Calculating the Spectral Properties of an Optical Ring Resonator

Brianne Costa August 14, 2018

If you ever visit the extravagant dome within St. Paul’s Cathedral in London, be careful what you say. As Lord Rayleigh discovered circa 1878, the vaulted structure exhibits an interesting acoustics phenomenon: Whispers from one part of the dome can be clearly heard in other areas. Rayleigh called the effect a “whispering gallery”. Surprisingly, you can observe a similar effect in another field of science entirely: light waves traveling in an optical ring resonator.

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Brianne Costa July 31, 2018

The Oldroyd-B numerical model defines flow in fluids that exhibit complex viscoelastic behavior under strain, such as clay, toothpaste, oil, and polymer solutions. In a benchmark model of an Oldroyd-B fluid, the COMSOL Multiphysics® software and add-on CFD Module are used to solve the numerical model, the results of which have been validated by published research.

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Brianne Costa July 11, 2018

The word “turbocharged” is often used colloquially to describe increased speed, such as “turbocharged” coffee that energizes you faster than a regular cup of joe. Actual turbochargers also increase speed, but in combustion engines instead of your morning mug. Turbochargers operate via turbine-driven forced induction and often rely on hydrodynamic bearings for support. However, these bearings naturally include cross-bearing forces that cause negative damping and system failure. Using rotordynamics modeling, you can analyze how these forces affect turbocharger designs.

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Brianne Costa July 4, 2018

Multijet tubular reactors are used to manufacture polymers such as polyester. The turbulent flow that occurs in this type of reactor can affect the manufacturing process, including the reaction kinetics, fiber quality, conversion, and yield. By developing a reactor model that fully takes into account both the fluid dynamics and chemical reactions, you can optimize a reactor design for efficient and reliable polymer production.

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Brianne Costa July 2, 2018

What do beer fermentation, soil analysis, and the production of dairy products have in common? They all involve the use of ion-sensitive field-effect transistors (ISFETs) for pH measurement. These sensors are small, efficient, and durable, which makes them suitable for food, environmental, and biomedical applications. However, ISFETs can experience drift and are sensitive to different temperatures, which limits their accuracy and stability. Using the COMSOL® software, engineers can accurately analyze ISFET designs and improve their performance.

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Brianne Costa June 25, 2018

In the 1998 song “This Kiss”, country singer Faith Hill describes the way she feels for the person she loves as “centrifugal motion”. Either Hill wants to get away from the song’s subject ASAP or she mixed up the term centrifugal with centripetal. We’ll forgive the 20-year-old song’s inaccuracies — besides, understanding the effect of centrifugal force is more important when designing components in a wide range of industries, such as centrifugal pumps for automotive applications, than in songwriting.

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Brianne Costa June 14, 2018

After World War II, a boom in the economy caused Americans to buy a record number of cars (leading to serious levels of pollution). Today, we have more energy-efficient vehicles — such as hybrid and electric options — and another “boom” is occurring, this time for autonomous vehicles (AVs). Again, pollution is an issue, but in a different way: There’s a debate over whether self-driving cars should have hybrid engines to maximize profit or all-electric engines to minimize pollution.

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Brianne Costa May 29, 2018

The Doppler effect, or Doppler shift, occurs when the movement of an observer relative to a source (or vice versa) causes a change in wavelength or frequency. Discovered by Austrian physicist Christian Doppler in 1803, this phenomenon is experienced in many different ways, such as when an ambulance passes you by and you hear an audible change in pitch. Using the COMSOL Multiphysics® software, you can model the Doppler effect for acoustics applications.

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Brianne Costa May 24, 2018

Some inventions haven’t changed much since they first came about…even if centuries have passed. For instance, the pop-up toaster was invented in 1921, and although enhancements have been made, it still toasts bread. Paperclips hit the market about 150 years ago and they still hold sheets of paper together. The same is true of the lead-acid battery, a device that was invented in 1859 and operated under the same basic principles as the one currently in your car.

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Brianne Costa May 11, 2018

Shape memory alloys (SMAs) are alloys with “memory”: They can return to their original shape after being deformed via a change in pressure or temperature. SMAs are used in a wide variety of applications — including metallurgy, manufacturing, biomedicine, and children’s arts and crafts — and their uses are always expanding…

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Brianne Costa May 9, 2018

During his life, John Scott Russell chased his passion for science — literally. While watching horses pull a boat through a shallow canal, he noticed a wave behaving strangely and followed it for one or two miles on horseback. For the rest of his life, he continued to chase this wave (which he called the “wave of translation”) figuratively, persevering even when his theories were ridiculed by scientists. Did Scott Russell ever catch up to his wave?

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