划分,得到临界条件下的力平衡关系式;利用该式,在10个不同相对速度下,得到了上喷式与下喷式的保证液滴不被吹飞的临界直径。应用变量替换,将液滴动量方程变换为液滴运动距离的微分式;继而,根据液滴及空气之间的雷诺数组合,导出了液滴最大上升高度的5个积分计算式。应用这些积分式,数值计算了不同迎面风速、液滴粒径及液滴初速度下,上喷式中液滴最大上升高度、下喷式中液滴最大下降高度。对比计算结果,相比下喷式,上喷式具有节水、液滴选择范围宽和低耗高效的优势。
[Abstract]:In order to reduce the problem of large loss of air blowing water in common down-air injection units, a heat recovery device for upper jet type mine exhaust air was designed. According to the analysis of droplet force and motion, the motion of upper spray droplet is divided into two stages. According to Newton's second law, a simplified equation of droplet momentum is established, on the basis of the equation and combined with the division of motion stages, the force balance relation under critical conditions is obtained. By using this formula, the critical diameter of the upper jet and the lower jet can be obtained at 10 different relative velocities to ensure that the droplets will not be blown away. By variable substitution, the droplet momentum equation is transformed into the differential equation of the droplet's moving distance, and then, according to the Reynolds number combination between the droplet and the air, five integral formulas for the maximum rising height of the droplet are derived. By using these integral equations, the maximum rising height of droplet in the upper jet and the maximum drop in the droplet in the lower jet are calculated numerically under different head-on wind speed, droplet diameter and initial velocity of the droplet. Compared with the lower jet, the upper jet has the advantages of saving water, wide choice range of droplets and low consumption and high efficiency.
【作者单位】：湖南大学土木工程学院;
【基金】：国家自然科学基金项目(51134005,U1361118)
【分类号】：TD72

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