前弯型叶片叶轮液力透平水力性能研究
发布时间：2019-01-09 13:25
【摘要】：世界经济飞速发展,能源需求随之增长,各国学者纷纷加大了对新能源技术的研究。在化工生产工艺流程以及小水电领域常常使用液力透平回收液体中的能量,目前国内外多数使用离心泵反转用作液力透平。在离心泵反转用作液力透平的工程实践中,现存的主要问题有:高效点处效率偏低,高效工作区范围较小等。分析产生这些问题的原因主要有:其一,反转用作液力透平的离心泵一般是按离心泵的设计方法进行设计与优化的,并未针对反转用作液力透平的使用工况进行设计与优化。当离心泵反转用作液力透平时,蜗壳、叶轮等水力部件不适合液力透平的工况,导致液力透平的效率偏低;其二,反转用作液力透平的离心泵叶轮叶片多数为后弯型,此种叶轮在透平工况下高效区范围窄,当流量变化较大时,液力透平的效率会快速下降;前弯型叶片叶轮液力透平的高效区范围比后弯型叶片叶轮液力透平宽。本课题的主要工作如下:1.对现有后弯型叶片叶轮进行再设计,使用BladeGen设计了比转速为59、107和145的前弯型叶片叶轮液力透平,供后续实验、数值模拟使用。2.通过数值模拟与试验对比,得到一种较为准确模拟前弯型叶片叶轮液力透平的方法。3.通过数值模拟比转速为59、107和145的前弯型叶片叶轮液力透平,掌握了不同比转速的前弯型叶片叶轮液力透平的外特性、流场分布以及水力损失分布等。4.研究了叶片数、包角、叶轮外径以及切割叶轮等对前弯型叶片叶轮液力透平的外特性、流场分布、水力损失的影响。本文的创造性成果有:1.对现有离心泵作透平的后弯型叶轮进行了改型,设计了前弯型叶片叶轮;通过对比实验结果与数值模拟结果,找到了较为准确的数值模拟方法。2.对比转速为59、107和145的前弯型叶片叶轮液力透平进行了数值模拟研究,得到了不同比转速的前弯型叶片叶轮液力透平的外特性曲线,分析流场分布、水力损失分布规律,寻找优化方向。3.对前弯型叶片叶轮的几个主要参数(叶片数、包角和叶轮外径等)进行了数值模拟研究,得到了不同几何参数下的前弯型叶片叶轮液力透平的外特性曲线、流场分布、水力损失分布规律,探讨叶轮几个主要几何参数(叶片数、包角、叶轮外径等)对液力透平水力性能的影响规律,为工程实践提供理论基础。
[Abstract]:With the rapid development of the world economy, the energy demand increases, and scholars from all over the world increase the research on new energy technology one after another. Hydraulic turbine is often used to recover the energy of liquid in the field of chemical production process and small hydropower. At present, most of the centrifugal pumps are used as hydraulic turbine at home and abroad. In the engineering practice of centrifugal pump inversion as hydraulic turbine, the main problems are: low efficiency at high efficiency point, small scope of high efficiency working area, etc. The main reasons for these problems are as follows: first, the centrifugal pump used as hydraulic turbine is generally designed and optimized according to the design method of centrifugal pump, and the design and optimization of the centrifugal pump used as hydraulic turbine is not carried out. When the centrifugal pump is used as hydraulic permeation at ordinary times, the hydraulic components such as volute and impeller are not suitable for the working condition of hydraulic turbine, which leads to the low efficiency of hydraulic turbine. Secondly, the blade of centrifugal pump impeller which is used as hydraulic turbine is mostly back curved type. The efficiency of hydraulic turbine will decrease rapidly when the flow rate changes greatly. The range of high efficient zone of the hydraulic turbine of the forward curved blade impeller is wider than that of the backward curved blade impeller. The main work of this subject is as follows: 1. The hydraulic turbine with specific speed of 59107 and 145is designed by using BladeGen to redesign the existing rear curved blade impeller, which is used for further experiment and numerical simulation. Through the comparison of numerical simulation and test, a more accurate method of simulating the hydraulic turbine of the vane impeller is obtained. Through the numerical simulation of the hydraulic turbine of the forward curved blade impeller with specific speed of 59107 and 145, the external characteristics, the distribution of the flow field and the distribution of the hydraulic loss of the hydraulic turbine of the vane impeller with different specific speeds are mastered. The effects of blade number, enveloping angle, outer diameter of impeller and cutting impeller on the external characteristics, flow field distribution and hydraulic loss of vane impeller were studied. The creative achievements of this paper are as follows: 1. The retroflex impeller of centrifugal pump is modified and the forward curved impeller is designed. By comparing the experimental results with the numerical simulation results, a more accurate numerical simulation method is found. 2. A numerical simulation study on hydraulic turbine of forward curved blade impeller with 59107 and 145 speed is carried out. The external characteristic curve of hydraulic turbine with different specific speed is obtained, and the distribution of flow field and hydraulic loss is analyzed. To find the optimum direction. 3. Numerical simulation of several main parameters (number of blades, enveloping angle and outer diameter of impeller) of forward curved blade impeller is carried out. The external characteristic curve and flow field distribution of hydraulic turbine of forward curved blade impeller under different geometric parameters are obtained. The distribution law of hydraulic loss and the influence of several main geometric parameters of impeller (blade number, envelope angle, outer diameter of impeller etc.) on hydraulic performance of hydraulic turbine are discussed, which provides a theoretical basis for engineering practice.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TH311
