Post on 12-Jan-2016
Multiphysics Modelingin
FEMLAB 2.2Fall 2001
COMSOL
Contents
• Introduction• Modeling in FEMLAB
– A first simple model of direct current conduction
• Influence of wave guide geometry on wave propagation– 3D Electromagnetics
• Reaction distribution in a monolithic reactor– Chemical engineering and transport phenomena
• Study of the stresses in a guyed mast– Preview of the upcoming structural mechanics module
• Support and courses
Why modeling ?
• Education– Accelerates understanding
• Saves time and money– Rapid prototyping
• Safety– Spares equipment
• Fun?
Our company
• Founded in 1986 by two Ph.D. Students at the Royal Institute of Technology
• Developed several products within the Matlab family
• 95 employees in offices in Sweden, Finland, Norway, Denmark, USA, Germany, UK and France
• We want to provide user-friendly and powerful software for modeling in education, research, design, and development
Our first FEMLAB model
• Shows the main steps of the modeling process in FEMLAB
• Highlights– Single physics– 2D and 3D drawing tools– Several subdomains with different
properties– Post processing including boundary
integration– M-file features
Problem definition
V = 1
V = 0
V = 0
V
Outflow 2
Outflow 1
How is the current distributed between outflows 1 and 2 ?
Results
Integrate current density
Integrate current density
Summary of the modeling process
• Draw Mode• Boundary Mode• Subdomain Mode• Mesh Mode• Post Mode
Study of waveguide geometry in 3D
• How does the geometry influence the reflection of the wave?
• How is the mode of the traveling wave changed in the waveguide ?
• Exemplifies the use of FEMLAB in prototyping
• Shows the new 3D Electromagnetics Module
Problem definition
Incomingwave
Transmittedwave
x(xE) - k2E = 0
nx(xE) + ikEt = 2ikEinc
Is there a change in mode ? What is the dependency between the frequency andthe reflection coefficient?
Results
InOut
propagating wave standing wave
A frequency of 8.1 GHz gives minimal reflection, 7 %
The incoming TE11-mode is transformed to a TE10-wave
Results: S-parameters
Frequency (Hz)
minimal reflection
|S21|2
Results: S-parameters
• The S-parameter S21 (for open-ends) is:
• This can be computed as boundary integrals in the FEMLAB GUI
input throughflow Powerouput throughflow Power
21S
Reaction distribution in a monolithic reactor
• To which extent is the catalyst utilized ?
• How will the catalyst degrade due to temperature effects ?
• Exemplifies the use of FEMLAB in chemical reaction engineering design
• Shows the new version of the chemical engineering module
Problem definition
(-Dc + cv) = 0
(-Dc) + kc = 0
Inlet
Outlet
Porouscatlyst
Free fluid
Results
• Substantial depletion within the catalyst at a given z-position
• Utilization of the catalyst is not optimal
• Depletion along the z-axis gives a fairly good reactor performance
Socket for a guyed mast
• Minimize transport and material costs• Minimize weight and maximize
mechanical strength• Study the distribution of stresses in a
suggested design• Decide if we should pursue the work
based upon the suggested design, which implies a displacement below 0.1 mm at the thinnest part
Socket in a guyed mast
Guyed mast for telecom
Problem definition
z
no displacementin z-direction
Psymmetry
symmetry
¼ is modeled due to symmetry
2
ut2c u = K
Navier’s equations
ResultsVon Misses stresses and displacement
Maximum stress and displacement
max stress
Support & courses
• Experienced engineering staff
• Searchable FAQ database
• Extensive technical:support@femlab.com
• Download minicourse, apply for on-site minicourse or attend to our courses
• Developer Zone
Next step
• Download white papers, articles product sheets etc.
• Try FEMLAB yourself at hands-on seminars or trials
• Apply for on-site seminars and hands-on seminars
• Run tutorials and models at www.femlab.com