The three-dimensional boundary layer on a rotating helical blade

Abstract

The development of a laminar boundary layer on a twisted helical blade is described. An appropriate co-ordinate system is developed in which the boundary-layer equations have a relatively simple form. The choice of blade geometry and the free-stream conditions result in a constant-pressure flow. This permits the flow to be considered the analogue, in a rotating frame, of the zero-pressure-gradient flat-plate boundary layer in a stationary frame. The boundary-layer equations are solved using a double series expansion in powers of distance from the leading edge and the cosine of the blade twist angle. Chordwise and spanwise velocity profiles are calculated. The variation in the skin friction coefficients is calculated as a function of position on the blade.

The Effect of Reaction on Compressor Performance

“…rotor stator upon the blade stagger angle and rotational speed. Later studies by Banks & Gadd (1963), Morris (1981) and Miyake & Fujita (1974) observed similar results to Horlock & Wordsworth. All of these early studies rely on simple analytical models of radial boundary layers, which were validated in simple, idealised, rotating disc experiments.…”

Viscous flow around a propeller-shaft configuration with infinite-pitch rectangular blades

“…Most of the studies pertain to boundarylayer development and are restricted to laminar flow and idealized geometries. 2 Only one study has considered practical geometries and flow conditions. 3 In general, these methods suffer due to the inaccuracy of the pressure distributions predicted by inviscid-flow methods and are not easily extendable into the wake.…”