All posts by Alexandra Foley
Wilkinson Power Divider Simulation
A Wilkinson power divider is a common three-port power splitter circuit that is used to split an input signal into two equal output signals, or to combine two signals into one. Unlike resistive or T-junction power dividers, a Wilkinson power divider allows for nearly complete isolation between the two ports and adds no resistive losses to the power split. Because of these characteristics, a Wilkinson divider is widely used in radio communication systems due to its ability to prevent crosstalk […]
Veryst Engineering Simulates LED Lighting Designs
Last month, COMSOL Certified Consultant Veryst Engineering was featured in Software Tech Briefs, a special supplement to NASA Tech Briefs. Veryst is known to leverage multiphysics simulation software for analyzing LED lighting designs and other complex industrial problems. The project mentioned in the article focused on building a thermofluid-mechanical model of an LED light bulb in order to explore and optimize thermal management techniques within the bulb.
Integrated Circuit Design and the Photolithography Process
When designing products on the nanometer scale, physics interactions that are considered negligible on the larger scale make their presence known. One such case where these forces must be taken into account is in the design of integrated circuits, where understanding and optimizing the effects of van der Waals forces, attractive forces, and surface tension become vitally important to creating a robust design. As technological advancements call for both the size of integrated circuits to decrease and the density of […]
The Advantages of Mechatronic Simulation at KOSTAL
For 60 years, the technology manufacturer KOSTAL Group has been implementing various electrical systems in cars, making your driving experience more enjoyable. For instance, the Automotive Electrical Systems division of KOSTAL placed indicator switches near the steering wheel and created integrated-function push buttons. Over the years, their patents and designs have become more complex and revolutionary. Currently, they are working on optimizing the design of their roof modules for premium cars using mechatronic simulation.
Simulating Tensile Stress in a Tube Connection with Prestressed Bolts
When analyzing a bolted joint, one thing to consider for an accurate analysis is the bolt pretension. With COMSOL Multiphysics, the effects of prestressing a bolt can be easily computed using the Bolt Pre-tension feature available in the Structural Mechanics Module. After modeling prestressed bolts, a further analysis can then be conducted on an external load applied to the structure. Here, we will explore how to include prestressed bolts in a tube connection model, and then carry out a stress […]
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 […]
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?
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 […]
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. […]
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 […]
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.
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 […]
Density-Driven Fluid Flow in Porous Media
There are many different forces that can induce flow in fluids, such as kinetic energy, pressure gradients, concentration gradients, and many more. In natural systems, one effect that can initiate fluid flow in a still fluid is a change in density. This density change will result in a change in the fluid’s buoyancy, thus inciting flow as the denser fluid sinks and the less dense, buoyant, fluid rises. You’re probably most familiar with these changes in density occurring due to […]
Simulating Thermal and Electrical Stresses in Medium Voltage Cables
Underground medium voltage cables are often used to deliver electrical power from a transmission system and into the home of consumers. In the United Kingdom, these cables carry hundreds of amps at voltages between 11 and 33 kV, a typical voltage of electrical transmission cables around the world. Analyzing the stresses that these cables are exposed to over their lifetime is important for ensuring both consumer safety and energy efficiency. Researchers from the Glasgow Caledonian University in Scotland used COMSOL […]
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 […]
CFD Applied to Two-Phase Flow, an Italian Dressing Simulation
The fact that oil and water don’t mix is something that you are probably all familiar with. At one point or another, you’ve most likely noticed what happens when you shake a bottle of say, Italian salad dressing, and the liquids mix momentarily, only to become separated again within seconds as oil bubbles rise to the surface. Creating a simulation describing how these two immiscible fluids interact is a great way to introduce computational fluid dynamics (CFD) applied to two-phase […]
A Recipe for Induction Stove Design Using Multiphysics Simulation
When I was little, I used to love spending the night at my grandparents’ house, where I was allowed to watch TV, stay up late, and in the morning, help my grandmother make pancakes. The hardest part was always waiting for her old, slow electric burner to heat up — to my six-year-old self, it seemed to take hours for the burner to become hot enough after we’d finished mixing the batter. Luckily for me, and for other impatient chefs […]
Water Purification Using Ozone
Water purification is the process by which chemicals, contaminants, and sediments are removed from dirty water to make it clean, and there are many processes through which this can be done. What you might not know, is that ozone molecules can be used as a means of disinfection in the purification process. “Ozonation” has been used to purify water, kill germs and bacteria in food, and even get rid of bad smells. Not only does ozonation provide clean water without […]