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Optical Scattering Off of a Gold Nanosphere
This model demonstrates the simulation of the scattering of a plane wave of light by a gold nanosphere. The scattering is computed for the optical frequency range over which gold can be modeled as a material with negative complex-valued permittivity. The far-field pattern and losses are computed.
Magnetic Field of a Helmholtz Coil
A Helmholtz coil is a parallel pair of identical circular coils spaced one radius apart and wound so that the current flows through both coils in the same direction. This winding results in a uniform magnetic field between the coils with the primary component parallel to the axes of the two coils. Applications of Helmholtz coils range from canceling the earth’s magnetic field to generating ...
Capillary Filling - Phase Field Method
This example studies a narrow vertical cylinder placed on top of a reservoir filled with water. Because of wall adhesion and surface tension at the air/water interface, water rises through the channel. Surface tension and wall adhesive forces are often used to transport fluid through microchannels in MEMS devices or to measure, transport and position small amounts of fluid using micropipettes. ...
Buoyancy Flow of Free Fluids
This model couples the Navier Stokes equations and the heat transfer equations to examine density driven flow of free fluids. Here the fluid is in a square cavity with a heated wall. The buoyancy force is a Boussinesq term added to the Navier-Stokes equations. The equation is nondimensionalized, so the material coefficients are set up using Rayleigh and Prandtl numbers. The parametric solver ...
Steady-State 2D Heat Transfer with Conduction
This example shows a 2D steady-state thermal analysis including convection to a prescribed external (ambient) temperature. It is given as a benchmarking example. The benchmark result for the target location is a temperature of 18.25 C. The COMSOL Multiphysics model, using a default mesh with 556 elements, gives a temperature of 18.28 C. Successive uniform refinements show a temperature of 18.26 ...
Voltage Induced in a Coil by a Moving Magnet
A magnet moving axially through the center of a coil will induce a voltage across the coil terminals. One practical application of this is in shaker flashlights, where the flashlight is vigorously shaken back and forth, causing a magnet to move through a multi-turn coil, which provides charge to the battery. In this model, the motion of a magnet through a coil is modeled, and the induced ...
Rock Fracture Flow
A potential flow model of fluid flow in a rock fracture uses the so-called Reynolds equation. It shows how to use experimental data interpolated to a function used in the equation.
Axisymmetric Transient Heat Transfer
This is a benchmark model for an axisymmetric transient thermal analysis. The temperature on the boundaries changes from 0 degrees C to 1000 degrees C at the start of the simulation. The temperature at 190 s from the anlysis is compared with a NAFEMS benchmark solution.
Frequency Selective Surface, Periodic Complementary Split Ring Resonator
Frequency selective surfaces (FSS) are periodic structures with a bandpass or a bandstop frequency response. This model shows that only signals around the center frequency can pass through the periodic complementary split ring resonator layer.
Loudspeaker Driver
This example shows you how to model a loudspeaker of the dynamic cone driver type, common for low and medium frequencies. The model analysis includes the total electric impedance and the on-axis sound pressure level at a nominal driving voltage, as functions of the frequency. The spatial characteristics of the speaker are depicted in a directivity plot. The tutorial model is set up using a ...
