Von Mises Stress
“How can we more accurately predict an object’s failure?”
One of the most important duties of a design engineer is to ensure that objects do not fail. However, classical failure theory does not always suffice. Instead, we must use more advanced concepts. One example of this is the Von Mises Stress, which is characterized by a superposition of all of the stresses on the object. If the Von Mises Stress is greater than the yield stress, then failure will occur. The formula for Von-Mises Stress is given by sigma_v = sqrt (sigma_1^2+sigma_2^2+sigma_3^2-sigma_1*sigma_2-sigma_2*sigma_3-sigma_1*sigma_3), where sigma_v is the Von Mises Stress and sigma_1,sigma_2, and sigma_3 are all stress superposition values. The Von Mises Stress can be visualized as an ellipse in 2 and 3 dimensions.
Copper in Renewable Energy Transmission
“What role does copper play in renewable energy transmission?”
Unless you’ve been living under a rock, you would know that renewable energy such as solar and wind are rising at catastrophic rates. And with this rise comes the need to safely, efficiently, and cleanly transport all of this energy. So how can we use our engineering mindset to solve this problem? Well, if we think back to fundamental principles, we know that the type of conductor used for transmission will greatly affect how electricity is expended. So logically thinking, we should use a material that does not lose much current to friction. A perfect candidate for this would be copper, due to its high conductivity and plentiful supply.
A Device to Pull Water Straight From Thin Air
“Is it possible to pull water straight from thin air?”
Water is one of the most vital components to many natural and industrial processes, whether it be keeping humans hydrated, running HVAC systems, or growing food. However, in many desert areas, water is extremely hard to come by. So how can we use our scientific mindset to solve this problem? Well, a team of chemists at UC Berkeley and MIT recently used a class of porous materials known as metal-organic frameworks to build a sheet that can absorb water vapor during the night, hold it during the day, and use the sun’s rays to release some vapor and siphon it to a condenser to create usable water! This system uses 3 liters of water per day for every kilogram of sponge-like absorber it contains and holds much promise to revolutionize access to basic drinking water.
The Problem with Battery-Powered Planes
“What do we need to overcome before we make battery-powered planes?”
Although promising, battery-powered planes have a major hurdle to overcome before they make any major traction. As it stands, electrochemical batteries have only 1/60th the energy density of conventional plane fuels. This is further compounded by the fact that such batteries are heavier to equip, meaning more weight on the aircraft and a reduced ability to fly. However, if we can overcome these problems, whether it be through a new type of battery or improved electrical motors, then battery-powered planes are poised to disrupt the entire aviation industry!
“How do metals waste away with time?”
Metals are some of the most widely used materials in the world. However, nothing within the realm of physics lasts forever. If a metal is immersed in an atmosphere, then it will be surrounded by chemicals alien to its own. Chemical reactions are bound to occur, and over time this metal will decay and waste away in a process known as corrosion. Corrosion is a very important engineering factor, especially for public infrastructure. So much so that in 1998 alone the total annual direct cost of corrosion in the U.S. was around. $276 billion!
“Why do tongues work?”
One of the most fascinating facets of the human body is the tongue. Its ability to move food around in one’s mouth without any bone structure is quite marvelous. However, how exactly can it do this? Well, let’s use our scientific mindsets to find out. If we analyze our tongues further, we should see that these appendages are in fact in fact constructed of muscular material. Because of this, they have an inherent flexibility where any region of the tongue can lengthen, shorten, twist, or bend at any time, allowing for a wide arrange of movement. These Muscular Hydrostats can be found in many other animals, such as the tentacles of octopi and the Trunks of elephants. Because of their diverse applications in the animal world, engineers are researching how to implement similar materials into robotics systems
How cement is made
“How is cement made?”
Cement is one of the most versatile materials on the planet. However, how exactly is it made? Well, let’s use our engineering mindset to find out. First, we must gather up its primal ingredients: limestone, clay, and others. Then, we must crush these rocks. Then we must combine this crushed material with other ingredients such as iron ore and feed it into a cement kiln. The kiln will then heat all of these ingredients, burning away some, and producing a red-hot compound known as clinker. This clinker must then be ejected into a cooling plant, and be mixed with gypsum and limestone to eventually form the cement that we know and love.