The stationary droplet by Lionel Gamet - Revision history

Jozsef Nagy at 07:36, 26 January 2024

2024-01-26T07:36:52Z

Jozsef Nagy at 12:06, 30 August 2022

2022-08-30T12:06:17Z

Jozsef Nagy: /* The stationary droplet */

2021-12-03T06:06:36Z

The stationary droplet

Jozsef Nagy: /* Running the case */

2021-12-03T06:05:47Z

Running the case

Jozsef Nagy at 06:02, 3 December 2021

2021-12-03T06:02:33Z

Jozsef Nagy at 07:50, 17 September 2020

2020-09-17T07:50:25Z

Jozsef Nagy at 05:48, 17 September 2020

2020-09-17T05:48:08Z

Jozsef Nagy at 05:44, 17 September 2020

2020-09-17T05:44:15Z

Jozsef Nagy at 05:42, 17 September 2020

2020-09-17T05:42:59Z

Jozsef Nagy at 05:37, 17 September 2020

2020-09-17T05:37:52Z

@@ Line 4: / Line 4: @@
 * '''affiliation''': IFP Energies nouvelles, France
 * '''contact''': <mail address='lionel.gamet@ifpen.fr' description='author'>click here for email address</mail>
-* '''OpenFOAM version''': v2206
+* '''OpenFOAM version''': v2312
 * '''Published under''': CC BY-NC-SA license ([https://creativecommons.org/licenses creative commons licenses])

@@ Line 4: / Line 4: @@
 * '''affiliation''': IFP Energies nouvelles, France
 * '''contact''': <mail address='lionel.gamet@ifpen.fr' description='author'>click here for email address</mail>
-* '''OpenFOAM version''': v2106
+* '''OpenFOAM version''': v2206
 * '''Published under''': CC BY-NC-SA license ([https://creativecommons.org/licenses creative commons licenses])

@@ Line 17: / Line 17: @@
 * [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/3D.tar 3D case].
 * [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/3D_uns.tar Unstructured 3D case].
 Reference OpenFOAM results of the stationary droplet can be found [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/StationaryDroplet_Results.tar.gz here].

@@ Line 66: / Line 66: @@
 ==Running the case==
-'''<code>Allrun_sensitivity</code> should be run first.''' This script is at a level above <code>Allrun</code>. It is used to prepare a grid size and Laplace sensitivity study (optionally density: By default, density is set to 1. Optionally, density can be set to 1, 10, 100, 1000 by changing line 21 in the script <code>Allrun_sensitivity</code>), for solvers <code>interFoam</code>, <code>interIsoFoam</code>, and also the enhanced version of isoAdvector by H. Scheufler, now partially integrated in the v2006 with the plicRDF reconstruction scheme. <code>Allrun_sensitivity</code> will create subdirectories ready to run, with a number of cells 25, 32, 42, 50, 64, 75, 100, 128 and 150.
+'''<code>Allrun_sensitivity</code> should be run first.''' This script is at a level above <code>Allrun</code>. It is used to prepare a grid size and Laplace sensitivity study (optionally density: By default, density is set to 1. Optionally, density can be set to 1, 10, 100, 1000 by changing line 21 in the script <code>Allrun_sensitivity</code>), for solvers <code>interFoam</code>, <code>interIsoFoam</code>, and also the enhanced version of isoAdvector by H. Scheufler, now partially integrated in the v2106 with the plicRDF reconstruction scheme, but also publicly available from the [https://github.com/DLR-RY/TwoPhaseFlow TwoPhaseFlow] git repository. <code>Allrun_sensitivity</code> will create subdirectories ready to run, with a number of cells 25, 32, 42, 50, 64, 75, 100, 128 and 150.
 The fluid viscosity is computed in <code>Allrun_sensitivity</code> from the Laplace number through the relation:

@@ Line 4: / Line 4: @@
 * '''affiliation''': IFP Energies nouvelles, France
 * '''contact''': <mail address='lionel.gamet@ifpen.fr' description='author'>click here for email address</mail>
-* '''OpenFOAM version''': v2006
+* '''OpenFOAM version''': v2106
 * '''Published under''': CC BY-NC-SA license ([https://creativecommons.org/licenses creative commons licenses])

@@ Line 52: / Line 52: @@
 [[File:Gamet_Eq3.png|280px|center|]]
-with Co the Courant number as entered in <code>controlDict</code> and &Delta;x=1/N, with N the number of grid cells along a coordinate direction. Writing interval for time directories is set every 10 \,t_&sigma;. The constant time step is adjusted so that a writing interval corresponds to a whole number of time steps, multiple of 1000.
+with Co the Courant number as entered in <code>controlDict</code> and &Delta;x=1/N, with N the number of grid cells along a coordinate direction. Writing interval for time directories is set every 10 t_&sigma;. The constant time step is adjusted so that a writing interval corresponds to a whole number of time steps, multiple of 1000.
-Post-processing quantities of interest are described in details in . The main interest of this test case is to provide us with a measure of spurious currents. Those are obtained by recording minimum and maximum of velocity versus time overall the domain, thanks to a <code>fieldMinMax</code> functionObject. Of particular interest is the maximum of magnitude of velocity over the domain, which can be made dimensionless in terms of a maximum capillary number as:
+Post-processing quantities of interest are described in details in [1]. The main interest of this test case is to provide us with a measure of spurious currents. Those are obtained by recording minimum and maximum of velocity versus time overall the domain, thanks to a <code>fieldMinMax</code> functionObject. Of particular interest is the maximum of magnitude of velocity over the domain, which can be made dimensionless in terms of a maximum capillary number as:
 [[File:Gamet_Eq4.png|280px|center|]]

