Design of Two-dimensional Channels with Prescribed Velocity Distributions Along the Channel Walls

by John D. Stanitz

1952

Methods of solution by Green's function are developed for the design of two-dimensional unbranched channels with prescribed velocities as a function of arc length along the channel walls. The methods apply to incompressible and linearized compressible, nonviscous irrotational flow. One numerical example is presented for an accelerating elbow shape obtained from the solution by Green's function is the same as that obtained from a solution by relaxation methods for the same prescribed conditions. The time required for the calculations is considerably less for solutions by Green's functions.

Application of a Channel Design Method to High-solidity Cascades and Tests of an Impulse Cascade with 90° of Turning

by John D. Stanitz, Leonard J. Sheldrake

1952

A technique is developed for the application of a channel design method to the design of high-solidity cascades with prescribed velocity distributions as a function of arc length along the blade-element profile. The technique applies to both incompressible and subsonic linearized compressible (ratio of specific heats equal to -1.0), nonviscous, irrotational, fluid motion. An impulse cascade with 90 degree turning was designed for incompressible flow and was tested at the design angle of attack over a range of downstream Mach number from 0.2 to choke flow. To achieve good efficiency, the cascade was designed for prescribed velocities with maximum allowable blade loading according to limitations imposed by considerations of boundary-layer separation.