Galleria dei Modelli
Cylinder Roller in Contact: A Benchmark Study
Consider an infinitely long steel cylinder resting on a flat aluminum foundation, where both structures are elastic. The cylinder is subjected to a point load along its top. The objective of this study is to find the contact pressure distribution and the length of contact between the foundation and the cylinder. An analytical solution exists, and this model includes a comparison against the ...
Fluid-Structure Interaction in Aluminum Extrusion
In massive forming processes like rolling or extrusion, metal alloys are deformed in a hot solid state with material flowing under ideally plastic conditions. Such processes can be simulated effectively using computational fluid dynamics, where the material is considered as a fluid with a very high viscosity that depends on velocity and temperature. Internal friction of the moving material acts ...
Thermal Stresses in a Layered Plate
The thermal stress in a layered plate is studied in this example. A plate consisting of two layers, a coating and a substrate layer is stress and strain free at 800 degrees C. The temperature of the plate is reduced to 150 degrees C and thermal stresses are induced. A third layer, the carrier layer, is added and the thermal stresses in the coating and a substrate layer are added as an initial ...
Peristaltic Pump
In a peristaltic pump, rotating rollers squeeze a flexible tube. As the rollers move along the tube, the fluid in the tube follows the motion. The main advantage of the peristaltic pump is that no seals, valves or other internal parts ever touch the fluid. Due to their cleanliness, peristaltic pumps have found many applications in the pharmaceutical, chemical, biomedical and food industries. ...
Viscoelastic Structural Damper
Damping elements involving layers of viscoelastic materials are often used for reduction of seismic and wind induced vibrations in buildings and other tall structures. The common feature is that the frequency of the forced vibrations is low. This model studies a forced response of a typical viscoelastic damper. The analysis involves two cases: a frequency response analysis and a time-dependent ...
Nonlinear Magnetostrictive Transducer
Magnetostrictive transduction is used in sonars, acoustic devices, active vibration and position control and fuel injection systems. The transducer has a steel housing enclosing a drive coil. A magnetostrictive material is placed in the core which works as an actuator when a magnetic field is produced by passing a current through the drive coil. Magnetostrictive material exhibits free strain ...
Two-port Piezoelectric SAW Device
This tutorial shows how to model surface acoustic waves in time domain. The 3D modeling geometry represents a 128 degree YX-cut lithium niobate substrate. The SAW device has two ports. The metallic electrodes are modeled as perfect conductors using boundary conditions. The geometric dimensions such as size of substrate, the gap between the ports and the number of inter-digitated electrodes (IDTs) ...
Surface Resistor: Thermo-Mechanical Analysis
The drive for miniaturizing electronic devices has resulted in today’s extensive use of surface-mount electronic components. An important aspect in electronics design and the choice of materials is a product’s durability and lifetime. For surface-mount resistors and other components producing heat it is a well-known problem that temperature cycling can lead to cracks propagating through the ...
Viscoelastic Material Model
Viscoelastic materials have a time-dependent response, even if the loading is constant. Many polymers and biological tissues exhibit such a behavior. Linear viscoelasticity is a commonly used approximation, where the stress depends linearly on the strain and its time derivatives. For many materials, the viscoelastic properties have a strong dependence on the temperature. A common assumption is ...
Thermal Expansion in a MEMS Device
This model analyzes the thermal expansion in a MEMS device, such as a microgyroscope, where thermal expansion should be minimized. The device is made from the copper-beryllium alloy UNS C17500 and uses temperature-dependent material properties from the Material Library. The purpose of this model is to exemplify the use of the Material Library in COMSOL Multiphysics. This library contains more ...
