EXPERIMENTAL STUDY ON BLADE POSITIVE CURVING IN TURBINE CASCADE WITH TURNING ANGLE

As contrasted with the experimental study on blade negative curving in turbine cascade with large turning angle,an experimental study of blade positive curving was also carried out under identical conditions.The experimental results show that blade positive curving intensifies the leading edge vortex and the passage vortex in comparison with conventional straight cascade,and increases the bubble separation loss of the leading edge vortex and the viscous dissipation loss of the passage vortex.As a result,the flux capability of the cascade is cut down by 8.8%,the mass flux averaged overall loss coefficient increases by 11.4%,at the same time the outlet conditions of the cascade further deteriorate.