Wells turbine has inherent disadvantages in comparison with conventional turbines: relative low efficiency at high flow coefficient and poor starting characteristics. To solve these problems, the authors propose Wells...Wells turbine has inherent disadvantages in comparison with conventional turbines: relative low efficiency at high flow coefficient and poor starting characteristics. To solve these problems, the authors propose Wells turbine with booster turbine for wave energy conversion, in order to improve the performance in this study. This turbine consists of three parts: a large Wells turbine, a small impulse turbine with fixed guide vanes for oscillating airflow, and a generator. It was conjectured that, by coupling the two axial flow turbines together, pneumatic energy from oscillating airflow is captured by Wells turbine at low flow coefficient and that the impulse turbine gets the energy at high flow coefficient. As the first step of this study on the proposed turbine topology, the performance of turbines under steady flow conditions has been investigated experimentally by model testings. Furthermore, we estimate mean efficiency of the turbine by quasi-steady analysis.展开更多
A twin unidirectional impulse turbine has been proposed in order to enhance the performance of wave energy plant. This turbine system uses two unidirectional impulse turbines and their flow direction is different each...A twin unidirectional impulse turbine has been proposed in order to enhance the performance of wave energy plant. This turbine system uses two unidirectional impulse turbines and their flow direction is different each other. However, the effect of guide vane solidity on the turbine characteristics has not been clarified to date. The performances of a uni- directional impulse turbine under steady flow conditions were investigated experimentally by using a wind tunnel with large piston/cylinder in this study. Then, mean efficiency of the twin impulse turbine in bidirectional airflow has been estimated by a quasi-steady analysis using experimental results in order to investigate the effect of guide vane solidity on the performance.展开更多
文摘Wells turbine has inherent disadvantages in comparison with conventional turbines: relative low efficiency at high flow coefficient and poor starting characteristics. To solve these problems, the authors propose Wells turbine with booster turbine for wave energy conversion, in order to improve the performance in this study. This turbine consists of three parts: a large Wells turbine, a small impulse turbine with fixed guide vanes for oscillating airflow, and a generator. It was conjectured that, by coupling the two axial flow turbines together, pneumatic energy from oscillating airflow is captured by Wells turbine at low flow coefficient and that the impulse turbine gets the energy at high flow coefficient. As the first step of this study on the proposed turbine topology, the performance of turbines under steady flow conditions has been investigated experimentally by model testings. Furthermore, we estimate mean efficiency of the turbine by quasi-steady analysis.
文摘A twin unidirectional impulse turbine has been proposed in order to enhance the performance of wave energy plant. This turbine system uses two unidirectional impulse turbines and their flow direction is different each other. However, the effect of guide vane solidity on the turbine characteristics has not been clarified to date. The performances of a uni- directional impulse turbine under steady flow conditions were investigated experimentally by using a wind tunnel with large piston/cylinder in this study. Then, mean efficiency of the twin impulse turbine in bidirectional airflow has been estimated by a quasi-steady analysis using experimental results in order to investigate the effect of guide vane solidity on the performance.
