Structural & Acoustics Blog Posts
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 […]
Acoustics Tutorial for Modeling Organ Pipe Design
The way the sound is shaped as it passes through the pipe of an organ is the result of a carefully calculated and intricate pipe design. Browsing through the Model Gallery, I came across a model of an organ pipe, and it happens to be a great acoustics tutorial for using the Pipe Acoustics, Frequency Domain interface in COMSOL Multiphysics. Let’s talk organ pipe design, and walk through how we can model it with multiphysics software.
Can You Use Heat Transfer to Predict Migration of Contaminants?
The flow of fluid through a porous medium is usually described by Darcy’s Law. However, what if you wanted to look at a combination of fluid flow, heat transfer, and mass transport in a porous medium? Instead of using Darcy’s Law, which calculates an average linear velocity for fluid flow in porous media, the Navier-Stokes equations would be necessary in order to obtain accurate results. In addition, heat convection and conduction, as well as mass transport would need to be […]
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 […]
Simulating Plate Heat Exchangers
It’s not always obvious what a major role temperature control plays in modern technology, as the interchange happens in the background. Plate heat exchangers, made up of successions of metal plates and various coiled pipes, regulate and manipulate temperature, and they get the job done quickly — thanks to an active surface that is large with respect to their volume.
A Multidisciplinary Approach to Electronics Design
Sharp is a powerhouse in the electronics industry, involved in televisions, liquid crystal displays, LED lighting systems, solar cells, multi-function business machines, and many other electronics-based products. One of a global network of Sharp R&D laboratories, Sharp Laboratories of Europe (located in Oxford, England), has been busy researching and developing LED lighting, display technology, microfluidic lab-on-a-chip, and energy systems for incorporation into Sharp’s products.
Thermal Analysis Measures Blistering Heat
If you roast a turkey for dinner and you need to check the temperature, the technology exists to find it. But what happens if the temperature is so hot that a consumer-grade thermometer, or any man-made device, really, would instantly melt and be destroyed? This might not be a common occurrence in your kitchen, but it is a real concern in blast furnaces, where temperatures can reach close to 1,500°C. Simply guessing is far from safe. Luckily, by simulating with […]