Conventional Axial Flow Turbine Runner Blades Hydraulic Design Methods Research

The distribution of rainfall isn' t even in much of our country. In some season the volume of flow is decreased so much that cannot propel hydraulic turbine, which is a widely problem faced by many propeller turbines. The best measures to resolve the problem is designing a runner with lower specific speed. The new runner must be suited to current speed and channel. For the capacity of propeller turbine is often small, people pay little importance on the transformation of reducing capacity under specified conditions. So, nowadays little research mentioned above has been developed.For the particularity of the designed factors, the author has improved the traditional theory, and has fined an available Method of singular point distribution. At present, no one has developed CAD hydraulic design software of lower specific speed axial flow runner in our country. In general, the design work with traditional measures is done by hand, which cannot meet the needs of the technology and manufacture. So the author has developed a CAD hydraulic design software fit for lower specific speed axial flow runner, which is easily operated by users.The main research work of this paper is as follows:1) Analyzing the main reason of axial flow power station cannot work well under littler volume of flow in some season and putting forward an improving scheme, pointing out the characters of design under abnormal factors.2) Combined with the development of the industry in our country, the abnormal hydraulic design method of propeller turbine is discussed based on present literature, data and experiment results.3) Guided by the design method of software engineering, a suit of hydraulic design software of Lower Specific Speed Axial Flow Runner is programmed by the object-oriented programming language Visual Basic and a straightforward, concise and standard Windows human-computer dialogue interface is designed for the system, which makes the operation of the system very convenient.4) ActiveX Automation technology is adopted as the interface with AutoCAD and the hydraulic drawings are edited, modified by AutoCAD until hydraulic model drawings according with the demand of engineering practice are output.5) To resolve practice problem, the author has designed a lower specific speed axial flow runner for Duowa Power Station through an example.