<P> Axial flow turbomachines - When the path of the through - flow is wholly or mainly parallel to the axis of rotation, the device is termed an axial flow turbomachine . The radial component of the fluid velocity is negligible . Since there is no change in the direction of the fluid, several axial stages can be used to increase power output . </P> <P> A Kaplan turbine is an example of an axial flow turbine . </P> <P> In the figure: </P> <Ul> <Li> U = Blade velocity, </Li> <Li> V = Flow velocity, </Li> <Li> V = Absolute velocity, </Li> <Li> V = Relative velocity, </Li> <Li> V = Tangential or Whirl component of velocity . </Li> </Ul>

Why is the francis turbine classified as a radial-flow device