Studies on the Characteristics of Radial-Flow Nozzles : (2nd Report, Theoretical Analysis of Inward Flow)

Abstract

The inward flow characteristics of radial-flow nozzles are studied by the similar procedure to the 1st Report. As a parameter, R=Vh²/νr₂ should be used to calculate velocity distributions in the clearance, pressure losses, etc., where r₂ is the outer radius of a nozzle and V is a radial mean velocity at r₂. When R is over 5.42, boundary layers cannot fill up the clearance, and if R is less than 5.42, the velocity distribution in the clearance becomes perfectly parabolic, that is, Poiseuille flow will be established. In either case, the thickness of the boundary layer reduces to zero at the center of the nozzle. Therefore, the pressure loss of the nozzle should be expressed by one of the three different equations according to the combination of R and the diameter ratio of the nozzle.