COMSOL Multiphysics^® 6.0 Release Highlights

Optimization Module Updates

For users of the Optimization Module, COMSOL Multiphysics^® version 6.0 brings a Transformation feature for setting up simple shape variations, revamped parameter estimation functionality for least-squares objective analyses, improved support for transient optimization, and more easily accessible optimization features. Read more about the features below.

Shape Optimization

For Shape Optimization, there is a new Transformation feature for you to quickly set up simple shape variations. This supports translation, scaling, and rotation, as well as custom coordinate systems. The simplicity of the shape variations guarantees that it is possible to construct a CAD representation of the optimization result. You can see this new feature in the existing Optimization of a Photonic Crystal for Signal Filtering and Optimization of a Photonic Crystal for Demultiplexing models, as well as in a new model called Optimization of a Waveguide Iris Bandpass Filter — Transformation Version.

A revolved 2D electromagnetic coil showing the magnetic flux density with black lines and a blue center.

The magnetic flux density of a revolved 2D electromagnetic coil.

View screenshot

Parameter Estimation

The setup of parameter estimation models has been simplified using a set of new tools and interfaces. A new Global Least-Squares Objective feature is available through the Component node. This feature has an improved user interface relative to the old feature (which is still available through the Optimization interface). In addition, a new Parameter Estimation study step has also been introduced, while the old Parameter Estimation study step has been renamed Curve Fitting. With this new study step, you can set up a least-squares objective directly in the study step, without needing to add a General Optimization interface, and it can also be used with least-squares objective features. Several tutorial models make use of the new parameter estimation functionality, including (but not limited to) the Impedance Tube Parameter Estimation with Data Generation, Mooney–Rivlin Curve Fit, Estimation of Corrosion Kinetics Parameters, and Modeling Impedance in the Lithium-Ion Battery models.

The Impedance Tube Parameter Estimation with Data Generation model demonstrates how to use the new Parameter Estimation study step for estimating poroacoustic parameters based on impedance tube measurements.

Transient Optimization

Running transient sensitivity analyses is more robust with improvements to the solver settings. Additional robustness can be achieved by using fixed time steps and/or a new manual solver setting that allows solving the transient adjoint problem using the same time steps as the forward problem. Separately, a new Control Function feature allows for control variables that vary in time. The argument can be time, as in the Optimal Control for Heating of a Cylinder model, or chosen arbitrarily as shown in the Shape Optimization of a Rectangular Loudspeaker Horn in 3D model, where the feature is used for shape optimization. The Optimization of a Tesla Microvalve with Transient Flow model also makes use of the improvements for transient optimization.

The COMSOL Multiphysics UI showing the Model Builder with the Control Function node highlighted, the corresponding Settings window, a 1D plot in the Graphics window, and the Objective Probe Table.

The Optimal Control for Heating of a Cylinder model demonstrates how to use the Control Function feature to achieve a certain temperature as fast as possible. In this case, the feature is used with time as the argument.

Relocated Optimization Features

In addition to the new and updated functionality, how to access the user interfaces of the Optimization Module has changed. The optimization features that were located under the Definitions node have been elevated to exist on the same level as the physics interfaces. This change makes the optimization features easier to access and also more visible in the model tree.

View screenshot

New and Updated Tutorial Models

COMSOL Multiphysics^® version 6.0 brings several new and updated tutorial models to the Optimization Module.

Loudspeaker Spider Optimization

An optimized loudspeaker spider model showing the stress at the center in the Rainbow color table.

The stress in the shape-optimized spider is plotted in a revolved representation. The optimization starts from a flat design and introduces wrinkles to minimize the nonlinearity of the spider.

Application Library Title:
loudspeaker_spider_optimization
Download from the Application Gallery

Shape Optimization of Coils

The Transformation feature is used to optimize the radial position of some rectangles used to model the cross sections of an electromagnetic coil. The objective is to achieve a uniform field at the center of the structure and at the same time minimize the field at the axis ends.

Application Library Title:
coil_shape_optimization
Download from the Application Gallery

Optimization of a Waveguide Iris Bandpass Filter — Transformation Version

An RF filter model showing two cropped rectangles with two lime-green arrows representing size and position.

