Working of Turbochargers!

Hi Guys,

After a long time, I’m going to write a technical article. It is going to be a long series of articles related with Mechanical Engineering. My aim is that by reading these posts, common people should be able to learn something. So, let me write about Turbochargers today.

PC Game Freaks must have come across this word, while playing race games such as Need for Speed. Well, what is Turbocharger? Turbocharger is a device used to boost up the engine performance. It was earlier used in race cars, but these days it has become too common.

Before looking into Turbochargers, let us see the basics of a four stroke engine. It is the engine used in almost all automobiles today. It has got the name as the working consists of 4 strokes namely Intake, Compression, Power and Exhaust.

In Intake Stroke compressed air and gasoline are in taken (only compressed air in case of diesel engines). In Compression stroke, this mixture is compressed and during compression spark plug is ignited (in case of diesel engines, diesel is sucked in and the high pressure is enough for auto ignition). In Power stroke, due to the blast power is produced and the gases expand. In the Exhaust stroke, the waste gases are sent out.

Generally the efficiency of a gasoline engine is around 35-40%. One of the easy ways of increasing the efficiency is by increasing the air flow. All of us know about the candle light experiment. Burn a candle and place it inside a close container. It will blow off when there is no oxygen. Imagine a bigger container. It will glow for some more time. Similarly if there is no air, then some fuel will be left unburned. So, by increasing the air in taken or by increasing the air pressure, we can increase the efficiency.

Schematic Diagram of a Turbocharger

The technique is simple. Keep a turbine in the exhaust of the engine. So the exhaust gases hit the turbine. The turbine shaft is connected to the intake compressor shaft. So the exhaust air forces the compressor to spin faster and thus the pressure of the intake air is increased. Thus the power produced is increased. The increase in efficiency depends on lot of factors like size of turbochargers, though an increase of 30-40% can be expected.

Let us see another interesting topic next time.


Reference: 
Turbochargers - How Stuff Works
Forced Air and the Future - The Auto Rules

Happy Reading!!!

Things that crossed my way!

Hi Guys,

It’s nearly 10 days since I wrote my last post. I was busy with my internal exams and also was engrossed in World cup cricket matches.

Cricket Celebrations

It was an unforgettable Saturday. A day that will be etched in all our minds. A day when the dream came true. The celebrations following the win were also memorable. There were crackers and fireworks all around. The newspapers celebrated the victory with so much of enthusiasm. It was then that all the state governments started to announce crores of prize money to the cricketers. The question that came to my mind was ‘Do the cricketers really need it?’ They are already earning crores in IPL and moreover the money they earn in ads is unbelievable. Comparing with them, the prize money is so small. But the money belongs to the people. Think, how much can be done with this money. So, what I feel the money is going to be wasted ultimately.

Elections – A week ahead

We are getting our state assembly elections in a week and I’m really delighted since it is going to be the first time, I’m going to take part in one of the country’s pride – Democracy. It is also really heartening to see that all my classmates are looking forward to cast their vote. So, people who say that young people don’t care about the elections, please change your mind.

Election Commission has been really strict in following the rules and as a result, we don’t even feel like we are nearing elections. There are no banners, no pamphlets, no flags, etc. It is really incredible.

The Shining – Stanley Kubrick (1980)

Two days ago, I watched this horrific thriller movie. Based on Stephen King’s novel named the same, this movie deals with a family who stays in a hotel at Denver during the winter season as caretaker. Everything goes fine, before Jack Nicholson turns crazy and starts to hunt his wife Shelley Duvall and little son Danny. Do they survive it?

The poster says it all

The background music is really scary and it is the biggest plus of the movie. Even you get scared for ordinary scenes. The acting of the trio is also remarkable. Particularly the little boy captures the viewer's heart. To be true, this was the first time I have been so haunted seeing a horror movie.

Manufacturing of Pencils

I came across this wonderful video in youtube. It is a video if Staedtler’s pencil manufacturing. A pencil is simple in its appearance. See this video to know the things behind the manufacturing of pencil.

That’s it for now!!!

Happy Reading!!!

Automobile Videos - 3

Hi Guys,

(preceded by Automobile Videos -2)

This week was a wonderful one for me. I was having nearly no academic works and was hence able to concentrate on lot of other things. It was a great learning week for me. Can’t believe it is Saturday already.

