高比速度可動翼軸流水車における損失解析 : 第3報, ランナ内の摩擦損失と摩擦係数

抄録

This third report deals with friction losses in adjustable blade runners for axial-flow hydroturbines. A method is proposed to extract the friction coefficient for the runner loss from the measured performance characteristics of bulb turbines. As a result of the loss analysis for two model bulb turbines based on the above method under a wide range of runner vane setting angles and wicket gate openings, an algorithm is presented for computing the friction loss in a runner using the well-established friction coefficient for a flat plate with the same Reynolds number and surface roughness as the blade at the root mean square radius.