隔舌对双吸泵性能影响及其改型设计研究
发布时间：2018-09-04 11:07
【摘要】：单级双吸中开式离心泵广泛应用于水利灌溉工程、城市给排水、工业循环水、跨流域调水等领域，是一种重要的水力机械，其运行特性对泵站工程造价、运行及维护等具有重要影响。对双吸泵运行特性进行深入研究，不仅具有理论意义，而具有重要工程实用价值。由于双吸泵一般流量较大，扬程较高，所需配用功率大，是一种耗能较大的设备。因此，使用单位对双吸泵的效率有较高的要求，而国内目前所生产的双吸泵效率普遍不太高，尤其是一些低比转速的双吸泵，其效率都比较低，有的泵效率达不到70%。所以提高双吸泵的效率，节能降耗尤为重要。随着国家在今后对水利建设方面投资力度的加大，双吸泵的使用量将进一步的增加，因此对双吸泵性能的改进，对于泵产品节能降耗具有重要意义。 近年来，计算流体力学（CFD）技术已经广泛并成功的运用于泵的设计和分析计算中，在科研和工程领域有着广泛的应用。为了准确了解泵内过流部件对其性能的影响，本文基于泵设计理论，借助CFD软件对双吸泵过流部件进行了研究分析计算。 对于双吸泵的主要过流部件压水室（蜗壳）和半螺旋吸入室，本文主要针对蜗壳隔舌和半螺旋吸入室隔舌（鼻端）进行了分析研究。通过CFD软件，对蜗壳隔舌在不同的隔舌安放角时，对其不同工况下进行了定常分析计算；并对泵在不同隔舌安放角时，在设计工况点进行了非定常数值模拟分析；对不同的吸入室隔舌，在不同工况下进行了定常分析。 通过对数值计算结果的分析发现，当蜗壳的隔舌使用不同隔舌安放角时，泵的性能均有变化，尤其在偏大流量工况，隔舌安放角对泵的影响较明显，其影响主要由于隔舌安放角变化引起的隔舌间隙的改变对泵的影响，另外还有蜗壳喉部面积的变化，隔舌顶部的冲击损失对泵性能的影响相对较小；对于吸入室隔舌，隔舌距离泵轴的距离改变，对泵的性能也有一定的影响，在大流量工况影响较明显，，其影响主要由于隔舌对液流的作用及吸入室内速度不同部分液流的相互作用。对于本文使用的模型泵，蜗壳内隔舌处隔舌安放角的大小和吸入室内隔舌距离泵轴的距离大小，这些参数均有一个较好的值。吸入室隔舌离泵轴的距离大小应根据不同的泵来确定其值。 本文的分析结果表明，对双吸泵内过流部件的深入研究，有利于泵性能的提高，对泵产品的节能降耗和市场竞争力的提升有一定的帮助。
[Abstract]:Single stage and double suction open centrifugal pump is widely used in water conservancy and irrigation engineering, urban water supply and drainage, industrial circulating water, trans-basin water transfer and so on. Operation and maintenance have important impact. It is not only of theoretical significance, but also of great practical value to study the operating characteristics of double suction pumps. The double suction pump is a kind of energy consuming equipment because of its high flow rate, high head and high power consumption. Therefore, the efficiency of the double suction pump is very high, but the efficiency of the double suction pump produced in our country is generally not very high, especially for some low specific rotational speed double suction pump, its efficiency is relatively low, some pump efficiency is less than 70. So it is very important to improve the efficiency of double suction pump and save energy and reduce consumption. With the increase of national investment in water conservancy construction in the future, the use of double suction pump will be further increased, so the improvement of double suction pump performance is of great significance for energy saving and consumption reduction of pump products. In recent years, computational fluid dynamics (CFD) technology has been widely used in pump design, analysis and calculation, and has been widely used in scientific research and engineering fields. In order to accurately understand the influence of the flow passing parts in the pump on its performance, based on the pump design theory and with the help of CFD software, this paper studies and calculates the flow passing parts of the double suction pump. The pressure chamber (volute) and semi-helical suction chamber are the main parts of double suction pump. This paper mainly analyzes and studies the diaphragm (nasal end) of volute septum and semi-helical suction chamber. Through the software of CFD, the unsteady analysis and calculation of the volute diaphragm tongue under different working conditions are carried out, and the unsteady numerical simulation analysis is carried out at the design working condition when the pump is placed at different angle of diaphragm tongue. A steady analysis of different suction chamber septum was carried out under different working conditions. Through the analysis of the numerical results, it is found that the performance of the pump varies with the use of different tongue separation angles in the volute, especially in the condition of large flow rate, the influence of the angle of setting the tongue on the pump is obvious. The influence is mainly due to the change of the gap between the tongue and the pump caused by the change of the angle of setting the tongue, and the change of the throat area of the volute. The impact loss at the top of the diaphragm has relatively little effect on the performance of the pump. The change of the distance between the pump shaft and the tongue diaphragm has a certain effect on the pump performance, which is more obvious in the large flow condition, mainly due to the effect of the tongue separation on the liquid flow and the interaction of the different parts of the fluid flow in the suction chamber. For the model pump used in this paper, these parameters have a good value, such as the angle of the tongue septum in the volute and the distance between the suction chamber and the pump shaft. The distance between the suction chamber and the pump shaft should be determined according to the pump. The results of this paper show that the deep study of the overflowing parts in the double suction pump is beneficial to the improvement of pump performance and to the improvement of energy saving and consumption reduction of pump products as well as the promotion of market competitiveness.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH311
