In Japan, there still are many undeveloped hydro-power sites of low head which provide the output less than 100kW. To utilize them efficiently and effectively, the authors have developed a micro tubular turbine under the wide range operation. As the further study, we treat the following issues in this paper: one is the flow mechanism of the increase in hydraulic efficiency with the serial arrangement of tubular turbines, which is aimed to widen their application for higher head sites. And the other is the investigation of cavitation characteristics of the micro tubular turbine associated with the cam-combination. An interesting finding is that there is suitable cam-combination for the cavitation characteristic, which is better than that of the on-cam condition. It is possible to increase the discharge up to 12% by the proposed cam-combination.
抄録全体を表示