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Fixing some typos and adding a small explanation for the MARKER_INLET_TURBULENT for the SA model #141

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2 changes: 1 addition & 1 deletion _data/vandv.yml
Original file line number Diff line number Diff line change
Expand Up @@ -12,6 +12,6 @@
- swbli
- LM_transition

- title: Incompressbile Flow
- title: Incompressible Flow
vandv:
- SANDIA_jet
12 changes: 9 additions & 3 deletions _docs_v7/Markers-and-BC.md
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Expand Up @@ -131,18 +131,24 @@ MARKER_FAR= (farfield)
| --- | --- |
| `RANS`, `INC_RANS`, | 7.3.0 |

The turbulence boundary conditions do not have a `MARKER_` keyword for the SA Turbulence model but can instead be set for inlet and freestream boundaries using the keyword:
The turbulence boundary conditions have a `MARKER_INLET_TURBULENT` keyword for the Turbulence models. For the SA turbulence model, ratio of turbulent to laminar viscosity can be provided at each inlet as follows:

```
MARKER_INLET_TURBULENT= (inlet_marker1, NuFactor1, inlet_marker2, NuFactor2, ...)
```

If 'MARKER_INLET_TURBULENT' is not provided in the .cfg file, SU2 will filled up the markers with the freestream option:

```
FREESTREAM_NU_FACTOR= 3
```

Conversely, for the SST turbulence model, it is possible to provide a 'MARKER_INLET' where turbulence intensity and turbulent-to-laminar ratio can be provided at each inlet as follows:
Similarly, for the SST turbulence model, turbulence intensity and turbulent-to-laminar ratio can be provided at each inlet as follows:

```
MARKER_INLET_TURBULENT= (inlet_1, TURBULENCEINTENSITY_1, TURB2LAMVISCRATIO_1 , inlet_2, TURBULENCEINTENSITY_1, TURB2LAMVISCRATIO_1 ,..)
```
If 'MARKER_INLET_TURBULENT' are not provided in the .cfg file, SU2 will filled up the markers with the freestream options:
If 'MARKER_INLET_TURBULENT' is not provided in the .cfg file, SU2 will filled up the markers with the freestream options:

```
FREESTREAM_TURBULENCEINTENSITY= 0.05
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -131,11 +131,11 @@ MU_CONSTANT= 1.1102E-05, 1.8551E-05
MIXING_VISCOSITY_MODEL = WILKE
```

The Species transport is switched on by setting `KIND_SCALAR_MODEL= SPECIES_TRANSPORT`. For the mass diffusivity, the following models are available `DIFFUSIVITY_MODEL= CONSTANT_DIFFUSIVITY, CONSTANT_SCHMIDT, UNITY_LEWIS, CONSTANT_LEWIS` , where `CONSTANT_DIFFUSIVITY` is the default model. For the first two, a constant value must be specified in the.cfg file for all species, as it is done in the species transport tutorial [Inc_Species_Transport](/tutorials/Inc_Species_Transport/). For the UNITY_LEWIS, no values must be provided because the diffusivity is computed using the mixture thermal conductivity, density and heat capacity at constant pressure; for more information, please see $^{3}$. For highly diffusive gases, such as hydrogen, the `CONSTANT_LEWIS` option could be used. For this option, the Lewis numbers of the N-1 species for which a transport equation is being solved must be provided as a list using the option `CONSTANT_LEWIS_NUMBER= Le_1, Le_2, ..., Le_N_1`. Finally, for turbulent simulations, the turbulent diffusivity is computed based on the `SCHMIDT_NUMBER_TURBULENT`. For reference, please consult [the respective theory](/docs_v7/Theory/#species-transport).
The Species transport is switched on by setting `KIND_SCALAR_MODEL= SPECIES_TRANSPORT`. For the mass diffusivity, the following models are available `DIFFUSIVITY_MODEL= CONSTANT_DIFFUSIVITY, CONSTANT_SCHMIDT, UNITY_LEWIS, CONSTANT_LEWIS` , where `CONSTANT_DIFFUSIVITY` is the default model. For the first two, a constant value must be specified in the.cfg file for all species, as it is done in the species transport tutorial [Inc_Species_Transport](/tutorials/Inc_Species_Transport/). For the UNITY_LEWIS, no values must be provided because the diffusivity is computed using the mixture thermal conductivity, density and heat capacity at constant pressure; for more information, please see $$^{3}$$. For highly diffusive gases, such as hydrogen, the `CONSTANT_LEWIS` option could be used. For this option, the Lewis numbers of the N-1 species for which a transport equation is being solved must be provided as a list using the option `CONSTANT_LEWIS_NUMBER= Le_1, Le_2, ..., Le_N_1`. Finally, for turbulent simulations, the turbulent diffusivity is computed based on the `SCHMIDT_NUMBER_TURBULENT`. For reference, please consult [the respective theory](/docs_v7/Theory/#species-transport).

