To get the sustainable society, the hydropower with not only the large but also the small/mini/micro capacities has been paid attention to in the power generation. The cross flow turbine can work effectively at the comparatively low head and/or low discharge, then the runner and the turbine profile has been optimizing. In this paper, the model turbine was prepared in accordance with the traditional design, and the performance and the flow condition were investigated experimentally at the various operating conditions. The hydraulic efficiency is doubtlessly maximal while the guide vane is at the normal/design position, and deteriorates in the lower discharges adjusted by the guide vane. Such deteriorations are brought from the unacceptable flow conditions in the inlet nozzle. To improve the efficiency dramatically in the lower discharge, the guide vane installed in the inlet nozzle was equipped with the current plate, and the fruitful effects of the plate on the efficiency were confirmed experimentally.
 L. Cho, K. Kurokawa, J. Matsui and H. Imamura, “Application of Low Head Cross Flow Turbine to Micro Capacity Hydropower (Simplified Structure and Improved Performances),” JSME Series B, Vol. 67, No. 664, 2001, pp. 222-227. (in Japanese)
 T. Kitahora, M. Inagaki, M. Uchida and S. Ooike, “Influence of Pressure in Runner Chamber on Performance Estimation of Micro-Head Cross Flow Hydraulic Turbine,” Proceedings of Renewable Energy 2010, Yokohama, 31 May-2 June 2010, CD-ROM: O-Sh-4-5.
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