Latest Posts
Multiphysics versus FEA
In a popular post from last year, I discussed accessing and manipulating the underlying equations in COMSOL. This blog post instigated reader comments, and most of the respondents appreciated, or even required, the ability to look at the mathematical model (i.e., equations) behind the physics. While considering this, I realized that there is more to the story, and with a little perspective, the community could benefit from further discussion.
On Solvers: The V-Cycle Multigrid
As discussed previously on the blog, iterative methods efficiently eliminate oscillatory error components while leaving the smooth ones almost untouched (smoothing property). Multigrid methods, in particular, use the smoothing property, nested iteration, and residual correction to optimize convergence. Before putting all of the pieces of this proverbial puzzle together, we need to introduce residual correction and dive a bit deeper into nested iteration. Let’s begin with the latter of these elements.
Fluid Flow: Smooth Optical Surface in Minutes
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.
On Solvers: Multigrid Methods
Solution methods are a valuable tool for ensuring the efficiency of a design as well as reducing the overall number of prototypes that are needed. In today’s blog post, we introduce you to a particular type of method known as multigrid methods and explore the ideas behind their use in COMSOL Multiphysics.
Infamous Failures of Fatigue
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 […]
Corona Discharge
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.
Electroplating Simulations Cut Down on Wasted Metal
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. […]
Injectable Microbubbles in Hydrology and Healthcare
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.
Joule Heating Simulations Tutorial
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 […]
What is Efficiency?
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.
SolidWorks World: Human Space Flight and Autonomous Flying Robots
SolidWorks always puts on a great show. I just got back from SolidWorks World where I was able to go to a number of technical sessions, and understand how CAD design can better complement finite-element analysis. We had a booth there, and it was great to meet a few COMSOL users, who like to use SolidWorks® and COMSOL Multiphysics together via LiveLink™ for SolidWorks®. I also got to meet potential customers-to-be. In typical SolidWorks World fashion, I and the other […]
Non-Newtonian Fluids, Between Solids and Fluids
One of my favorite sitcoms is “The Big Bang Theory”, thanks to its focus on physics. From time to time they run funny experiments that can be easily arranged at home, causing me to wonder if I know the physics that are at work. One of my favorite episodes is when they fill the cone of a speaker with a suspension of starch in water. Instead of spattering around, the suspension starts to dance because it behaves more like a […]
Modeling Lithium-Ion Battery Cooling
Get a brief introduction to creating a lithium-ion battery model using the COMSOL Multiphysics® software in three sequential studies. At the end of the blog post, there is a link to download the tutorial model.
The Science of Cooking, Multiphysics meets Food
It’s that time of year again for all the foodies out there; on January 29th the 2013 Bocuse d’Or will be in full swing with 24 chefs each representing their country, vying for the Gold Medal in the Olympic Games of the culinary world. In this biennial event, the chefs will have to combine classical and innovative cooking techniques to come out on top. At the last Bocuse d’Or in 2011, Gunnar Hvarnes propelled past the competition with the aid […]
Industry: Continuum Blue Simulates Structural Mechanics
On January 10th, hundreds of people tuned in to hear COMSOL and Continuum Blue discuss Structural Mechanics simulations in certain industry applications. As promised in my previous blog post on multiphysics modeling webinars happening in 2013, here is a round-up of the event — including a video excerpt detailing three structural analysis examples presented by Continuum Blue.
Video: Modeling Mechanical Applications
How do you avoid product failure down the line? By ensuring you manufacture accurate parts and assemble them correctly, of course. Manufacturing success stems from good design ideas. “Good ideas” are not conjured up at random; good ideas are those that are based on real-world physical principles. This video will show you how your company can infuse sound concepts into the early product development stages by modeling mechanical applications in COMSOL Multiphysics.
Gold Nanorods for Medical Treatment
Nanorods are synthetic nanoscale objects used in the area of nanotechnology. They can be synthesized from semiconducting materials or metals, such as gold. The applications of nanorods are many, ranging from display technologies and energy harvesting to cancer therapy.
Magnetic Shells Designed to Improve Energy Transfer
Engineers and scientists are known to step up to the challenges posed by nature. After developing an understanding of how the current object or process works, the next step often includes figuring out how to manipulate the situation to improve said object or process. One such example is cloaking; controlling light and sound waves to render something invisible. Phys.org recently ran a story on progressive research on controlling magnetic fields via cloaking to harvest and transfer energy using a magnetic […]
Researching Carbon Fiber Reinforced Plastic Acoustic Guitars
There are traditional acoustic guitars made of wood, and now there are also those made entirely out of carbon fiber reinforced plastic (CFRP). Do these plastic guitars sound like their wooden forbearers? Guess what, you can use computer modeling to find out.
Wind Turbines in Urban Settings a Reasonable Idea
If I asked you to envision a wind turbine, odds are you’d picture a wind farm in some remote location. With good reason; that’s commonly where they are found. If you’re a student or faculty of Case Western Reserve University, on the other hand, you might think of the wind turbine you have on campus. Does it make sense to set up wind turbines in urban settings? These two researchers suggest that it does.
Efficient Heat Exchanger, it’s all in the Pipes
Nature is full of counter-intuitive phenomena; I’m fascinated by everyday examples like the one we talked about this summer, sinking bubbles in a pint of Guinness, but I have to say that engineering has its fair share of such examples too. The concept of heat exchange in coaxial pipes struck me as a student, as it showed me the relentless tinkering attitude typical of engineers wanting to optimize their design. In this kind of heat exchanger both streams, hot and […]
Power Transistors and Heat Transfer
Transistors are building blocks of electronic appliances, and can be found in radios, computers, and calculators, to name a few. When working with electrical systems you typically have to deal with heat transfer; electric heating is often an unwanted result of current conduction. Is a heat sink mounting necessary to keep the transistor cool, or can it manage without? Let’s have a look at power transistors from a heat transfer perspective.
Is Fracking Safe? Scientists Turn to Simulation to Investigate
Hydraulic fracturing (popularly referred to as “fracking”) is a method to increase production of oil and gas from certain types of geological formations. It has been used for decades, but recently, as the practice has increased, fracking has become a controversial topic. I will avoid taking sides in this debate, but the fact that there is a conflict implies there needs to be a deeper understanding of the process and its effects.
Modeling a Pratt Truss Bridge
The simple design of a Pratt truss bridge makes it useful to hold everything from pedestrians to trains. While this type of bridge is easy to construct, engineers must make sure that it lasts and is safe to use. A bridge needs to hold its own weight, support the load placed upon it, and withstand frequencies generated by wind and earthquakes. To determine whether a Pratt truss bridge design can handle these factors, we turn to simulation.