Measurements of the Flowfield Interaction Between Tandem Cylinders

Summary of the Tandem Cylinder Solutions from the Benchmark problems for Airframe Noise Computations-I Workshop

“…The results with the trip (denoted as C2 Trip, open symbols) have less negative Cp values at the suction peaks in better agreement with the computational results. It should be noted that the participants were not provided with the data for the downstream cylinder tripped until after the workshop, although the BART data 5 was available in the literature. The Cp comparison for the simulations that did not employ the S-A DDES model are shown in Fig.…”

“…Experiments by Jenkins et al 3,4 and Neuhart et al 5 have been performed in the Basic Aerodynamic Research Tunnel (BART) at NASA Langley Research Center, providing steady surface pressures, detailed off-surface measurements of the flow field using Particle Image Velocimetry (PIV), hot-wire measurements in the wake of the downstream cylinder and unsteady surface pressure data. The BART is a subsonic, atmospheric wind tunnel used to investigate the fundamental characteristics of complex flow fields (see Fig.…”

CFD-CAA Coupled Calculations of a Tandem Cylinder Configuration to Assess Facility Installation Effects

“…Such a simplified configuration constitutes an ideal test case for investigating the physics of aerodynamic noise associated with component interaction as well as validating high-fidelity numerical prediction tools for similar sources of noise in actual aircraft undercarriage systems. To this end, extensive experimental data has been [8][9][10][11] and compared to the results of 3-D, unsteady CFD computations 12,13 . Despite the favorable comparison between the measured and computed spectra, a legitimate concern existed about some of the obvious differences occurring between the installed TC configuration that had been tested and the simplified configuration that was computed.…”

Numerical investigation of tandem-cylinder noise reduction using plasma-based flow control

“…Mean flow quantities and vortex-shedding frequencies showed reasonable agreement with experiment for both values of cylinder spacing. More recently, the experimental database for the tandem-cylinder configuration was expanded as reported by Neuhart et al (2009). This study included measurements of fluctuating pressure on the downstream cylinder with high azimuthal resolution, high-resolution PIV measurement of the dynamics of the separating shear layer, as well as the influence of boundary layer trips on both upstream and downstream cylinders.…”