Latest Posts
Why Does a Microwave Heat Food Unevenly?
It’s probably something we have all experienced. We get home, stick last night’s leftovers in the microwave, and sit down to have a nice meal — only to realize that the food is scalding hot one bite and freezing cold the next. This experience has prompted me on more than one occasion to wonder: Why does a microwave heat food so unevenly?
Skimboard Hydrodynamics: It’s All in the Boundary Conditions
When it comes to recreational water sports, simulation can make a dramatic difference in performance. Skimboards are a perfect example of this. These short, thin boards are similar to surfboards without fins and they allow riders to float on the water’s surface and glide. In order to improve the design of the board, one group of researchers relied on hydrodynamics to understand the interaction between water and skimboards.
Fractals, Beyond Eye Candy
Fractals are those exotic mathematical entities whose geometric properties fall between integer dimensions (1D, 2D, 3D). Space-filling curves and bounded sets with infinite perimeters fall into this category.
Modeling Flow: Heat Exchanger Microchannels
Plate heat exchangers have a larger surface with respect to their volume as compared to a conventional shell and tube design, making for an efficient temperature regulation device. As the name infers, these types of heat exchangers consist of layers of corrugated metal forming channels in between. In order to optimize their performance, you need the flow through the channels to be well-distributed. As you can imagine, the flow is very detailed and modeling it can be computationally demanding, if […]
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.
Modeling an Accurate Drug Delivery Device
There are many different routes through which drugs and other medications can be delivered into a patient’s body during treatment. These include topographical ointments, pills, vaporizers, and injection systems, among others. Many of these drug delivery systems require an enormous amount of precision when it comes to the location, timing, concentration, and amount of the drug to be administered. This is where simulation can be a big help, as it can allow for the modeling of each of these aspects […]
Efficient Solar Panel Design Improves the PV Industry
Solar photovoltaic (PV) cells are semiconductor devices that directly convert solar energy into electricity or voltage using the photovoltaic effect. These PV cells are more commonly known as solar cells, or solar panels, and in 2012 they produced roughly 93 terawatt-hours (TWh) of electricity — enough energy to power over 20 million homes. Because the cells must be directly exposed to the sun’s rays, they are housed outdoors where the panels are affected by the elements. Therefore, the cells must […]
Innovative Microfluidic System for Cooling Windows
The same window that allows natural light into your home also brings about an increase in your air-conditioning bill. While certain measures have been taken to improve the energy efficiency of windows, they still account for a large portion of buildings’ energy costs. As unfavorable as that is, we ultimately want our buildings to have windows, and tend to accept the sunlight in/energy bill up trade-off. However, advancements are currently underway to improve this trade-off by lessening the energy charges […]
Learn About Structural Corrosion Modeling from NRL
Structural corrosion modeling has long been considered a tough problem to solve. The combination of coupled physics effects and metal shape change pose quite a computational challenge. Fortunately, engineers have found that multiphysics software brings a solution. A great example of this is coming up at the COMSOL Conference 2013 Boston this fall, when Dr. Siddiq Qidwai from the Naval Research Laboratory will take the stage and let us in on how to properly model structural corrosion.
New Approach to Electronics Cooling Using a Corona Discharge
You may be familiar with the humming start of the mechanical fan that turns on when booting up your laptop computer. Such a fan is necessary to prevent electronic devices from overheating, and the accompanying whirring sound of the cooling system is an unavoidable side effect. As electronic devices become smaller, this mechanical fan must decrease in size as well, and therefore spin faster and faster in order to deliver the same amount of heat dissipation as a larger fan. […]
Tuning an Orchestra with the Help of Multiphysics Simulation
Multiphysics applications are all around us. Consider, for example, a setting where science may be the last thing on our minds: a music concert. You might be enjoying the slight sinusoidal variations in atmospheric pressure we call sound waves, or music, but those pressure variations must come from somewhere. In fact, they are due to a multiphysics effect where sinusoidal structural vibrations in an object disturb the surrounding air, causing pressure variations in the air that then propagate outward and […]
Specific Absorption Rate (SAR) in the Human Brain
It seems everyone and their kid brother has a cell phone these days — and we are constantly using them. We don’t just rely on them to make calls anymore, either; they serve as our maps, calendars, to-do lists, channel for social interaction, and so forth. This continuous use begs the question: “What about the radiation our phones emit, and how much of it is absorbed by our brains?” When considering this, scientists use the specific absorption rate (SAR) to […]
Inertial Focusing, a Counterintuitive Approach to Concentrate Cells
Suppose we have a rectangular microchannel containing a laminar flow with Reynolds number Re = 1. Next, let’s randomly distribute suspended particles at the channel’s inlet. Given that there are no external forces acting on these particles, you would intuitively expect that the particles would trace the fluid streamline. However, scientists from Massachusetts General Hospital (MGH) and Veryst Engineering would disagree, and their research findings suggest a completely different pattern than what would be expected. The researchers claim that depending […]
Simulating Pesticide Runoff, the Effects of Aldicarb
When pesticides are used in crops to control pests, their effects on the environment continue even after they have served their purpose. Pesticides can leach into the soil and water sources that both humans and animals depend on, spreading harmful chemicals to the surrounding ecosystem. Over time, their active ingredients are detoxified through different reactions that occur after their release, eventually degrading them into harmless products. Understanding the pesticide runoff patterns and mobility of various pesticides before and after they […]
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. […]
How to Implement a Mesh Refinement Study
A couple of weeks ago, I led a webinar on postprocessing and visualization features in COMSOL Multiphysics. This webinar was very popular among COMSOL users, so I wanted to follow up with a blog post to highlight one of the important topics we covered — performing a mesh refinement study in COMSOL Multiphysics.
