【作者】 苗长山；

【导师】 李继志； 李增亮；

【作者基本信息】 中国石油大学 ， 机械设计及理论， 2007， 博士

【摘要】 螺旋轴流式多相泵是用于油田多相混输生产的一项新技术,针对该泵的研究开发现在已经成为一大热点。本文首先回顾了泵的水力设计、叶片设计理论及泵内流场数值计算的研究现状,明确了多相泵研究中亟待解决的几个问题:缺乏足够的理论基础,设计方法急需改进等。本文采取的技术路线是理论、设计、实验及数值计算相结合,即首先研究泵的工作理论与混输机理,继而以理论为基础指导设计,给出一种设计方法,然后以实验与数值计算对工作理论与设计方法进行检验与修正。具体内容包括:⑴较系统地进行了多相混输泵增压单元工作理论与混输机理的研究,分析了混输泵的外特性,首次建立了泵特性参数、混输能力与结构参数、运行参数和混合液参数的关系,并导出了相关式,为今后方便正确的设计多相泵增压单元提供理论依据;⑵在理论研究的基础上,初步形成了混输泵增压单元结构参数的一种新的设计方法,用以指导泵的子午面设计;⑶基于上述理论,针对均匀流模型,采用准三维反问题的研究思路,以速度矩作为控制参数,导出了混输泵叶型的速度梯度方程,并给出了增压单元叶片型状的反问题设计方法;针对双流体模型,采用准三维正问题的研究思路,分别推导出气相与液相在混输泵中的运动方程,提出一种对混输泵增压单元内流场进行准三维数值计算的方法。并通过具体实例验证了以上两种研究思路所提出的设计方法的可行性;⑷依据上述给出的增压单元内流场准三维正问题的数值模型,并引用多目标遗传算法,首次对混输泵叶片型状进行了优化设计研究。通过对多目标优化设计结果的对比分析,结合混输能力与效率,提出了一种折衷的设计方案:该方案是在效率不低于初始设计要求的条件下混输能力最高的一种设计结果;同时分析了满足不同设计目标的叶片型状的变化趋势,此趋势对今后叶片型状的设计具有一定的指导意义。⑸利用实验与数值计算对工作理论与设计方法进行验证。结合多相泵的实验结果,研究找出一种对增压单元内流场进行数值分析的方法,利用该方法研究多相泵增压单元内气液两相的流动规律,模拟多相泵的特性参数,对多相泵增压单元的结构参数进行优化,并根据数值分析的结果,对增压单元的基础工作理论与设计方法进行检验与修正。更多还原

【Abstract】 As a new technology used for multiphase product in oil field, R&D on helico-axial multiphase pump become a hot topic nowadays.This paper discussed the present research progress of multiphase pump, such as the current situation of hydraulic design for axial pump, the design theory for vane and the numerical calculation for interior flow field. Some problem which should be resolved urgently was proposed, including lack of perfect theory basis, the improvement on design method and so on.Combined with theory, design, experiment, and numerical calculation, work theory of multiphase pump was firstly discussed, and then based on which, the design method was presented. Finally the theory and design method was verified by finite element calculation.Main contents as follows were researched:⑴Theory of compress units for multiphase pump and mechanism of multiphase transportation were conducted systemically, external characteristic of multiphase pump was analyzed. In addition, the relationship between characteristic parameter, multiphase transportation capability and structural parameter, operating parameter, mixed liquid parameter was put forward firstly, and then the related formula was raised, which can provide theory basis for the design of multiphase pump;⑵On the basis of theory research, this paper presented a new design method of the structural parameter for compress unit, as a reference to the design of meridian plane.⑶According to the inverse theory, taking inlet velocity torque as controlled variable, formula was deduced to calculate the velocity gradient of meridian plane, design method of vane shape in compress unit was provided; Meanwhile, according to quasi-three dimensional direct theory, gas and liquid equation running in the multiphase pump was also deduced separately. And a method to carry on the quasi-three dimensional numerical calculation of interior flow field was proposed, which provided basis for the vane shape optimization with multi-objective genetic algorithm. The feasibility of both methods was verified by experiments.⑷With the theory of multi-objective genetic algorithm, Optimization of vane shape in compress unit was carried on. According to the comparison analysis of multi-objective optimization, combined with the multiphase transportation capability and efficiency of multiphase pump, a trade-off design method was proposed, which obtained the best multiphase capability while the efficiency is not lower than the primary requirement. While, the variable tendency of vane shape to fulfill different objective was analyzed and proved to be instructive for the further study.⑸Working theory and design method developed here was proved by numerical calculation and experiments. With the result of lab experiments for multiphase pump, a method to do numerical analysis on the flow field of compress unit was developed, which researched on the flowing rule of gas and liquid in compress unit, simulated the characteristics of multiphase pump and optimized the structural parameter of compress unit. Finally, the working theory and design method of compress unit were improved and optimized according to the numerical analysis result.更多还原