# Application Gallery

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. To download the MPH-files, log in or create a COMSOL Access account that is associated with a valid COMSOL license. 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.

### 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.

### An Integro-Partial Differential Equation

The heat distribution in a hollow pipe, whose ends are held at two different temperatures, is studied. The outside surface is assumed to be thermally isolated and the inner surfaces have radiation boundary conditions. The role of convection in the heat transfer is taken to be negligible. The temperature is assumed to be constant along the thickness of the pipe and rotational symmetry is also ...

### Tuning Fork

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 ...

### Electrical Signals in a Heart

Modeling the electrical activity in cardiac tissue is an important step in understanding the patterns of contractions and dilations in the heart. The heart produces rhythmic electrical pulses, which trigger the mechanical contractions of the muscle. A number of heart conditions involve an elevated risk of re-entry of the signals. This means that the normal steady pulse is disturbed, a severe and ...

### Electric Sensor

This is a model from electric impedance tomography, a method of imaging the interior permittivity distribution of a body by measuring current and voltage at the surface. This model demonstrates how the shape and placement of figures with different material properties inside a closed box can be determined with this non-invasive technique. Applying a potential difference on the boundaries of ...

### Vacuum Drying

Vacuum drying is a chemical process frequently used in the pharmaceutical and food industries to remove water or an organic solvent from a wet powder. When designing a vacuum drying system, engineers aim to minimize the drying time while maintaining high quality in the product. This model investigates vacuum drying in a Nutsche filter-dryer, which consists of a cylindrical drum filled with wet ...

### Eigenvalue Analysis of a Crankshaft

This model describes a modal analysis of a crankshaft. The pistons’ reciprocating movement is transferred to the crankshaft through connecting rods by means of crankshaft throws. The forces, torques, and bending moments, which are highly variable both in time and space, subject the crankshaft to very high and complex loading. The crankshaft design must therefore incorporate careful and ...

### Automotive Muffler

This model simulates the pressure wave propagation in a muffler for a combustion engine. It uses a general approach for analysis of damping of the propagation of harmonic pressure waves. The model is solved in the frequency domain and provides efficient damping in a frequency range of 100-1000 Hz.