The Application Gallery features COMSOL Multiphysics® tutorial and demo app files pertinent to the electrical, structural, acoustics, fluid, heat, and chemical disciplines. You can use these examples as a starting point for your own simulation work by downloading the tutorial model or demo app file and its accompanying instructions.
Search for tutorials and apps relevant to your area of expertise via the Quick Search feature. Note that many of the examples featured here can also be accessed via the Application Libraries that are built into the COMSOL Multiphysics® software and available from the File menu.
A dielectric resonator placed near a radiating element can be used to increase directivity and gain. Here, a block of quartz dielectric, with additional passive metallic antenna elements, is placed above a slot antenna. The fields in and around the antenna are solved for. The far field ... Read More
A waveguide filter is designed using shape optimization. The irises of the initial geometry are optimized to ensure good bandpass response and out-of-band rejection, while maintaining the double mirror symmetry. Read More
A conductive diaphragm, an iris, placed transverse to a waveguide aperture causes a discontinuity and generates shunt reactance. Bandpass frequency response can be achieved from cascaded cavity resonators combined with these reactive elements which can be created by inserting a series of ... Read More
In signal integrity (SI) applications, time-domain reflectometry (TDR) is a useful technique for analyzing the discontinuity in a signal path by observing the reflected signal strength. The reflected signal distorts the input pulse mainly by impedance mismatch if there is no external ... Read More
In mode analysis it is usually the primary goal to find a propagation constant. This quantity is often, but not always, real valued; if the analysis involves some lossy part, such as a nonzero conductivity or an open boundary, the eigenvalue is complex. In such situations, the real and ... Read More
A large reflector can be modeled easily with the 2D axisymmetric formulation. In this model, the radius of the reflector is greater than 20 wavelengths and the reflector is illuminated by an axial feed circular horn antenna. The simulated far-field shows a high-gain sharp beam pattern Read More
A wideband antenna study, such as an S-parameter or far-field pattern analysis, can be obtained by performing a transient response analysis and a time-to-frequency fast Fourier transform (FFT). This model runs a time dependent study first and then transforms the dependent variable, the ... Read More
This model uses the Semiconductor and RF modules to describe a photoconductive antenna (PCA). A laser pulse is applied on the surface of undoped LT-GaAs to generate electron-hole-pairs, which move under the influence of an external E-field creating a transient electric current pulse. ... Read More
This Application Gallery entry demonstrates how Far-Field radiation can be calculated when a substrate is present. Two approaches are demonstrated. A simplified form that works for two homogeneous domains, and a general approach that can handle multiple, inhomogeneous layers. This ... Read More
A cascaded cavity filter provides much better bandpass filter performance compared to a single cavity. Out-of-band rejection improves dramatically using a cascaded design. This model uses three rectangular cavity filters coupled via slots. The calculated S-parameters show excellent out ... Read More