풍력과 조류발전용 수평축 터빈 및 횡류 터빈의 형상설계와 성능평가에 관한 연구

Abstract

The knowledge in the area of fluid dynamics is increasingly being applied to the field of renewable energy to achieve better design of energy extraction devices. Because the expansion of fluid dynamics such a design optimization of the rotor blades is necessary factor to increase the efficiency of the energy extraction devices and to reduce the unit cost of development.

More than 65 countries now have goals for their own renewable energy futures, and are enacting a far-reaching array of policies to meet those goals. More than US$100 billion was lately invested in renewable energy production assets, manufacturing, research, and development. Many renewable technologies and industries have been growing at annual rates of 20 to 60 percent, thereby capturing the interest of the largest global companies and national government agencies.

Currently the most active, competitive and representative research area of the renewable energy resources is wind power. Grafting of the aerodynamics significant achieve progress has already been and wind energy has been developing rapidly, start from 10kW-class small wind turbines now reached MW-class large-scale wind farms.

Republic of Korea, there is no distinct reference for the related design technology of rotor blade of wind turbine. Therefore the optimum design and evaluation of performance is carried out with foreign commercial code softwares. This paper shows in-house code software that evaluates the aerodynamic design of wind turbine rotor blade using blade element-momentum theory (BEMT) and processes that is applied through various aerodynamics theories such as momentum theory, blade element theory, prandtl's tip loss theory and strip theory. This paper presents the results of the numerical analysis such as distribution of aerodynamic properties and performance curves using in-house code POSEIDON.

Just the difference between working fluid, air and water, tidal current energy and wind turbine has significant similarities in generate type. Sea water, which is 832 times denser than air, gives a 2.5 m/s ocean current more kinetic energy than 97 m/s wind

therefore ocean currents have a very high energy density, therefore requiring a smaller device to harness that energy than to harness wind energy. In addition, despite of various benefits with the generate principles, development of tidal current energy significant progress has been slowly compared to wind power generation.

Wherewith, horizontal axis turbine rotor blade developed with aerodynamic is applied for tidal current energy. Recently 3 bladed horizontal axis rotor blade of the highest efficiency was modified for 100kW class HATT which will be installed at real site, mean tidal current 2.3 m/s position nearby Neok-island in the southern part of Korea peninsula. The HATT was adapted for numerical analysis and the compatibility of HATT is verified using a commercial computational fluid dynamics (CFD) code, ANSYS-CFX. This paper presents results of the numerical analysis, such as pressure, streak line, velocity vector and the performance curves with torque data for the inflow of the horizontal axis tidal current turbine (HATT).

Also, among various turbine have been developing with wind energy, cross flow turbine was researched that has a few result of performance analysis for tidal current energy. Therefore, Some potential advantages of ducted and diffuser-augmented current turbine was newly explored. This augmentation channel is designed for generating bi-directionally and a conceptual cross-flow turbine is placed in the augmentation channel. The compatibility of this turbine system is verified using a commercial CFD code, ANSYS-CFX. This paper presents the results of the numerical analysis in terms of pressure, streaklines, velocity vectors and performance curves for 100kW-class cross flow energy integrated type bi-directional tidal current turbine (CEBTT) with augmentation channel.