Lam Research on Simulation of Wafer Fabrication and Moore’s Law
We have come to take for granted the ever-increasing performance gains in computational power. Enabled by advances in semiconductor processing techniques, we reap the benefits from exciting new features in everything from smartphones to workstations. The good news for all of us is that the semiconductor industry is steaming ahead, relentlessly pushing the limits of wafer fabrication. Each year, a new generation of sophisticated fabrication equipment is developed. Features etched on silicon are now at the atomic scale. In the […]
Using Gradient-Free Optimization
The COMSOL Optimization Module includes both gradient-based and gradient-free optimization techniques. Whereas the gradient-based optimization method can compute an exact analytic derivative of an objective function and any associated constraint functions, it does require these functions to be smooth and differentiable. In this blog post, we examine the use of the gradient-free optimizer, which can consider objective function and constraints that are not differentiable or smooth. The dimensions of a spinning wheel are optimized to reduce the mass while maintaining […]
Simulating the Freeze-Drying Process
When thinking about freeze-drying processes, I am reminded of astronaut food like the freeze-dried ice cream I tried as a kid. While this application of freeze-drying is important for preserving food being launched into space, there is also an incredible number of noteworthy applications that are used a little closer to home. Let’s take a look at the freeze-drying process, how it can be simulated, and some of the products and designs that rely on it to function.
Using a Microfluidic Valve to Separate Charged Particles
When you think of a valve, what is the first thing that comes to mind? Electromagnetic waves, or perhaps, Stokes flow separating charged chemicals in a microchannel system? Maybe neither. The truth is, when researchers try to separate small (in the picoliters region), well-defined sample volumes of chemicals, the dispensing accuracy provided by a mechanical regulator probably won’t suffice. An electrokinetic valve, a type of microfluidic valve, on the other hand, provides the perfect solution by giving researchers the flow […]
Hear About Designing Efficient Appliances from Mieletec FH Bielefeld
In 1898, Carl Miele and Reinhard Zinkann founded the Miele company. Since then, it has grown into one of the world’s foremost producers of household appliances, including washing machines and cooking devices for both domestic and professional use. Miele has created a joint research laboratory, mieletec, with the University of Applied Sciences in Bielefeld, Germany. There, the foundations are being laid for the next generation of resource and energy efficient household appliances. This October, you have the chance to hear […]
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 […]
ETREMA to Talk About Transducer Design using Smart Materials
Julie Slaughter and her team at ETREMA Products are in the enviable position as the sole U.S. provider of the smart material Terfenol-D, and developer of products based on this material. Terfenol-D is said to produce giant magnetostriction that boasts strains 100 times higher than traditional magnetostrictive materials, such as iron. Just imagine the possibilities of applications harnessing this amazing material property. If you’re attending the COMSOL Conference in Boston this October, you will hear ETREMA talk about transducer design […]
Success Stories and Limitations of 3D Printing
From supporting research to creating custom prosthesis, what doesn’t 3D printing seem to promise these days? We all know 3D printing has arrived, and the technology is already being put into practice by companies and tech-savvy consumers everywhere. It seems there’s a new 3D printing success story published every day, and no matter how fascinating, it makes you wonder about the wider repercussions and limitations of 3D printing.