Fluid | Posted on
February 11th, 2013 by
Andrew Griesmer
Ultra-precise optical components require blemish-free surfaces that often cannot be achieved by the machining processes that grind these components. Fluid jet polishing (FJP) is a new technology being developed by Zeeko Ltd to replace the hand polishing that was often required. With the help of COMSOL, Zeeko was able to create a product that polishes the optical components in only ten minutes instead of an entire day, and without waveforms.
Read more on: Fluid Flow: Smooth Optical Surface in Minutes
Tips & Tricks | Posted on
February 8th, 2013 by
Valerio Marra
The differential equations that describe a real application admit an analytical solution only when several simplifying assumptions are made. The insights we gain from this approach are still valuable, but are not enough to confirm that our design is efficient or reduce the number of prototypes needed to reach a complete understanding of our application. This is why numerical solution methods are so important to us. They have been developed to overcome such limitations and allow us to represent our equations, on a grid obtained by partitioning the domain representing our application, in matrix form as 
, where 
is the vector solution. Once we have determined 
and 
, all we have to do is to “find” 
. It is important to note that the matrix form, both for stationary and transient applications, is obtained by finding a linear approximation to our equations. Nowadays, several solution methods are available. Here we will explore the ideas behind multigrid methods available in COMSOL Multiphysics.
Read more on: On Solvers: Multigrid Methods
Mechanical | Posted on
February 7th, 2013 by
Fanny Littmarck
If you’ve studied structural mechanics you’re probably familiar with stories of planes falling out of the sky due to fatigue (no one wants to be the engineer who designed an airplane that crashed…). Jimmy Stewart made a famous movie about that, but different from the usual horror stories of fatigue is the accident in 1919 of a storage tank that burst in Boston, spilling molasses onto the streets at 35 mph (56 km/h). The Boston Molasses Disaster, as it’s referred to, is another one of many infamous failures of fatigue.
Read more on: Infamous Failures of Fatigue
Electrical | Posted on
February 6th, 2013 by
Phil Kinnane
In its natural state, air is a good insulator. However, if it’s adequately ionized, it can ultimately lead to “corona discharge”. What does that mean and why is it important? Let’s find out.
Read more on: Corona Discharge
Chemical | Posted on
February 4th, 2013 by
Fanny Littmarck
Electrodeposition is the process of making a substance adhere to an object through electrochemical reactions. Sometimes the substance is available in the solution form and other times it is a solid object too, and needs to undergo electrochemical reactions in order to dissolve into solution; often as part of the electrodeposition process. Electrodeposition can be an important part of the refining process of certain metals, such as copper, silver, and gold and is often referred to as electrorefining or electrowinning. Another form of electrodeposition is known as “electroplating”.
Read more on: Electroplating Simulations Cut Down on Wasted Metal
Chemical | Posted on
February 1st, 2013 by
Fanny Littmarck
Microbubbles filled with oxygen can be injected into contaminated lakes to restore the water quality. Typically, water is purified via water-treatment plants, but this microbubble technique is both inexpensive and more environmentally-friendly in comparison. As seen in a COMSOL News 2011 article, oxygen microbubbles are a researcher’s way of copying nature’s own self-restoration mechanism for cleaning contaminated lakes.
Read more on: Injectable Microbubbles in Hydrology and Healthcare
Electrical | Posted on
January 31st, 2013 by
Fanny Littmarck
Transformers are used to increase the voltage of an alternating current (AC) before moving it along the power grid via power lines. Since power lines lose energy through heating cased by electric currents, you can achieve more economical power transmission by transforming to a high voltage and low current. As a matter of fact, high voltage (HV) power transmission lines transmit portions of its power in the air surrounding it. Furthermore, as the current travels long distances through many transformer stages, small design-changes in transformers can have very large effects in overall power transmission. To show you how these design improvements can be made, we’re holding a webinar on transformer and inductor modeling together with IEEE Spectrum on February 7th.
Read more on: Webinar: Transformer and Inductor Modeling
News | Posted on
January 30th, 2013 by
Fanny Littmarck
Students at Ohio State University can take a course on numerical simulations in biomedical engineering with Richard T. Hart. In the course, they will learn how to use computer modeling to solve biomedical engineering problems. Hart is now providing anyone who is interested in this application area with three video tutorials from the course via the Ohio State University iTunes U page.
Read more on: In Silico: Numerical Simulations in Biomedical Engineering
Electrical | Posted on
January 29th, 2013 by
Fanny Littmarck
One of the classic multiphysics couplings in engineering and science is joule heating, also called resistive heating or ohmic heating. Some joule heating examples include heating of conductors in electronics, fuses, electric heaters, and power lines. When a structure is heated by electric currents, the device can reach high temperatures and either structurally degenerate or even melt. The design challenge is to remove this heat as effectively as possible. COMSOL eases these challenges by providing a specialized multiphysics interface for joule heating, allowing for quick and easy definition of the phenomenon and even includes the ability to model convection for removing the heat.
Here, we’ve produced a video resource for you to see how you can effectively simulate joule heating using COMSOL Multiphysics. The 2-chapter video tutorial demonstrates how to model the joule heating of a fuse, seeking to answer the question: “Will it blow?”.
Read more on: Joule Heating Simulations Tutorial
News | Posted on
January 28th, 2013 by
Valerio Marra
When I first heard about Carnot’s theorem, I was impressed with its simplicity. Yet, no matter the amount of hard thinking we put into the design of everyday heat engines, we will never reach the efficiency of a Carnot engine. Still, modern-day heat engines are still effective as they get us from point A to point B by car or truck.
Read more on: What is Efficiency?