Finally, for the SST model, it is possible to provide the intensity and turbulent-to-laminar viscosity ratios per inlet. For this option, we use the following structure: `MARKER_INLET_TURBULENT= (inlet_1, TurbIntensity_1, TurbLamViscRatio_1, inlet_2, TurbIntensity_2, TurbLamViscRatio_2, ...)`.

As final remarks, the option `SPECIES_USE_STRONG_BC` is advised to be set to `NO` when the convective scheme for species and turbulent are `CONV_NUM_METHOD_SPECIES= BOUNDED_SCALAR` and `CONV_NUM_METHOD_TURB= BOUNDED_SCALAR`, respectively. When `SCALAR_UPWIND` is used in both cases, the `SPECIES_USE_STRONG_BC` is advised to be switched to `YES` to enforce boundary conditions and improve convergence for this convective scheme. The convective scheme `BOUNDED_SCALAR` will be further explained in the section [Convective-Schemes](/docs_v7/Convective-Schemes/).
As final remarks, the option `MARKER_SPECIES_STRONG_BC` is advised to not to be used when the convective scheme for species and turbulent are `CONV_NUM_METHOD_SPECIES= BOUNDED_SCALAR` and `CONV_NUM_METHOD_TURB= BOUNDED_SCALAR`, respectively. When `SCALAR_UPWIND` is used in both cases, the `MARKER_SPECIES_STRONG_BC` is advised to be used to enforce boundary conditions and improve convergence for this convective scheme. This can be used with the following structure `MARKER_SPECIES_STRONG_BC= (marker1, marker2, ....)`. The convective scheme `BOUNDED_SCALAR` will be further explained in the section [Convective-Schemes](/docs_v7/Convective-Schemes/).

Likewise, `SPECIES_CLIPPING= NO` is only recommended when the option `SCALAR_UPWIND` is used. The option `BOUNDED_SCALAR` performs well without using the clipping option.

Expand All @@ -152,7 +152,6 @@ SPECIFIED_INLET_PROFILE= NO
%
INC_INLET_TYPE= VELOCITY_INLET VELOCITY_INLET
MARKER_INLET= ( inlet_gas, 300, 5.0, 0.0, 0.0, 1.0, inlet_air, 300, 5.0, 0.0, 0.0, 1.0 )
SPECIES_USE_STRONG_BC= NO
MARKER_INLET_SPECIES= (inlet_gas, 1.0, inlet_air, 0.0 )
%
MARKER_INLET_TURBULENT= (inlet_gas, 0.05, 10, inlet_air, 0.05, 10)
Expand Down
8 changes: 3 additions & 5 deletions _vandv/SANDIA_jet.md
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Expand Up @@ -8,9 +8,9 @@ permalink: /vandv/SANDIA_jet/
| `INC_RANS` | 7.5.0 | Sem Bosmans |


The details of the 2D Axisymmetric, Nonpremixed, Nonreacting, Variable Density, Turbulent Jet Flow are taken from [Sandia National Laboratories database](https://tnfworkshop.org/data-archives/simplejet/propanejet/)$$^{1},^{2}$$.
The details of the 2D Axisymmetric, Nonpremixed, Nonreacting, Variable Density, Turbulent Jet Flow are taken from [Sandia National Laboratories database](https://tnfworkshop.org/data-archives/simplejet/propanejet) $$^{1},^{2}$$.

