Latest Posts
Using Global Equations: Modeling Room Air Temperature in a House
An interesting question came up the other day that I felt would make an excellent blog post since it allows us to discuss one of the very powerful, and often underutilized, features of COMSOL Multiphysics: the Global Equation. In this post, we will look at using global equations to introduce an additional degree of freedom to a model. This additional degree of freedom will represent something we do not want to model explicitly.
Thermoacoustics Simulation for More Robust Microphone Analysis
When performing an analysis on small-scale audio equipment, such as hearing aids, cell phones, and microphones, the obvious physical phenomenon that’s analyzed is pressure acoustics. However, there are other physics interactions that significantly affect these small devices, including electromechanical interactions and viscothermal losses. Most notably, thermoacoustics (the detailed modeling of acoustics including thermal conduction and viscous losses) is an often overlooked effect that can alter the results of a model. These effects are important in all devices with small length […]
Simulating Thermal Stress in a Turbine Stator Blade
We can leverage simulation software to understand and optimize component design. Every simulation relies on a model that is a representation of the reality that the application finds itself in. Modeling enables us to represent this reality with enough detail to receive relevant information about the particular application or component. Let’s have a look at a thermal stress analysis of the turbine stator blade model from our Model Gallery and investigate the effects of heat transfer and thermal stress that […]
Flying Under the Radar with Altran Group’s Stealth Antenna Design
The unique properties of radio frequency (RF) electromagnetic radiation enabled countless innovations in recent decades, including the development of radar systems. Depending on the frequency, RF radiation can travel through solid insulating structures, typical atmospheric conditions, clouds, and rain with only minimal losses allowing for its use over long ranges and in varied weather conditions. The aerospace and defense industries have expanded and progressed rapidly as a result of using radar systems for detection and classification tasks to determine if […]
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 […]
How to Model a Shell and Tube Heat Exchanger
Shell and tube heat exchangers are one of the most widely used type of heat exchanger in the processing industries (65% of the market according to H. S. Lee’s book, Thermal Design) and are commonly found in oil refineries, nuclear power plants, and other large-scale chemical processes. Additionally, they can be found in many engines and are used to cool hydraulic fluid and oil. There are a variety of different configurations for these heat exchangers, but their basic concept can […]
Fluid-Structure Interaction (FSI) using COMSOL Multiphysics
Today we have the pleasure of welcoming Nagi Elabbasi of Veryst Engineering as a guest blogger. Read on to see what this COMSOL Certified Consultant has to say about fluid-structure interaction. Two weeks ago I led a webinar on fluid-structure interaction (FSI) using COMSOL Multiphysics. FSI involves coupling between a deformable or moving structure and a surrounding or internal fluid flow. There is a growing number of engineering and scientific problems where a purely structural or purely CFD analysis just […]
Thermal Insulation with Bubbles is Better
As a nuclear engineer, I’ve attended many thermal engineering classes. Whereas I’ve enjoyed learning techniques to enhance heat transfer, I’ve also found fascinating those applications where it is important to reduce heat transfer using the right choice and combination of materials and shapes. The design of this is vital for many industries, including the building and aerospace industries. Lately, I came across an interesting example of thermal insulation in the most mundane of these things: clothing design. I had to […]
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.