本文编号：2221899
[Abstract]:Single stage and double suction open centrifugal pump is widely used in water conservancy and irrigation engineering, urban water supply and drainage, industrial circulating water, trans-basin water transfer and so on. Operation and maintenance have important impact. It is not only of theoretical significance, but also of great practical value to study the operating characteristics of double suction pumps. The double suction pump is a kind of energy consuming equipment because of its high flow rate, high head and high power consumption. Therefore, the efficiency of the double suction pump is very high, but the efficiency of the double suction pump produced in our country is generally not very high, especially for some low specific rotational speed double suction pump, its efficiency is relatively low, some pump efficiency is less than 70. So it is very important to improve the efficiency of double suction pump and save energy and reduce consumption. With the increase of national investment in water conservancy construction in the future, the use of double suction pump will be further increased, so the improvement of double suction pump performance is of great significance for energy saving and consumption reduction of pump products. In recent years, computational fluid dynamics (CFD) technology has been widely used in pump design, analysis and calculation, and has been widely used in scientific research and engineering fields. In order to accurately understand the influence of the flow passing parts in the pump on its performance, based on the pump design theory and with the help of CFD software, this paper studies and calculates the flow passing parts of the double suction pump. The pressure chamber (volute) and semi-helical suction chamber are the main parts of double suction pump. This paper mainly analyzes and studies the diaphragm (nasal end) of volute septum and semi-helical suction chamber. Through the software of CFD, the unsteady analysis and calculation of the volute diaphragm tongue under different working conditions are carried out, and the unsteady numerical simulation analysis is carried out at the design working condition when the pump is placed at different angle of diaphragm tongue. A steady analysis of different suction chamber septum was carried out under different working conditions. Through the analysis of the numerical results, it is found that the performance of the pump varies with the use of different tongue separation angles in the volute, especially in the condition of large flow rate, the influence of the angle of setting the tongue on the pump is obvious. The influence is mainly due to the change of the gap between the tongue and the pump caused by the change of the angle of setting the tongue, and the change of the throat area of the volute. The impact loss at the top of the diaphragm has relatively little effect on the performance of the pump. The change of the distance between the pump shaft and the tongue diaphragm has a certain effect on the pump performance, which is more obvious in the large flow condition, mainly due to the effect of the tongue separation on the liquid flow and the interaction of the different parts of the fluid flow in the suction chamber. For the model pump used in this paper, these parameters have a good value, such as the angle of the tongue septum in the volute and the distance between the suction chamber and the pump shaft. The distance between the suction chamber and the pump shaft should be determined according to the pump. The results of this paper show that the deep study of the overflowing parts in the double suction pump is beneficial to the improvement of pump performance and to the improvement of energy saving and consumption reduction of pump products as well as the promotion of market competitiveness.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH311
【引证文献】
相关期刊论文 前1条
1 肖若富;王娜;杨魏;姚志峰;王福军;;复合叶轮改善双吸式离心泵空化性能研究[J];农业机械学报;2013年09期
本文编号：2221899
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