Correction

In the Automobile Videos -2 post, I mentioned that steering work by using the rack and pinion arrangement. It is one of the types of steering. There are many type of steering. Another major type of steering is ‘Recirculating ball steering’. Click the below links to know more about Steering.

http://auto.howstuffworks.com/steering.htm

http://www.indiacar.com/infobank/skg_articles/sept05/fundamentals.asp

Turbochargers

Turbochargers are devices used to upsurge the efficiency of an automobile engine. To increase the efficiency, the amount of fuel burnt or the amount of air in taken must be increased. Enlarging the cylinder size is one option, but it is not feasible in most of the cases. So we use turbochargers. They are kept in the exhaust manifold of the engine. Turbochargers use a turbine, which is spun by the exhaust gases. So the turbine generates wind and is supplied to the cylinders. This is the principle of turbocharger.

It is particularly very useful in case of hilly regions as the amount of oxygen reduces with altitude (so does the pressure). At these places, the turbochargers make sure that the engine functions properly. The video will explain the things more clearly.

Mercedes Benz 4matic Technology

When you think of Mercedes Benz, you will be just awestruck. Generally, the power generated in an engine will be transmitted to the rear axle (back wheels) through the differential. Certain vehicles transmit a little amount of power to the front axle (using another differential known as auxiliary differential).

Mercedes Benz has introduced a concept called 4matic technology. They use an electronic chip in the differential and this pre-programmed chip governs the power transmitted to all the four wheels. Generally 60% power is transmitted to the rear axle and the remaining 40% is transmitted to the front axle. If the road is bumpy at a certain place, then the chip locks the particular wheel alone. This means there will be a lot of safety to the passengers. Watch the video and you will be mesmerized.

With this I finish the Automobile Videos sequence temporarily.

Happy Reading!!!

Automobile Videos - 2

Hi Guys,

This is the continuation of Automobile Videos -1 post.

Working of Catalytic Converter

First, what is catalytic converter? Catalytic converter is a device kept in the exhaust pipe of Automobiles. Basically automobile exhaust consists of gases like Sulphur dioxide, carbon monoxide and oxides of nitrogen along with some unburned fuel. If these gases are let out into the atmosphere, pollution will increase enormously. So, we use catalytic converters to control the emission. They basically consist of minute matrix shaped structures made of platinum and rhodium or platinum and palladium. They act as catalysts and convert the harmful gases into nearly harmless gases. One drawback is that they work only at high temperatures and hence, they are activated only after traveling for 6 miles.

Check the video to know more detailed information and a superb animation of the process.

Working of Power Steering

Rack and Pinion

In the earlier days, it used to be hard for the drivers to steer a vehicle. Even for a small turn, they needed to apply a lot of effort. But, driving has become very comfortable after the advent to power steering. Steering is generally based on a rack and pinion arrangement. Whenever the steering wheel is turned the pinion moves on the rack and the wheel is turned. The difference between a normal steering and a power steering is that, in normal steering driver has to apply all the force required to turn, but in a power steering he is helped by the hydraulic force.  Refer the video for getting a clear cut view. A car racer explains the principle of power steering.

(To be continued…)

Happy Reading!!!

Automobile Videos - 1

Hi Guys,

I was just seeing some videos about various technologies used in automobiles. Started with things in my syllabus and later went into things. They were just wonderful. I will post the videos in the next couple of posts along with explanations.

Note: The 1^st video is more technical and the 2^nd video is more general. But both the videos are suitable for all.

How Differential Works?

First, differential is a device used in automobiles to control the speed of the rear wheels particularly during turning. Power generated in the engine is transmitted through clutch, gearbox and propeller shaft. From propeller shaft, the differential divides the power equally to both the wheels. When the vehicle turns left, the left wheel should turn a shorter distance and right wheel should cover a larger distance. Differential takes care of it.

The concept is difficult to understand. Chevrolet has released a wonderful video explaining the working of differential using steel bars. This 1930 video is still used to explain the working of differential. See the video and you will understand.

Aerodynamics of Aeroplanes, Cars

I’ve heard of Aerodynamic effects on automobiles, but never in such a way. The effect of Aerodynamics is same, but the way it is used in Aeroplanes, cars and racing cars are different. In Aeroplanes, it is used for the flight. In cars, Aerodynamics needs to be controlled to keep the car on land and in racing cars, to speed the cars. Can’t explain the things in words, the 10 minute video from Audi will explain better. If you play car racing games, you will know the use of Spoilers.

(To be continued…)

Happy Reading!!!

Interesting Automobile Videos from YouTube

Hi Guys,

In this post, I'll be attaching some interesting videos related with automobile.
I came across these videos in YouTube last week.

Henry Ford's Assembly Line concept

How an Engine Works- A video from How Stuff Works

Ford Engine's Animation

How clutches work- A video from Howstuff works

Manufacturing of a Marine Engine at Caterpillar

Happy Viewing!!!