Structural Mechanics Blog Posts

Starting Small with Sonar Dome Design
Starting the design process by testing on a small scale is often the best way to tackle issues affecting large objects, like a ship. Detailed in COMSOL News 2013, researchers at INSEAN, The Italian Ship Model Basin, used small-scale testing and then simulation to analyze the effect of placing a sonar system within the bulbous bow at the hull of a ship. Using a small-scale model of a bulbous bow, the researchers at INSEAN performed fluid-structure interaction experiments, and subsequently […]

Modeling Magnetostriction Using COMSOL Multiphysics®
If you have ever stood next to a transformer, you have probably heard a humming sound coming from it and wondered if there were bees close by. When you hear that sound the next time, you can rest assured that it’s not bees but the magnetostriction of the transformer core that is making that humming sound.

Turbine Stator Blade Cooling and Aircraft Engines
Technology and mechanics enthusiasts might agree that engines are very cool — and they also know how fussy they get when running into cooling problems. When it comes to aircraft propulsion, overheating is not an option. Most planes can’t fly safely without an engine, so why run the risk of overheating? While current engine designs limit that risk using clever cooling systems, another path to solve this problem would be to design more energy-efficient engines, exempt from excessive heat release. […]

Analyzing Electrical and Thermal Conductance in a Contact Switch
A contact switch is used to regulate whether or not an electrical current is passing from a power source and into an electrical device. These switches are found in many types of equipment and they are used to control, for example, the power output from a wall socket into a device when it is plugged in; the currents passing across the circuit board of a computer; or the electricity powering a light bulb when the switch is flipped on. Because of their […]

Fatigue Prediction Using Critical Plane Methods
Research on fatigue started in the 19th century, initiated following failing railroad axles that caused train accidents. In a rotating axle, stress varies from tension to compression and back to tension in one revolution. The load history is simple because it is uniaxial and proportional. Fatigue can then be evaluated with the S-N curve, also known as the Wöhler curve, which relates stress amplitude to a component’s life. In many applications we deal with multiaxiality and non-proportional loading. In this […]

Simulating an Engine Governor, the Spring Loaded Centrifugal Governor
We’ve probably all seen centrifugal force in action in one way or another, whether it be riding on a merry-go-round as a child, spinning a bucket of water upside and observing as the contents hug the insides of the bucket, or watching mud spinning off of a turning tire. In addition to making dizzying carnival rides, this force can be used in the design of many mechanical applications, where it is harnessed to control a variety of effects. One such […]

Aircraft Landing Gear Mechanism Analysis
Aircraft rely on landing gear in order to taxi, take off, and land. The landing gear of your average commercial airplane consists of a shock-absorber cylinder and piston, and a pair of tires. Intuitively, the shock-absorber experiences stresses as the landing gear touches the ground — but how much? In order to design a landing gear mechanism that can withstand many landings, and to determine when it’s time to swap out an old one, we can perform a multibody dynamics […]

Modeling a Helicopter Swashplate Mechanism
A swashplate mechanism, used in a helicopter to control the pitch of the rotor blades, can be easily simulated using the Multibody Dynamics Module available in COMSOL Multiphysics. This module enables simulation of an assembly of flexible and rigid bodies, together with physical phenomena from fluid, heat, and electrical applications, among others. Here, we will show you a model to convey how a swashplate mechanism works and at the same time analyze the stresses and deformation in the flexible rotor […]