Secondary Flows and Losses in Two Types of Straight Turbine Cascades. Part 1-A: Stator Case

摘要

Some experimental information on secondary flows and on the associated total pressure losses occurring within turbine cascades is given. Part 1 describes the mechanism of production and development of the loss caused by secondary flows in a straight stator cascade with a turning angle of about 65 deg. A full representation of superimposed secondary flow vectors and loss contours is given at fourteen serial traverse planes located throughout the cascade. The presentation shows the mechanism clearly. Distributions of static pressures and of the loss on various planes close to blade surfaces and close to an endwall surface are given to show the loss accumulation process over the surfaces of the cascade passage. Variation of mass-averaged flow angle, velocity and loss through the cascade, and evolution of overall loss from upstream to down stream of the cascade are also given. Part 2 describes the mechanism in a straight rotor cascade with a turning angle of about 102 deg.