Author: Isaac Gendler

Carnot efficiency

Carnot efficiency

04/28/17

“How can we calculate the maximum efficiency of a heat engine?”

Due to the second law of thermodynamics, physics proves that there is a limit to the efficiency of all heat engines. However, we know that from practical experience that some heat engines are more efficient than others. So how can we predict what the maximum efficiency of a heat engine can be? Well, engineers and physicists have thought about this same problem for many long years, and after deep exploration into the subject an equation known as the carnot efficiency has been fabricated. This equation states that the maximum efficiency of an engine is the difference between the maximum temperature and the minimum temperature divided by the max temperature, or that (nu) = (T_max-T_min)/t_max. As a result, the efficiency can never be greater or equal to 100%, and if there is no difference in the temperature the maximum possible efficiency is 0%

Heat engine theory

Heat engine theory

04/27/17

“How can we turn heat into useful energy?”
It is a well-known fact that energy can be converted into heat. However, is it possible to accomplish the opposite? Well, let’s think about it. We know that if we connect two points with different temperatures, then a heat flow will take place. And since this means that there is a transfer of energy, it can be redirected into useful work. A machine that accomplishes this is known as a heat engine, which is used in everyday life from jet engines to electricity generators.

Driving cycle

Driving cycle

04/26/17

“How do engineers analyze the speed of an automobile?”
The Automobile is one of the most omnipresent devices on the planet. And as such, when being analyzed, all studies must be done with great precision. So how can engineers look at one component, velocity, with extreme detail? Well, thanks to the hard labors of many researchers, a tool known as the drive cycle has been developed. In essence, a drive cycle is a collection of data points representing a vehicle’s velocity in contrast to time. This system is often used by engineers to estimate the amount of fuel that a car has used since a car operating at higher speeds will burn more petroleum.

Boilers

Boilers

04/25/17

“How can we use machines to heat up fluids?”
We use warm fluids in our lives every day, whether it be in the showers we take, the HVAC systems that make our homes cozy or in our electrical generators. However, how exactly can we heat up such fluids? Well, let’s use our engineering mindset to find out. We know that if left to the surroundings, the heat from a fluid will radiate out. So if we were to place this fluid into a container, then logically the heat would be trapped inside. Furthermore, let’s control the temperature of this fluid by placing the container near a combustible source as to constantly supply energy. After constructing this, we will have ourselves what engineers have termed a boiler. Such machines are vital to the operation of our infrastructure, whether it be in the engines of trains or for culinary purposes.

Magnetic attraction bearings

Magnetic attraction bearings

04/24/17

“How can we use magnetic attraction to make bearings?”

Conventional mechanical bearings are limited by the effects of mechanical friction which impinges their durability, speed, and control. However, by removing physical contact with the shaft, the bearing will become far more optimal. So how could we implement such an idea into reality? Well, one method is to use the physical mechanism of magnetic attraction to remotely control the bearings. Such magnetic attraction bearings would be freed from the limitations of traditional mechanisms and could provide for far more efficiency. However, due to chaotic nature of rotation, a self-centering device must be used with such mechanisms, so that no side becomes too close to the magnetic center and therefore lose balance. Such conundrums can be remedied with magnetic repulsion models.

V-6 engines

V-6 engines

04/23/17

“How can we make an engine with six pistons?”

Most non-American car models are powered by conventional four-piston engines. However, such technology can be slow and weak. So how could we create a new engine that would be faster and offer more powerful acceleration? Well, let’s use our engineering mindset to figure this out. We know that one of the bottlenecks of four-stroke engines is their limited stroking numbers. So what if we were to increase the amount of pistons active? Well, if we were to take six cylinders, put them at 60 degrees from the horizontal (to smoothen vibrational effects) and activated them, we would have an engine that is both compact and powerful. This configuration is known as a V-6 engine, and is used widely by American automobile manufacturers.

Exhaust gas

Exhaust gas

04/22/17

“Why do diesel engines vehicles cause pollution?”

Every day, you probably hear about how the levels of greenhouse gas concentration in the atmosphere are growing exponentially, and how much of that derives from the use of petroleum vehicles. However, why do such machines cause so much harm? Well, let’s use our scientific mindset to figure this out. Upon analysis, one would be able to obtain that the exhaust gas emitted by vehicles are composed of carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides, and hydrocarbons. These pollutants are potent greenhouse gasses, and can not only impinge upon the health of the atmosphere but the health of human society through the instigation of smog and other health hazards.

Desalination plants

Desalination plants

04/21/17

“How can we make saltwater drinkable for humans?”

Humanity is running into a problem. With each year our water supplies are getting lower and lower. Soon enough, we may not be able to provide ourselves with one of the most basic components of life.

But does it have to be this way?
If we apply our engineering mindsets, then we can devise a method for water purification to sustain our livelihoods. To begin, let’s start out with some simple chemistry. 96% of the water on this planet is stored in oceans as salinated water. And because of its salty nature, by default, it is unsafe for human consumption. However, we must take one more fact into consideration, that the evaporation point of liquid water is lower than that of salt. So what if we used some simple logic and create a device that would heat salt water up until the point of evaporation, move it over into another container, and then condense it into drinkable water? Well, this is the fundamental idea behind a system which engineers have termed desalination plants, and are used to treat saltwater around the world. One downside of traditional desalination plants is the vast amount of energy required to heat up the water, taking around 5 kWh for a cubic meter of just fresh water!

Aeroponics

Aeroponics

04/20/17

“How does NASA grow plants suspended in the air?”

With the advent of hydroponics, the roots of plants have been liberated from the soil, allowing for far more sustainable agricultural systems to develop. One of these methods actually involves suspending the roots of the plant in the air and then filling the environment with a nutrient mist. Scientists have termed this process aeroponics, and allows for a higher density yield and allow for the roots to more efficiently absorb oxygen. However, one drawback is that this system must be constantly sprayed with a 35% hydrogen peroxide to prevent the spread of impinging fungi and bacteria. NASA uses aeroponic systems to grow food for astronauts on year long missions.