An Intro to Engines

The advent of engines transformed the human race’s relationship with the environment in which we find ourselves. There can be no doubt that the technological revolution that begun with the industrial revolution and continues in the present could not have progressed as it has without the engine. In its broadest practical definition, an engine is a human designed and manufactured machine that converts one form of energy into usable mechanical force. This mechanical force is then subsequently used to do work, in one form or another. The ability to convert energy from one form into another for the purposes of work has enabled us to traverse significant distances in just a few hours; similarly it allows us to transport ourselves effortlessly within our cities. In addition to the above benefits, engines play a direct role in generating the power used to produce goods for consumption and use.

Our understanding of engine design and efficiency has, in the time period of about a century, taken us from producing “horse-less carts” (the first cars/automobiles) to rockets that can produce enough thrust to free themselves from the earth’s gravitational pull and enter into space. At the same time, however, and unfortunately, progress in terms of engine capability has also increased the human race’s ability to wreak destruction upon itself: without engines, intercontinental ballistic missiles would cease to exist, and so would the means of effectively delivering nuclear devices via air or ground travel. In everyday life, however, engines are more important to a prospective buyer looking for used cars for sale than to armed forces.

Just as energy is used for the production of usable mechanical force, so too can mechanical force be used to generate other forms of energy. This is the exact principle inherent in most forms of electricity production: that is, the mechanical force of a rotating turbine generates electricity via electromagnetism. If the turbine is driven by super-heated steam, the energy conversion process can be divided into three essential stages: the first stage is when heat energy, produced by the burning of fossil fuels or even as a by-product of a nuclear reaction, causes water molecules to break free from their liquid bonds and enter into gaseous form. The rising steam is subsequently used to turn a turbine, transforming heat energy into mechanical force. These first two stages are informed by the basic principle of an engine; the final stage converts mechanical force into yet another form of energy: electricity.

Electromagnetic induction occurs when a magnet (with its own magnetic field) is moved through the magnetic field of another magnet. Each magnet has a conductive material wrapped around it, which allows for current to pass through a circuit. In the case of an engine that is used to drive a vehicle, the mechanical force produced by it is transformed into kinetic energy and, usually, heat energy.

The by-products of this type of energy production are, regrettably, often toxic to the environment and detrimental to animals (including humans). The carbon dioxide created by the burning of carbon based fossil fuels is widely regarded as being the major contributing factor to an increase in temperature in the earth’s atmosphere. The next time you fly from Jo’burg or Cape Town to view the property for sale in Bloemfontein or attend a business meeting etc., remember that the mobility afforded to you is at significant environmental cost.

It would seem as if global warming is the price humanity is paying for the prolific development of technology since the inception of the modern era (beginning with the industrial revolution), and the focus for technologists and the sciences to find ways of meeting energy demands in a cleaner, more environment friendly way.