引流隔膜泵内部流动特性研究

发布时间：2018-11-22 12:31

【摘要】：近来海上溢油事故频繁发生,各国越来越重视溢油的防治与回收。鉴于海上溢油回收作业方式以及污油的特性,污油输送泵应具有结构紧凑、重量轻、处理量大、可输送含固体颗粒或粘性较大的流体,并具有空载运转和连续运转、过载不会烧毁的特点。隔膜泵工作原理适于溢油回收,但国产隔膜泵结构笨重、处理量低,国外技术封锁严重。因此,开发适合中国国情、价格低、处理量相对较大的新型隔膜泵已经成为目前亟待解决的问题。应用引流原理的隔膜泵体积效率有很大提高,更适合海上污油输送。论文根据流体力学的基本原理,建立了引流隔膜泵的理论模型,并对微分方程组进行了求解,得到了理论引流泵内部流体的流动规律。分析表明,引流泵的工作过程分为推进流动和引流流动两个阶段,在推进流动阶段,活塞排出流体速度大于排出管道中流体速度,部分流体储存于缓冲罐中,随着活塞速度的降低,缓冲罐中的流体又被释放出来,继续推动流体加速;在引流流动阶段,外界流体在排出管道中流体惯性力的作用下继续被输送。用速度源项模拟缓冲罐的作用,并基于In-Form方法和动物体方法实现了阀门的开关功能,编写了物体运动的MOF文件,最终形成了一套引流隔膜泵的数值计算方法。应用该方法对一理论引流泵进行了数值模拟,验证了引流流动的存在,并且表明在理论条件下引流泵的体积效率达到了200%以上。同时,计算流量曲线与理论推导所得曲线大致相同,验证了数值研究方法的合理性。应用同样的数值研究方法,对一实际引流隔膜泵的内部流动进行了数值模拟,发现在引流作用下泵的体积效率为127%,但内部流动明显不对称,主流偏向于排出管道一侧,泵内流动损失较大。对称结构引流隔膜泵内部流动的数值模拟表明,内部流动损失明显减小,引流效果有所增强。论文研究结果对引流隔膜泵的优化设计有一定的理论指导价值。
[Abstract]:Recently, oil spill accidents occur frequently at sea, and more countries pay attention to prevention and recovery of oil spills. In view of the mode of recovery of oil spills at sea and the characteristics of the contaminated oil, the pump should be compact in structure, light in weight, large in handling capacity, capable of transporting fluids containing solid particles or large viscosity, and have no-load operation and continuous operation, The feature that overload does not burn. The working principle of diaphragm pump is suitable for oil spill recovery, but the domestic diaphragm pump is heavy in structure, low in handling capacity and severely blocked by foreign technology. Therefore, the development of a new type of diaphragm pump, which is suitable for China's national conditions, low price and relatively large handling capacity, has become an urgent problem to be solved. The volume efficiency of diaphragm pump based on drainage principle has been greatly improved, which is more suitable for oil transport on the sea. According to the basic principle of fluid mechanics, the theoretical model of the drainage diaphragm pump is established, and the differential equations are solved, and the internal fluid flow law of the theoretical drainage pump is obtained. The analysis shows that the working process of the drainage pump can be divided into two stages: the propulsion flow and the drainage flow. In the propulsion flow stage, the velocity of the piston discharge fluid is higher than that of the discharge pipe, and some of the fluid is stored in the buffer tank. As the piston speed decreases, the fluid in the buffer tank is released again, and the fluid continues to accelerate. In the drainage flow stage, the external fluid continues to be transported under the action of the fluid inertia force in the drainage pipeline. The function of buffer tank is simulated by velocity source term, and the switch function of valve is realized based on In-Form method and dynamic object method. The MOF file of object motion is compiled, and a set of numerical calculation method of drainage diaphragm pump is finally formed. The numerical simulation of a theoretical drainage pump is carried out by using this method, which verifies the existence of the drainage flow and shows that the volume efficiency of the drainage pump is over 200% under the theoretical conditions. At the same time, the calculated flow curve is approximately the same as the calculated curve, which verifies the rationality of the numerical method. By using the same numerical method, the internal flow of a practical drainage diaphragm pump is numerically simulated. It is found that the volume efficiency of the pump under the drainage is 127, but the internal flow is obviously asymmetric, and the main flow is inclined to one side of the drain pipe. The flow loss in the pump is large. The numerical simulation of the internal flow of the symmetrical structure drainage diaphragm pump shows that the internal flow loss is obviously reduced and the drainage effect is enhanced. The results of this paper have certain theoretical guiding value for the optimal design of drainage diaphragm pump.
【学位授予单位】：中国石油大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH323

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