Oscillating Turntable for the Measurement of Unsteady Aerodynamic Phenomena

54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

Piatak

2013

Self Cite

The Benchmark SuperCritical Wing (BSCW) wind tunnel model served as a semi-blind testcase for the 2012 AIAA Aeroelastic Prediction Workshop (AePW). The BSCW was chosen as a testcase due to its geometric simplicity and flow physics complexity. The data sets examined include unforced system information and forced pitching oscillations. The aerodynamic challenges presented by this AePW testcase include a strong shock that was observed to be unsteady for even the unforced system cases, shock-induced separation and trailing edge separation. The current paper quantifies these characteristics at the AePW test condition and at a suggested benchmarking test condition. General characteristics of the model's behavior are examined for the entire available data set.

“…8 The model is shown mounted in the wind tunnel during testing on the OTT, Figure 2. The data obtained during the OTT testing is the data primarily examined in this paper.…”

Section: Wind Tunnel Model and Facilitymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Experimental data from the Benchmark SuperCritical Wing wind tunnel test on an oscillating turntable

54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

Piatak

2013

Self Cite

“…All data to be used in this study was obtained at Dynamic data was obtained for the BSCW by oscillating the model in a pitching motion about the 30% chord using an oscillating turntable. 22 Unforced system quantities for this configuration were calculated as the time-averaged (mean) values obtained without excitation. To better capture the information, maximum and minimum values that occurred during the unforced system time records were also included in the comparison data set.…”

Section: Vb Benchmark Supercritical Wing Bscwmentioning

confidence: 99%

“…The AePW was held April [21][22]2012 in Honolulu Hawaii, in association with the 53 rd AIAA/ASME /ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, and sponsored by the AIAA Structural Dynamics Technical Committee (SDTC). The workshop website contains the presentations from this meeting and other information required to begin analyses of the workshop configurations.…”

mentioning

confidence: 99%

Overview of the Aeroelastic Prediction Workshop

51st AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition

Chwalowski²,

Florance³

et al. 2013

The Aeroelastic Prediction Workshop brought together an international community of computational fluid dynamicists as a step in defining the state of the art in computational aeroelasticity. This workshop's technical focus was prediction of unsteady pressure distributions resulting from forced motion, benchmarking the results first using unforced system data. The most challenging aspects of the physics were identified as capturing oscillatory shock behavior, dynamic shock-induced separated flow and tunnel wall boundary layer influences. The majority of the participants used unsteady Reynolds-averaged Navier Stokes codes. These codes were exercised at transonic Mach numbers for three configurations and comparisons were made with existing experimental data. Substantial variations were observed among the computational solutions as well as differences relative to the experimental data. Contributing issues to these differences include wall effects and wall modeling, nonstandardized convergence criteria, inclusion of static aeroelastic deflection, methodology for oscillatory solutions, post-processing methods. Contributing issues pertaining principally to the experimental data sets include the position of the model relative to the tunnel wall, splitter plate size, wind tunnel expansion slot configuration, spacing and location of pressure instrumentation, and data processing methods.

“…The second configuration utilized was the NASA Benchmark Supercritical Wing (BSCW), which was tested in the NASA Langley TDT in 2000. This data set was acquired for a "rigid" rectangular planform similar to the RSW that was sidewall-mounted to a large splitter plate assembly and oscillated in pitch via the TDT Oscillating Turntable (OTT), 9 exhibiting a strong shock and boundary-layer-induced separated flow at a moderate angle of attack. The third configuration considered for AePW extended the unsteady aerodynamic prediction to a weakly-coupled aeroelastic test case involving a more complex geometry: the HIgh REynolds Number AeroStructural Dynamics (HIRENASD) Project configuration.…”

Section: Introductionmentioning

confidence: 99%

Lessons learned in the selection and development of test cases for the Aeroelastic Prediction Workshop: Rectangular Supercritical Wing

51st AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition

Chwalowski²,

Wieseman³

et al. 2013

The Aeroelastic Prediction Workshop brought together an international community of computational fluid dynamicists as a step in defining the state of the art in computational aeroelasticity. The Rectangular Supercritical Wing (RSW) was chosen as the first configuration to study due to its geometric simplicity, perceived simple flow field at transonic conditions and availability of an experimental data set containing forced oscillation response data. Six teams performed analyses of the RSW; they used Reynolds-Averaged Navier-Stokes flow solvers exercised assuming that the wing had a rigid structure. Both steady-state and forced oscillation computations were performed by each team. The results of these calculations were compared with each other and with the experimental data. The steady-state results from the computations capture many of the flow features of a classical supercritical airfoil pressure distribution. The most dominant feature of the oscillatory results is the upper surface shock dynamics. Substantial variations were observed among the computational solutions as well as differences relative to the experimental data. Contributing issues to these differences include substantial wind tunnel wall effects and diverse choices in the analysis parameters.