By comparing the results of SU2 simulations case against the experimental data, as well as OpenFOAM simulation results $$^{3}$$ (and MFSim $$^{4}$$), we can build a high degree of confidence that the composition-dependent model is implemented correctly in combination with the SST turbulence model. Therefore, the goal of this case is to validate the implementation of the composition-dependent model in SU2.
By comparing the results of SU2 simulations case against the experimental data, as well as OpenFOAM simulation results $$^{3}$$ (and MFSim $$^{4}$$), we can build a high degree of confidence that the composition-dependent model is implemented correctly in combination with the SST turbulence model. Therefore, the goal of this case is to validate the implementation of the composition-dependent model in SU2.

## Problem Setup
The problem consists of a turbulent propane jet mixing into coflowing air. The schematic overview of this problem is given in the figure below:
Expand Down Expand Up @@ -137,8 +137,7 @@ The comparisons in the figures demonstrate good agreement with the experimental
<img src="/vandv_files/SANDIA_jet/images/YD0_rho.png" alt="Mean density along Jet Centerline" />
</p>

The experimental results for the mean density are given in Sandia’s database, but these are directly computed from the mixture fraction by making use of the ratio between the density of propane and air. The ratio that is being used for this purpose is 1.6 $$^{2}$$, whereas the expected ratio is lower. The higher density ratio used in the post-processing of the experimental data results in a wider
density range across the domain, which can partly explain the differences between the experimental data and the numerical results on the density along the jet centerline. Note that the spreading rate of a jet is independent of the initial density ratio $$^{2}$$.
The experimental results for the mean density are given in Sandia’s database, but these are directly computed from the mixture fraction by making use of the ratio between the density of propane and air. The ratio that is being used for this purpose is 1.6 $$^{2}$$, whereas the expected ratio is lower. The higher density ratio used in the post-processing of the experimental data results in a wider density range across the domain, which can partly explain the differences between the experimental data and the numerical results on the density along the jet centerline. Note that the spreading rate of a jet is independent of the initial density ratio $$^{2}$$.

<p align="center">
<img src="/vandv_files/SANDIA_jet/images/Residuals_convergence.png" alt="Residuals Convergence for the Turbulent Jet Mixing" />
Expand All @@ -147,7 +146,6 @@ density range across the domain, which can partly explain the differences betwee
---

### References

$$^{1}$$ R.W. Schefer, "Data Base for a Turbulent, Nonpremixed, Nonreacting, Propane-Jet Flow", tech. rep., Sandia National Laboratories, Livermore, CA, 2001.

$$^{2}$$ R.W. Schefer, F.C. Gouldin, S.C. Johnson and W. Kollmann, "Nonreacting Turbulent Mixing Flows", tech. rep., Sandia National Laboratories, Livermore, CA, 1986.
Expand Down
5 changes: 5 additions & 0 deletions _vandv/index.md
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Expand Up @@ -31,3 +31,8 @@ Results for the 30p30n airfoil, mesh independence study at low angle-of-attack,
Comparison of grid-converged results with experimental data. SA and SST turbulence models.
* [2D Flat Plate (T3A & T3A-) for Langtry and Menter transition model](/vandv/LM_transition/)
Comparison of grid-converged results with results of another solver and experimental data.

#### Incompressible Flow

* [2D Axisymmetric, Nonpremixed, Nonreacting, Variable Density, Turbulent Jet Flow](/vandv/SANDIA_jet/)
Comparison of grid-converged results with experimental data and other solvers for the Species Transport and Composition-Dependent model.