The size and positions of some rectangles are optimized for an RF filter. The objective is to move and scale some contractions to get good out-of-band rejection as well as good bandpass response.

Application Library Title:
waveguide_iris_filter_optimization_transformation
Download from the Application Gallery

Topology Optimization of a Drone

A drone model with removed material, showing the simulated displacement under load in the Rainbow color table.

The drone model demonstrates 3D topology optimization with iterative solvers. The objective is to retain as much stiffness as possible for two load cases, while removing 87.5% of the material.

Application Library Title:
drone_topology_optimization
Download from the Application Gallery

Petzval Lens Optimization

A spot diagram of a Petzval lens model with green, blue, and red dots representing three wavelengths.

This tutorial shows how to set up a multielement objective lens. The figure shows the spot diagram for three wavelengths with a field angle of 6°, but 0° and 9° are also considered in the optimization.

Application Library Title:
petzval_lens_optimization
Download from the Application Gallery

Topology Optimization of a District Heating Network

A rectangular pipe network in the Rainbow color table with two heat producers.

The optimal pipe network is plotted for a rectangular consumer layout with two heat producers. The optimization minimizes the cost of establishing and running the network, while ensuring that none of the household inhabitants freeze.

Application Library Title:
district_heating_optimization
Download from the Application Gallery

Shape Optimization of a Plate Heat Exchanger

A plate heat exchanger model with two inlets and two outlets shown in the Rainbow color table.

This model demonstrates how to use the built-in shape optimization functionality for a plate heat exchanger. The shape of the separating plate is optimized to increase the heat transfer rate for a pressure-driven flow.

Application Library Title:
plate_heater_exchanger_optimization
Download from the Application Gallery

Optimization of a Tesla Microvalve with Transient Flow

A Tesla valve model showing particle tracing for five oscillations in the Rainbow color table representing time.

The model demonstrates topology optimization for transient flow in a Tesla valve. The flow has a sinusoidal oscillation and the design is verified with a body-fitted mesh. The figure shows particle tracing for five oscillations, where the color of each line represents time.

Application Library Title:
tesla_microvalve_transient_optimization
Download from the Application Gallery

Topology Optimization of a Heat Exchanger with Laminar Flow

A 2D plot of a heat exchanger model showing the total velocity in the Rainbow color table and black streamlines representing the flow.

This model demonstrates topology optimization of a heat exchanger with laminar flow. The objective is to maximize the heat transfer rate for a pressure-driven flow, so the optimization finds a balance between hydraulic resistance and thermal coupling between the two fluids.

Application Library Title:
heat_exchanger_2d_topology_optimization
Download from the Application Gallery

Optimal Control for Heating of a Cylinder

A 1D plot showing the outer temperature (blue line), the inner temperature (green line), and power (red line) of a heating problem.

This model demonstrates optimal control for a heating problem. The idea is to reach a certain temperature as fast as possible by changing the input power. The graph shows a Bernstein polynomial, but it is possible to regularize the control using a Helmholtz filter instead and get similar results.

Application Library Title:
optimal_heating_control
Download from the Application Gallery

Shape Optimization of a Rectangular Loudspeaker Horn in 3D

Three loudspeaker models with the Wave Light color table and black streamline plots.

This model demonstrates the use of the Control Function and Transformation features for shape optimization with the new exterior field optimization function. The horn is first optimized for on-axis performance and then the speaker is allowed to rotate, so that good off-axis performance can be improved.

Application Library Title:
rectangular_horn_shape_optimization
Download from the Application Gallery

Shape Optimization of a Water Heater

A rectangular water heater model with gray and black lines representing the old and new geometry and two green arrows showing the deformation.

This model demonstrates the Transformation features for shape optimization of a microwave water heater. The objective is to maximize the heating of the water in a pipe by changing the size and position of the pipe as well as the length and position of some conducting walls.

Application Library Title:
water_heater_optimization
Download from the Application Gallery

COMSOL Multiphysics® 6.0 Release Highlights