This slide is describing how to set up the OpenFOAM simulations including rotating geometries.
The SRF (Single Rotating Frame) is covered and MRF (Multiple Reference Frame).will be covered in it.
This document summarizes the results of running all tutorial cases in OpenFOAM-v1806. Over 300 cases were run and the results were compared to OpenFOAM-v1712. Some cases saw significant speed improvements while others slowed down, with unclear reasons in some cases. Mesh generation times also improved in many cases when using snappyHexMesh. New features were identified and animations were included to illustrate several cases. In conclusion, the number of tutorial cases increased from v1706 to v1812 and meshing and solver speeds varied significantly between versions.
Setting and Usage of OpenFOAM multiphase solver (S-CLSVOF)takuyayamamoto1800
?
The S-CLSVOF solver in OpenFOAM uses a coupled volume of fluid (VOF) and level set method to simulate multiphase flows. It uses a level set function to track the interface and reinitialize it, improving on the standard VOF method. The solver has been implemented in OpenFOAM versions 2.0.x and higher but boundary conditions for the level set function have not been fully developed. The document provides information on setting up and running a dam break tutorial case using the S-CLSVOF solver by modifying an existing interFoam case.
Spatial Interpolation Schemes in OpenFOAMFumiya Nozaki
?
The document discusses spatial interpolation schemes in OpenFOAM. It begins by explaining how spatial derivative terms in the finite volume method (FVM) are discretized by integrating over cell volumes and surfaces. It then describes how values at face centers are obtained by interpolating from cell center values using algebraic relationships and weighting factors. Common interpolation schemes in OpenFOAM include upwind, linearUpwind, linear, and limitedLinear. The specification of interpolation schemes on a term-by-term basis is demonstrated. Code examples show how schemes such as upwind, linearUpwind and midPoint calculate interpolated face values and weighting factors differently.
This slide is describing how to set up the OpenFOAM simulations including rotating geometries.
The SRF (Single Rotating Frame) is covered and MRF (Multiple Reference Frame).will be covered in it.
This document summarizes the results of running all tutorial cases in OpenFOAM-v1806. Over 300 cases were run and the results were compared to OpenFOAM-v1712. Some cases saw significant speed improvements while others slowed down, with unclear reasons in some cases. Mesh generation times also improved in many cases when using snappyHexMesh. New features were identified and animations were included to illustrate several cases. In conclusion, the number of tutorial cases increased from v1706 to v1812 and meshing and solver speeds varied significantly between versions.
Setting and Usage of OpenFOAM multiphase solver (S-CLSVOF)takuyayamamoto1800
?
The S-CLSVOF solver in OpenFOAM uses a coupled volume of fluid (VOF) and level set method to simulate multiphase flows. It uses a level set function to track the interface and reinitialize it, improving on the standard VOF method. The solver has been implemented in OpenFOAM versions 2.0.x and higher but boundary conditions for the level set function have not been fully developed. The document provides information on setting up and running a dam break tutorial case using the S-CLSVOF solver by modifying an existing interFoam case.
Spatial Interpolation Schemes in OpenFOAMFumiya Nozaki
?
The document discusses spatial interpolation schemes in OpenFOAM. It begins by explaining how spatial derivative terms in the finite volume method (FVM) are discretized by integrating over cell volumes and surfaces. It then describes how values at face centers are obtained by interpolating from cell center values using algebraic relationships and weighting factors. Common interpolation schemes in OpenFOAM include upwind, linearUpwind, linear, and limitedLinear. The specification of interpolation schemes on a term-by-term basis is demonstrated. Code examples show how schemes such as upwind, linearUpwind and midPoint calculate interpolated face values and weighting factors differently.
The document discusses dynamic mesh functionality in OpenFOAM. It describes how OpenFOAM handles mesh motions and topology changes using the Dynamic Mesh functionality. Settings for Dynamic Mesh are specified in the dynamicMeshDict file located in the constant directory. Solvers that can handle mesh changes have names containing "DyM", standing for Dynamic Mesh. Examples include pimpleDyMFoam and interDyMFoam. Various types of dynamic meshes are described, including those handling only motion and those enabling topological changes.
This document discusses two methods for obtaining contour surface positions from OpenFOAM simulations: 1) Using the OpenFOAM sample utility which extracts contour data along surfaces defined in a sampleDict file, and 2) Using Paraview to visualize and export contour data to CSV files. The sample utility creates surface data folders containing sampled contour positions, while Paraview allows contour visualization and automated output of positions over multiple time steps.
