In our daily lives, we are sometimes required to commute, the need for movement of people, animals, goods, and services to move from one point to another is as long as time itself. Right from the time of the beginning of time, man and beast have always needed to travel. The evolution of this has been very dynamic. Man has always sought to make his need to move to be as seamless as possible. From riding on horseback to chariots, ships, and even to the modern-day means of transport such as the airplane and the automobile, there has been a significant shift from rudimentary means of transport to more advanced means of transport.
One of the most prominent means of transportation is by road (popularly admitted as the most dangerous means of transport with some statistics going as far as saying 1.35Million people are killed every year) with the automobile being one of the most used equipment for road commute. Considering that there are about a 1.42Billion operational cars in the world daily, (1.06Billion being passenger cars and 363Million being commercial vehicles) it begs the question, how much do you know about the machine that you use every day?
I am naturally a curious person, right from my childhood, I have always questioned the “MIND BEHIND THE MACHINE”. No prizes for lucky guesses that I became an engineer, the calling was borne out of a desire to want to know more. On that note, let me shed some light on the machine most of us use every day called the AUTOMOBILE.
In 1886, a German inventor named Carl Benz patented bis Benz Motorwagen. A few years later, Ford motors closely followed with the model T in 1908. These were the first modern recorded automobiles powered by an internal combustion engine or ICE for short. There are two types of INTERNAL COMBUSTION ENGINES, the more commonly used one in passenger cars (especially in Nigeria due to the lower cost of petrol to diesel) is called the SPARK IGNITION ENGINE. The other type is called the COMPRESSION IGNITION ENGINE. Now, it is important to state here that there are subgroups under these broad categories, but I am sure you the reader will get the drift. Since we are not in an engineering blog, I will desist from being technical and try to make this read a bit more fun.
Spark ignition engines or SIE for short as the name implies use a spark created by a plug or some sort of spark system to ignite the mixture of air and fuel in the cylindrical chamber where something round called a piston moves up and down (for reference, the mixture of air and fuel is called a charge). This movement completes a combustion cycle and there are two types under the SIE engine. These are 2 stroke and 4 stroke. The cycles look similar when observed with the naked eye because they both involve the piston moving up and down. However, with close observation, they are entirely different. The 4-stroke cycle includes the suction or intake stroke, the compression stroke, the combustion or power stroke and the exhaust stroke.
The 2 stoke as the name implies is just two strokes, the intake and the power stroke. Simple, right? Well, there is not too much to the two-stroke cycle. The major difference in layman’s terms is that while the 4stroke engine goes through two complete revolutions, the two-stroke only does one.
Now, I would have opted to discuss the Compression Ignition Engine or CIE for short in my next post but let’s do a bit of it here. The CIE is a much more power-driven engine. It is like an engine on steroids, well, it is powered by a heavy oil called diesel and it generally can operate for longer. The basic way it works is by compressing the intake air –see that I did not mention charge was compressed here – that is the piston does the compression to superhot temperatures and ignition occurs with the fuel is injected at high pressure into the air. This causes an explosion, essentially, a very loud one (which you cannot hear outside) – insert laughing smiley -, this explosion in turn powers the engine.
I hope this is a fun read as it does not end here. There are so many fun things that go on in the mind of the machine we call automobiles and together, we will enjoy the ride.
God bless you the reader and God bless the Federal Republic of Nigeria!