Comsol Multiphysics - DidatticaWEB
Transcript of Comsol Multiphysics - DidatticaWEB
Comsol Multiphysics
Anno Accademico 2018/2019
Cristina Falcinelli, PhD
COMSOL Multiphysics• Almost all physical phenomena can be described by partial differential equations (PDEs)
• In general, almost all cases fall into the class that has “non-trivial” or “non-analytical” solutions
• Then numerical methods as Finite Element (FE) method are necessary to solve the problem
Powerful interactive environment for modeling and solving all kinds of scientific and engineering problems based on partial differential equations through FE analysis
COMSOL
COMSOL Multiphysics
FE method uses discretization (nodes and elements) to model the domain: the problem system is subdivided into small components called elements and the elements are comprised of nodes MESHING
Finite ElementsNodal Points
COMSOL Multiphysics
Finite Elements
Nodal Points
1D ElementsLine
2D ElementsTriangular, Quadrilateral
Plates, Shells
3D ElementsTetrahedral, Rectangular
Prism (Brick)
COMSOL Multiphysics
Finite Elements
Nodal Points
• Assign nodes to each element and then choose the interpolation function to represent the variation of the variable over the element.
• Obtain a set of algebraic equations to solve for unknown (first) nodal quantity (displacement).
• Secondary quantities (stresses and strains) are expressed in terms of nodal values of primary quantity
Features:
COMSOL Multiphysics
Finite Elements
Nodal Points
Different fields of application:
The COMSOL Multiphysics approach
Fluid Flow
Chemical Reactions
Acoustics
Electromagnetic Fields
Heat Transfer
Structural Mechanics
User Defined Equations
The COMSOL Multiphysics
Tips and useful informations:
• English
• LiveLink for Matlab
• Unit of measure
• Help
The COMSOL Multiphysics
Model Wizard(Creatore Modelli)
or Blank Model(Modello Vuoto)
The COMSOL Multiphysics
Model Wizard or Blank Model
The COMSOL Multiphysics
Select Space Dimension
The COMSOL Multiphysics
Select Physics e.g. StructuralMechanics
The COMSOL Multiphysics
Select Physics e.g. StructuralMechanics Solid Mechanics ADD
The COMSOL Multiphysics
Study
The COMSOL Multiphysics
e.g. Stationary
Done
The COMSOL Multiphysics
The COMSOL Multiphysics
Model Wizard or Blank Model
The COMSOL Multiphysics
The COMSOL Multiphysics
Add Component1D, 2D, 3D
AddPhysics
AddStudy
The COMSOL Multiphysics
Recovery file
The COMSOL Multiphysics
Documentation
The COMSOL Multiphysics
Documentation
The COMSOL Multiphysics
Documentation
Searchexpression
The COMSOL Multiphysics
ApplicationLibraries
The COMSOL Multiphysics
ApplicationLibraries
Open ApplicationOpen PDF Document
The COMSOL Multiphysics
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
The COMSOL Multiphysics
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
Definitions
Parameters
The COMSOL Multiphysics
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
Geometry
The geometry can becreated or imported
The COMSOL MultiphysicsMaterial
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
The COMSOL MultiphysicsPhysics
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
The COMSOL MultiphysicsMesh
Physics-controlledmesh
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
Extremely fineExtra fineFinerFineNormal….
The COMSOL MultiphysicsMesh
User-controlledmesh
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
SizeFree Tetrahedral
The COMSOL MultiphysicsSolve
Compute
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
The COMSOL MultiphysicsResults
Model Builder: The model tree gives an overview of the model and all
the functionality and operations needed for building and solving a modelas well as processing the results
Post-processing
The COMSOL Multiphysics
Settings Window: click any node in the model tree to see itsassociated settings window displayed next to the Model Builder
The COMSOL Multiphysics
Settings Window: click any node in the model tree to see itsassociated settings window displayed next to the Model Builder
WidthDepthHeight
The COMSOL Multiphysics
Graphics Window: The graphics window presents interactive graphics
for the geometry, mesh and results. Operations include rotating, panning, zooming and selecting
The COMSOL Multiphysics
How to set up and run a simulation with Comsol Multiphysics?
Simulation workflow:
• Set up model environment
• Create geometrical objects
• Specify material properties
• Define physics boundary conditions
• Create the mesh
• Run the simulation
• Postprocess the results
The COMSOL Multiphysics
Let’s start with an example!
The COMSOL Multiphysics
1) Cubetto di materiale elastico lineare isotropo a cui applichiamo un campo di deformazioni (homogeneous strain BC) misuriamo le
tensioni generate. Per definire un materiale elastico lineare isotropo servono solo due costanti materiali E e ν (E=12 GPa, ν=0.32)
In elasticità lineare:
Matrice di rigidezza (6X6) Matrice di cedevolezza (6X6)
Se il materiale non possiede simmetrie costitutive (materiale anisotropo), le due matrici hanno 21 costanti elastiche indipendenti nel caso di materiale isotropo le costanti elastiche indipendenti si riducono a 2
The COMSOL Multiphysics
1) Cubetto di materiale elastico lineare ortotropo a cui applichiamo un campo di deformazioni (homogeneous strain BC) misuriamo le
tensioni generate. Materiale ortotropo: esistono 3 piani di simmetria ortogonali tra loro.
In elasticità lineare:
Matrice di rigidezza (6X6) Matrice di cedevolezza (6X6)
Se il materiale non possiede simmetrie costitutive (materiale anisotropo), le due matrici hanno 21 costanti elastiche indipendenti nel caso di materiale ortotropo le costanti elastiche indipendenti si riducono a 9