상용 CFD코드를 이용한 파력발전용 직접구동터빈의 유동특성에 관한연구

Abstract

Clean and renewable energy technologies using ocean energy give us non-polluting alternatives to fossil fuel and nuclear-fueled power plants to meet establishment of countermeasures against global warming and growing demand for energy. Among the ocean energy resources, wave power takes a growing interest because of its enormous amount of potential energy in the world. Therefore, various types of wave power system to capture the energy of ocean waves have been developed. The effect of wave is very important and are among the factors for pivotal point that causes effect directly on turbine for wave power generation.

In this research, CFD is used to examine the reciprocating flow of wave tank application before experimentation is done in an actual wave tank to analyze the effect of these wave. As a result, CFD could be applied to the flowing examination before going through reciprocating flow in an actual wave tank.

There are three purposes of the paper:

The first purpose of this study is to investigate the reciprocating flow of the wave tank, which is embodied by a commercial CFD analysis with various water level in the water tank to investigate the effect of the water level on the fluid flow in the water tank.

The second purpose is to investigate the performance of a direct drive turbine using a commercial CFD code and compare the results with the experiments.

The final purpose is to investigate the performance and internal flow characteristics of a Savonius type direct drive turbine under a real sea wave conditions using a commercial CFD code. Optimum turbine location was also determined using vector analysis.

There was about 5% pressure error between CFD analysis and the experimental results. Experimentally 3% expected force was put through manual performance tests and was compared with CFD analysis. Results showed average power obtained through experiment is 20.77W and CFD is 19.19W.

The average power for 3 blade savonius rotor and 5 blade savonius rotor was 7.21kW and 10.33kW respectively. The turbine efficiency obtained for 3 blade savonius rotor was 14.8% and 5 blade savonius rotor had an efficiency of 21.46%.