[Abstract]:With the rapid development of the world economy, the energy demand increases, and scholars from all over the world increase the research on new energy technology one after another. Hydraulic turbine is often used to recover the energy of liquid in the field of chemical production process and small hydropower. At present, most of the centrifugal pumps are used as hydraulic turbine at home and abroad. In the engineering practice of centrifugal pump inversion as hydraulic turbine, the main problems are: low efficiency at high efficiency point, small scope of high efficiency working area, etc. The main reasons for these problems are as follows: first, the centrifugal pump used as hydraulic turbine is generally designed and optimized according to the design method of centrifugal pump, and the design and optimization of the centrifugal pump used as hydraulic turbine is not carried out. When the centrifugal pump is used as hydraulic permeation at ordinary times, the hydraulic components such as volute and impeller are not suitable for the working condition of hydraulic turbine, which leads to the low efficiency of hydraulic turbine. Secondly, the blade of centrifugal pump impeller which is used as hydraulic turbine is mostly back curved type. The efficiency of hydraulic turbine will decrease rapidly when the flow rate changes greatly. The range of high efficient zone of the hydraulic turbine of the forward curved blade impeller is wider than that of the backward curved blade impeller. The main work of this subject is as follows: 1. The hydraulic turbine with specific speed of 59107 and 145is designed by using BladeGen to redesign the existing rear curved blade impeller, which is used for further experiment and numerical simulation. Through the comparison of numerical simulation and test, a more accurate method of simulating the hydraulic turbine of the vane impeller is obtained. Through the numerical simulation of the hydraulic turbine of the forward curved blade impeller with specific speed of 59107 and 145, the external characteristics, the distribution of the flow field and the distribution of the hydraulic loss of the hydraulic turbine of the vane impeller with different specific speeds are mastered. The effects of blade number, enveloping angle, outer diameter of impeller and cutting impeller on the external characteristics, flow field distribution and hydraulic loss of vane impeller were studied. The creative achievements of this paper are as follows: 1. The retroflex impeller of centrifugal pump is modified and the forward curved impeller is designed. By comparing the experimental results with the numerical simulation results, a more accurate numerical simulation method is found. 2. A numerical simulation study on hydraulic turbine of forward curved blade impeller with 59107 and 145 speed is carried out. The external characteristic curve of hydraulic turbine with different specific speed is obtained, and the distribution of flow field and hydraulic loss is analyzed. To find the optimum direction. 3. Numerical simulation of several main parameters (number of blades, enveloping angle and outer diameter of impeller) of forward curved blade impeller is carried out. The external characteristic curve and flow field distribution of hydraulic turbine of forward curved blade impeller under different geometric parameters are obtained. The distribution law of hydraulic loss and the influence of several main geometric parameters of impeller (blade number, envelope angle, outer diameter of impeller etc.) on hydraulic performance of hydraulic turbine are discussed, which provides a theoretical basis for engineering practice.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TH311
【相似文献】
相关期刊论文 前10条
1 典平鸽;杨孙圣;;叶轮进口宽度对液力透平性能的影响[J];机械设计与研究;2012年02期
2 朱勇更;;叶轮尺寸参数对径流涡轮性能特性的影响[J];国外内燃机车;1973年07期
3 沈天耀;前向叶轮的流动模型及其设计计算方法[J];清华大学学报(自然科学版);1980年02期
4 俞秀民;副叶轮密封的设计计算[J];润滑与密封;1982年03期
5 施卫东,曹卫东,刘厚林,仇宝云,刘小龙;不同叶轮结构型式对污水泵性能的影响[J];农业工程学报;2003年02期
6 耿少娟;聂超群;黄伟光;冯涛;刘克;;不同叶轮形式下离心泵整机非定常流场的数值研究[J];机械工程学报;2006年05期
7 丰镇平,徐进峰,沈祖达;向心透平叶轮进口型线的改型分析[J];工程热物理学报;1990年01期
8 张振山;张艳伟;杨玉敏;马s，
本文编号：2405683
本文链接：https://www.wllwen.com/jixiegongchenglunwen/2405683.html
