COMSOL Multiphysics® is a general-purpose software platform, based on advanced numerical methods, for modeling and simulating physics-based problems. With COMSOL Multiphysics, you will be able to account for coupled or multiphysics phenomena. With more than 30 add-on products to choose from, you can further expand the simulation platform with dedicated physics interfaces and tools for electrical, mechanical, fluid flow, and chemical applications. Additional interfacing products connect your COMSOL Multiphysics simulations with technical computing, CAD, and ECAD software.
COMSOL Desktop® is a powerful integrated environment designed for cross-disciplinary product development with a unified workflow, regardless of the application area. The add-on modules blend in seamlessly with COMSOL Multiphysics, and the way you operate the software remains the same no matter which add-on products are engaged. The model tree in the Model Builder gives you a full overview of the model and access to all functionality – geometry, mesh, physics settings, boundary conditions, studies, solvers, postprocessing, and visualizations. With COMSOL Multiphysics you can easily extend conventional models for one type of physics into multiphysics models that solve coupled physics phenomena – simultaneously. What’s more, accessing this power does not require in-depth knowledge of mathematics or numerical analysis.
A silicon wafer is heated up by a laser that moves radially in and out over time. In addition, the wafer itself is rotated on its stage. The incident heat flux from the laser is modeled as a spatially distributed heat source on the surface. The transient thermal response of the wafer is shown. The peak, average, and minimum temperature during the heating process is computed, as well as the temperature variations across the wafer.
This example studies a laminar static micromixer with two parallel sets of split-reshape-recombine mixing elements. The mixer works through lamination of the streams without any moving parts and the mixing is obtained through diffusion.
The purpose of this model is to demonstrate how to access the cluster computing functionality in COMSOL from COMSOL Desktop and use it to submit a batch job to a cluster through a job scheduler.
A model of a thermal microactuator requires the coupled simulation of electric current conduction with heat generation, heat conduction, and structural stresses and strains due to thermal expansion.
The purpose of this model is to demonstrate how to access the cluster computing functionality in COMSOL from COMSOL Desktop and use it to submit a batch job to a cluster through a job scheduler. The model takes advantage of the distributed parameter functionality in COMSOL. The model also demonstrates how you can measure the speedup of COMSOL on your cluster.
The following model examines unsteady, incompressible flow past a long cylinder placed in a channel at right angle to the oncoming fluid. The cylinder is offset somewhat from the center of the flow to make the steady-state symmetrical flow unstable.
The simulation time necessary for a periodic flow pattern to appear is difficult to predict. A key predictor is the Reynolds number, which is based on cylinder diameter. For low values—below 100—the flow is steady.
In this simulation the Reynolds number equals 100, which gives a developed Karman vortex street; but the flow is still not fully turbulent.
The development of mixers does often not only have to account for effectiveness, but also other factors must be involved, such as cost and complexity for manufacturing. The three models study a laminar static micro mixer with two parallel sets of split-reshape-recombine mixing elements.
The mixer works through lamination of the streams without any moving parts and the mixing is obtained through diffusion, which makes it cheap and easy to manufacture.
When a tuning fork is struck, it vibrates in a complex motion pattern that can be described mathematically as the superposition of resonant modes, also known as eigenmodes. Each mode is associated with a particular eigenfrequency. The tuning fork produces its characteristic sound from the specific timbre that is created by the combination of all of the eigenfrequencies.
The Tuning Fork app computes the fundamental resonant frequency of a tuning fork where you can change the prong length. Alternatively, you can provide a user-defined target frequency and the application will find the corresponding prong length using an algorithm based on a secant method.
This tutorial demonstrates how to import and create a geometry from a surface mesh saved in the STL format. The instructions detail how to remove isolated faces from the imported STL mesh, how to use the geometry import parameters, and how to create volumes for simulation both on the inside and the outside of the imported geometric object.
The STL geometry in this example is provided courtesy of Mark Yeoman, Continuum Blue, UK (https://www.comsol.com/certified-consultants/continuum).
Chemical engineering students can model a nonideal tubular reactor, including radial and axial variations in temperature and composition, and investigate the impact of different operating conditions with this easy-to-use app. The process described by the Tubular Reactor with Nonisothermal Cooling Jacket app is the exothermic reaction of propylene oxide with water to form propylene glycol, assuming first-order reaction kinetics.
The reactor also contains a cooling jacket, and the application consists of an energy and material balance. The student can change the activation energy of the reaction, the thermal conductivity, and the heat of reaction to investigate a variety of scenarios.
The resulting solution gives the axial and radial reaction conversion as well as the temperature profile.
This example uses the Transport of Diluted Species and Heat Transfer in Fluids interfaces as available in the COMSOL Multiphysics base package to study an elementary, exothermic, irreversible reaction in a tubular reactor (liquid phase, laminar flow regime). To keep its temperature down, the reactor also uses a cooling jacket with a nonisothermal coolant temperature. The coolant is modeled with a Coefficient Form Boundary PDE. The steady-state behavior of the reactor is investigated.
The reaction taking place in the tubular reactor is propylene oxide (A) reacting irreversibly with water (B) to form propylene glycol (C):
A + B -> C
Since water is the solvent and present in abundance, the reaction kinetics are described as first order with respect to propylene oxide:
R = k*C_A
This application solves the example by S. Fogler in Elements of Chemical Reaction Engineering 4th ed., (Prentice Hall, 2005), p. 557 (Example 8-12 Radial Effects in Tubular Reactor)
As an example of how to build an app using the Application Builder, this application simulates the transient response of a beam, or bridge, that is placed on several equidistant supports and is subjected to a traveling load.
The purpose of the Beam Subjected to Traveling Load app is to analyze the structural response of a bridge when vehicles pass over it. Many of the bridge’s parameters can be varied, such as its material properties and many of its geometric parameters.
One observation from the analysis is that certain vehicle speeds cause resonance in the bridge and it undergoes high amplitude oscillation.