Category 4 Benchmark Problem

Problem Description

This test case was defined at the "Third Computational Aeroacoustics (CAA) Workshop on Benchmark Problems". The aim is to determine the amplitudes of the reflected and transmitted acoustic modes due to an incoming vorticity wave impinging on 24 flat plates in an annulus. The basic geometry is shown in the table below. The amplitude of the incoming vorticity wave is set to 10 percent of the steady axial flow velocity and the amplitude is assumed to be constant in the radial direction. The full description of the test case can be found in the report.

Geometry 3D Annulus Number of Blades 24 Incoming Circumferential Wave Number 16 Hub to Tip Ratio 0.5 Gap to Chord Ratio at Tip 1.0 Steady Axial Mach number 0.5

Results

• Acoustic Modes


• Acoustic Mode Amplitude Table


• Wave Plots