@@ Line 74: / Line 74: @@
 La numbers are taken as 1.2, 12, 120, 1200 and 12000.
-[[File:StDrop3D_La_vary_CaMax_32_struct.png|560px|center|Static droplet in 3D: Maximum capillary number over the computational domain for a hexahedral grid of size 323 versus nondimensional time, for different Laplace numbers. Solvers interFoam (MULES), interIsoFoam (iso-Alpha) and the enhanced version of isoAdvector by H. Scheufler [7] (plicRDF-5).]]
+You need to enter each generated subdirectory and type <code>Allrun</code> to start the corresponding computation. The grid is first constructed by running <code>blockMesh</code>. Then the <code>setAlphaField</code> utility is run to initialize the droplet as a cylinder. Finally, the application is run. Post-processing quantities of interest (droplet characteristics and spurious currents intensity) are extracted from the solver outputs through <code>grep</code> commands and simple computations.
 ==References==

← Older revision		Revision as of 05:44, 17 September 2020
Line 74:		Line 74:
	La numbers are taken as 1.2, 12, 120, 1200 and 12000.		La numbers are taken as 1.2, 12, 120, 1200 and 12000.

−	[[File:~~StDrop3D_La=vary_CaMax_32_struct~~.png\|560px\|center\|Static droplet in 3D: Maximum capillary number over the computational domain for a hexahedral grid of size 323 versus nondimensional time, for different Laplace numbers. Solvers interFoam (MULES), interIsoFoam (iso-Alpha) and the enhanced version of isoAdvector by H. Scheufler [7] (plicRDF-5).]]	+	[[File:StDrop3D_La_vary_CaMax_32_struct.png\|560px\|center\|Static droplet in 3D: Maximum capillary number over the computational domain for a hexahedral grid of size 323 versus nondimensional time, for different Laplace numbers. Solvers interFoam (MULES), interIsoFoam (iso-Alpha) and the enhanced version of isoAdvector by H. Scheufler [7] (plicRDF-5).]]

@@ Line 14: / Line 14: @@
 * [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/2D.tar 2D case].
-* [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/2D_uns.tar Unsteady 2D case].
+* [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/2D_uns.tar Unstructured 2D case].
 * [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/3D.tar 3D case].
-* [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/3D_uns.tar Unsteady 3D case].
+* [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/3D_uns.tar Unstructured 3D case].
 Reference OpenFOAM results of the stationary droplet can be found [https://github.com/jnmlujnmlu/OpenFOAMTeaching/blob/master/LionelGamet/StationaryDroplet_Results.tar.gz here].
@@ Line 65: / Line 65: @@
 ==Running the case==
 [[File:Gamet_Eq5.png|280px|center|]]

← Older revision		Revision as of 05:37, 17 September 2020
Line 60:		Line 60:
	The maximum capillary number is computed in the <code>Allrun</code> script, from the <code>fieldMinMax</code> output.		The maximum capillary number is computed in the <code>Allrun</code> script, from the <code>fieldMinMax</code> output.

		+	Other integral quantities of interest are the droplet volume and area, the droplet global velocity, the droplet circularity. All these quantities are computed through a coded functionObject inlined in the <code>controlDict</code> file, similar to the Hysing benchmark case. Please note that the droplet centroid of mass corresponds to the simulated portion (1/4th in 2D or 1/8th in 3D). The droplet centroid is thus not the origin. These integral results appear in the log file of the solver. We use a <code>sampledIsoSurfaceCell</code> object, defined as the isosurface α = 0.5, to compute the droplet area. We use volume integrals of the liquid fraction overall the computational domain to compute the droplet volume, centroid and velocity. A droplet equivalent diameter named D_A is computed from the droplet volume. A droplet equivalent diameter named D_B is computed from the droplet area. The circularity is defined in 2D as the ratio D_A/D_B. In 3D, we talk about sphericity defined as the ratio D_A^2/D_B^2. This number takes the value 1 at t=0 as the droplet is initialized as a perfect cylinder (or sphere in 3D).

		+	Finally, the droplet shape and pressure profiles are output at <code>writeTime</code> frequency through <code>surfaces</code> and <code>sets</code> sampling functionObjects. The droplet shape is based upon the isosurface α=0.5. Both interpolated and constant iso droplet shapes are output.

	==Running the case==		==Running the case==