The document provides programming tips for OpenFOAM, including:
1) How to get a patch's ID from its name using findPatchID().
2) How to calculate the sum of a field over a specified patch using gSum().
3) How to access boundary values of a variable on a patch and the cells adjacent to the patch using boundaryField() and faceCells().
4) How to read cell zone definitions and access cell labels using cellZones() and findZoneID().
It also demonstrates using logical operators on boolLists, appending to DynamicLists, and removing duplicate values from a list.
Adjoint Shape Optimization using OpenFOAMFumiya Nozaki
?
The document describes an OpenFOAM shape optimization example where the goal is to modify a geometry to match a target parabolic velocity profile at the outlet by running the adjoint solver. Over 20 iterations, the geometry is modified based on sensitivity maps from the adjoint method, with inward displacements where sensitivity is positive and outward displacements where sensitivity is negative. This improves the match of the calculated outlet velocity distribution to the target profile by 64%.
CFD for Rotating Machinery using OpenFOAMFumiya Nozaki
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This document discusses setting up CFD simulations for rotating machinery using OpenFOAM. It describes the Single Rotating Frame (SRF) and Multiple Reference Frame (MRF) methods. The SRF method computes the flow in a single rotating frame of reference attached to the rotating machinery, allowing for steady-state or transient solutions without mesh motion. The MRF method computes the flow using both rotating and stationary frames, with the rotating zone solved in the rotating frame and stationary zones in the stationary frame. Tutorial cases for the SRF solvers SRFSimpleFoam and SRFPimpleFoam are presented to demonstrate implementing rotating boundary conditions and calculating additional force terms.
Enhancement of open-source computational-fluid-dynamics code OpenFOAM(R) for Detached-Eddy Simulation as presented on the OSCIC'10 in Munich 2010 by Dr. Ulf Bunge.
This document describes the design of a machine to directly measure contact line friction. It begins with background on contact angles and traditional methods for measuring contact angle hysteresis and pinning forces, such as the captive needle and tilting plate methods. It then outlines the design of the new measurement machine, which uses a linear motion stage to drag a droplet across a substrate while measuring the pinning force with a high precision force sensor. Key aspects of the design include the motion system, force sensor, vibration isolation, sample holder, enclosure box, and various adjustments for positioning and observation. The machine aims to directly measure pinning forces with improved accuracy compared to existing indirect methods.
Suse Studio: "How to create a live openSUSE image with OpenFOAM? and CFD tools"Baltasar Ortega
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Una descripci┏n de Suse Studio, adem│s de una magn┴fica explicaci┏n de su utilizaci┏n de la mano de Alberto Passalacqua.
"How to create a live
openSUSE image with OpenFOAM? and CFD tools"
OpenFOAM solver for Helmholtz equation, helmholtzFoam / helmholtzBubbleFoamtakuyayamamoto1800
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In this slide, we show the simulation example and the way to compile this solver.
In this solver, the Helmholtz equation can be solved by helmholtzFoam. Also, the Helmholtz equation with uniformly dispersed bubbles can be simulated by helmholtzBubbleFoam.
Calculation time and parallel efficiency are evaluated using OpenFOAM for EPYC server. The 3D lid driven cavity flow is simulated using different EPYC CPUs.
OpenFOAM benchmark for EPYC server -Influence of coarsestLevelCorr in GAMG so...takuyayamamoto1800
?
Parallel efficiency of GAMG solver in OpenFOAM is evaluated for EPYC server. Especially, in this study, the influence of coarsestLevelCorr on the calculation time is evaluated in lid driven cavity flow.
IoT Devices Compliant with JC-STAR Using Linux as a Container OSTomohiro Saneyoshi
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Security requirements for IoT devices are becoming more defined, as seen with the EU Cyber Resilience Act and Japan¨s JC-STAR.
It's common for IoT devices to run Linux as their operating system. However, adopting general-purpose Linux distributions like Ubuntu or Debian, or Yocto-based Linux, presents certain difficulties. This article outlines those difficulties.
It also, it highlights the security benefits of using a Linux-based container OS and explains how to adopt it with JC-STAR, using the "Armadillo Base OS" as an example.
Feb.25.2025@JAWS-UG IoT
14. References
?? D. A. Hoang et al., Comput. Fluids, 86, 28-36
(2013).
?? J. U. Brackbill et al., J. Comp. Phys., 100, 335-354
(1992).
?? A. Albadawi et al., Int. J. Multiphase Flow, 53,
11-28 (2013).