DNS 1-6 Statistical Data: Difference between revisions

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The pressure coefficient contour on the bottom surface is reported in [[Lib:DNS 1-6 statistical#figure13|Fig. 13]].
The pressure coefficient contour on the bottom surface is reported in [[Lib:DNS 1-6 statistical#figure13|Fig. 13]].
Due to the problem geomertry, a favourable pressure gradient is generated in front of the wing profile resulting in a reduction of <math>C_{p}</math> (blue area).
Due to the problem geometry, a favourable pressure gradient is generated in front of the wing profile resulting in a reduction of <math>C_{p}</math> (blue area).
This reduction attenuates moving away from the airfoil, but it is still appreciable along the lateral boundaries, i.e., <math>\max{(C_{p,lateral})}=-0.15</math>.
This reduction attenuates moving away from the airfoil, but it is still appreciable along the lateral boundaries, i.e., <math>\max{(C_{p,lateral})}=-0.15</math>.
Accordingly, although small, a blockage effect on the flow due to the lateral boundaries is obtained.
Accordingly, although small, a blockage effect on the flow due to the lateral boundaries is obtained.
As expected for a flow in the incompressible regime (here <math>Ma=0.078</math>), the maximum value of <math>C_{p}</math> is close to 1.
As expected for a flow in the incompressible regime (here <math>Ma=0.078</math>), the maximum value of <math>C_{p}</math> is close to 1.


[[Lib:DNS 1-6 statistical#figure14|Fig. 14]] shows the time averaged dimensionless wall shear stress above the flat plate.
[[Lib:DNS 1-6 statistical#figure14|Fig. 14]] shows the time averaged dimensionless wall shear stress on the floor.
The aforementioned favourable pressure gradient in front of the airfoil induces a flow acceleration, which is the main cause of the increase of the wall shear stress.
The favourable pressure gradient in front of the airfoil induces a flow acceleration, which is the main cause of the increase of the wall shear stress. Downstream the wing, in the wake region, the traces of the horseshoe vortexes are clearly visible. Vortices are also clearly visible by the streamlines at selected planes shown in [[Lib:DNS 1-6 statistical#figure15|Fig. 15]].
Downstream the wing profile, in the wake region, a "double tail" behaviour of the displayed quantity is clearly visible and is generated by the presence of the horseshoe vortex.
This becomes evident extracting streamlines at selected planes, see [[Lib:DNS 1-6 statistical#figure15|Fig. 15]].


<div id="figure13"></div>
<div id="figure13"></div>

Revision as of 18:20, 24 February 2023


Front Page

Description

Computational Details

Quantification of Resolution

Statistical Data

Instantaneous Data

Storage Format

Statistical data

In this section the relevant statistical data for the flow around the wing-body junction computed with MIGALE is given. The reported data is the one mentioned in Table 1 of the list of desirable quantities (PDF).

The data is available as:

  • In .vtu (ASCII) format for statistical data.
  • In .csv (text) format as vertical profiles at various locations.

Volume data

Volumetric data of the statistics are provided here. For more information regarding the stored quantities and the storage format, please refer to the storage format guidelines.

The available files are:

Surface data

Surface data of the statistics are provided here. For more information regarding the stored quantities and the storage format, please refer to the storage format guidelines.

The available files are:

The pressure coefficient contour on the bottom surface is reported in Fig. 13. Due to the problem geometry, a favourable pressure gradient is generated in front of the wing profile resulting in a reduction of (blue area). This reduction attenuates moving away from the airfoil, but it is still appreciable along the lateral boundaries, i.e., . Accordingly, although small, a blockage effect on the flow due to the lateral boundaries is obtained. As expected for a flow in the incompressible regime (here ), the maximum value of is close to 1.

Fig. 14 shows the time averaged dimensionless wall shear stress on the floor. The favourable pressure gradient in front of the airfoil induces a flow acceleration, which is the main cause of the increase of the wall shear stress. Downstream the wing, in the wake region, the traces of the horseshoe vortexes are clearly visible. Vortices are also clearly visible by the streamlines at selected planes shown in Fig. 15.

DNS1-6 Wing-body junction bottom wall pressure coefficient.png
Figure 13: Wing-body junction. Contour of pressure coefficient on the bottom surface for


DNS1-6 Wing-body junction bottom wall averaged wall shear stress.png
Figure 14: Wing-body junction. Contour of averaged dimensionless wall shear stress on the bottom surface for


DNS1-6 Wing-body junction bottom streamlines.png
Figure 15: Wing-body junction. Streamlines at selected planes, i.e., symmetry plane and cross section planes at and , superimposed on contour of averaged dimensionless wall shear stress


Profile data

Profile data have been extracted from the symmetry plane at different streamwise locations () and made dimensionless with respect to reference quantities (, ). The data stored in each file are:

  • vertical location
  • average velocity components
  • Reynolds stress components
  • turbulent kinetic energy

Profiles at selected streamwise locations are reported in Fig. 16.

profile_midplane_-0.45.csv
profile_midplane_-0.40.csv
profile_midplane_-0.35.csv
profile_midplane_-0.30.csv
profile_midplane_-0.25.csv
profile_midplane_-0.20.csv
profile_midplane_-0.15.csv
profile_midplane_-0.10.csv
profile_midplane_-0.05.csv
profile_midplane_-0.01.csv
Table 4: Wing-body junction. Profiles on symmetry plane at different streamwise locations


DNS1-6 Wing-body junction y u.png
DNS1-6 Wing-body junction y v.png
DNS1-6 Wing-body junction y Rexx.png
DNS1-6 Wing-body junction y Reyy.png
DNS1-6 Wing-body junction y Rezz.png
DNS1-6 Wing-body junction y k.png
DNS1-6 Wing-body junction y Reyx.png
Figure 16: Wing-body junction. Profiles at symmetry plane at different stremwise locations


Contour data

Contour data of the averaged velocity components and , the three normal stresses , and , the turbulent kinetic energy , and the shear stress in the symmetry plane are provided in Fig. 17. As the region depicted is in front of the leading edge, it is visible the effect of the horse-shoe vortex: while the streamwise component of the velocity becomes negative above the horizontal solid wall, the normalwise one presents a large negative region close to the leading edge. This results in a clockwise rotating vortex. Within this vortex the Reynolds stresses as well as the turbulent kinetic energy show the maximum intensity. Moreover, looking more in detail, it is possible to notice the presence of a tiny vortex in anticlockwise rotation clinging to the leading edge of the wing, near the wing-body junction. All contours are normalized with respect to the reference quantities.

DNS1-6 Wing-body junction midplane averaged velocity x.png
DNS1-6 Wing-body junction midplane averaged velocity y.png
DNS1-6 Wing-body junction midplane Reynolds stress xx.png
DNS1-6 Wing-body junction midplane Reynolds stress yy.png
DNS1-6 Wing-body junction midplane Reynolds stress zz.png
DNS1-6 Wing-body junction midplane TKE.png
DNS1-6 Wing-body junction midplane Reynolds stress yx.png
Figure 17: Wing-body junction. Contours of average velocity compoents, Reynolds normal stresses, turbulent kinetic energy and Reynolds shear stress at symmetry plane





Contributed by: Francesco Bassi (UNIBG), Alessandro Colombo (UNIBG), Francesco Carlo Massa (UNIBG), Michael Leschziner (ICL/ERCOFTAC), Jean-Baptiste Chapelier (ONERA) — University of Bergamo (UNIBG), ICL (Imperial College London), ONERA

Front Page

Description

Computational Details

Quantification of Resolution

Statistical Data

Instantaneous Data

Storage Format


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