Hydrodynamic Shape Design And Performance Evaluation Of Fixed-pitch HAMCT Turbine Wheel

With the increasing depletion of fossil fuels, the ocean is becoming main battlefield of new energy sources exploitation for the world. Marine current energy is an important form of ocean energy, and its exploitation and utilization is of great significance to the energy industry of China. Horizontal Axis Marine Current Turbine (HAMCT) is the main device for converting marine current energy to electrical energy, and one of the core issues of HAMCT design is the design of turbine wheel. Related theories and design methods of HAMCT turbine wheel is currently at the exploratory stage, none of some mature and systematic design theory having formed yet, so the space of innovation in this research field is quite large. The study object of this thesis is fixed-pitch HAMCT turbine wheel, referring to theories and design methods of Horizontal Axis Wind Turbine (HAWT), a new method that is suitable for the design of HAMCT turbine wheel is put forward finally. Then the hydrodynamic shape design and performance evaluation of a 100 kilowatt fixed-pitch HAMCT turbine wheel is accomplished by using the new method. The main work is as follows:(1) Elaborates the backgrounds and significances of the study on HAMCT, and describes the currently status of research and development of HAMCT, also basic design theories that is suitable for the design of HAMCT turbine wheel, such as Blade Element Momentum (BEM) theory, is set forth.(2) Elaborates the basic theories of airfoil profile such as airfoil lift-drag characteristics and stall phenomenon, then the type of airfoil profile for my design is confirmed according to airfoil selection principles and Reynolds of marine current, namely NACA 63-4XX series.(3) FLUENT software is used for 2-D numerical simulation of the airfoil profile. Two-dimensional "C" shaped O-Grid structured grid mesh is brought in, high-quality two-dimensional grid is generated. Then investigate the relationship between simulation data and foreign authoritative experimental data on lift-drag characteristics of the airfoil profile, verified the effectiveness of FLUENT numerical simulation; do the comparison of lift-drag characteristics of the airfoil profile in two different fluid medium, little difference is found; also the influence of thickness on lift-drag characteristics of the airfoil profile is studied, the conclusion is that larger thickness corresponding smaller lift-drag ratio.(4) Make the comparison of Glauert method and Wilson method, to determine the design method of my thesis is mainly referring to Wilson method. Confirm the sea state parameters and the basic parameters of turbine wheel via reviewing the literature and calculations. To accomplish the design of turbine wheel, MATLAB coding is used for the calculations of hydrodynamic shape parameters of turbine blades, such as chord length and twist angle.(5) Pro/E software is used for 3-D parametric modeling of the turbine wheel mentioned above, and hydrodynamic performance evaluation of the turbine wheel is carried out by using a calculation model which bases on BEM theory and combines with Prandtl correction and Glauert correction.