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August 31, 2019
A new nuclear power station in the south-west of the UK will be the most expensive object on Earth. That's the claim about the proposed plant at Hinkley Point in Somerset - but has anything else ever cost so much to build?
"Hinkley is set to be the most expensive object on Earth… best guesses say Hinkley could pass £24bn ($35bn)," said the environmental charity Greenpeace last month as it launched a petition against the project.
This figure includes an estimate for paying interest on borrowed money, but the financing arrangements for Hinkley C are so opaque that it is impossible to calculate exactly what the final cost will be.
Even if you stick with the expense of construction alone, though, the price is still high - the main contractor, EDF, puts it at £18bn ($26bn).For that sum you could build a small forest of Burj Khalifas - the world's tallest building, in Dubai, cost a piffling £1bn ($1.5bn). You could also knock up more than 70 miles of particle accelerator. The 17-mile-long Large Hadron Collider, built under the border between France and Switzerland to unlock the secrets of the universe, cost a mere £4bn ($5.8bn).
The most expensive bridge ever constructed is the eastern replacement span of the Oakland Bay Bridge in San Francisco, designed to withstand the strongest earthquake seismologists would expect within the next 1,500 years. That cost about £4.5bn ($6.5bn).So why is Hinkley C so expensive?
"Nuclear power plants are the most complicated piece of equipment we make," says Steve Thomas, emeritus professor of energy policy at Greenwich University.
"Cost of nuclear power plants has tended to go up throughout history as accidents happen and we design measures to deal with the risk."
In comparison, the UK's newest nuclear power station, Sizewell B, which was completed in 1995, only cost £2.3bn ($3.4bn), or £4.1bn ($6bn) at today's prices.
No nuclear power plants have been completed in Europe this century - those that have been built in recent years are in countries such as China or India, and Thomas believes figures for these, where they exist, are not reliable.
So what about historic buildings - could the Great Pyramid of Giza put Hinkley C in the shade?Working out the cost of something built more than 4,500 years ago presents numerous challenges, but in 2012 the Turner Construction Company estimated it could build the pyramid for between £750m ($1.1bn) and £900m ($1.3bn).
That includes about £500m ($730m) for stone and £40m ($58m) for 12 cranes. However, it projected that a mere 600 staff would be necessary - it took 20,000 people to build the original pyramid at a time when the only cranes in sight were the winged, feathery type.
And the cost to Pharaoh Khufu? For two decades, workers are believed to have laboured on the pyramid for four months a year, during the annual Nile flood when the fields they normally tended were submerged. That amounts to 48.4 million days of labour. A further 4,000 people are thought to have worked year-round, giving a total figure of 77.6 million days' labour. Using the current Egyptian minimum wage of £3.93 ($5.73) a day, that gives a labour cost of £305m ($445m).
Using modern labour rates is not as strange as it might seem. A contemporaneous inscription reveals labourers received 10 loaves of bread and a jug of beer per day. Archaeological evidence suggests the pyramid builders also received meat and fish, and in modern Egypt 10 loaves, a can of Coca-Cola and a portion of beef or fish costs about £4 ($5.80).
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More stories from More or Less And the Pharaoh didn't have to pay for raw materials.
"The king owned all the stone in the quarries," says Joyce Tyldesley, lecturer in Egyptology at Manchester University. "He couldn't sell this - nobody would have a use for it. His palaces and temples were made of mud brick and so were peoples' houses. Nobody would have the resources to buy it. It's a free resource."
She thinks the labour was effectively free too. Workers were paid with food that the pharaoh had gathered in as taxation.
"If he doesn't spend it on his workforce it won't last, he'll have to redistribute it another way," she says. "I would argue the entire pyramid-building experience was free."
In any case, a £500m stone bill plus £305m in wages are nowhere near Hinkley C.The Great Wall of China was an even bigger project than the pyramid. At 5,500 miles long, its mass is almost certainly greater. But it is actually a large number of walls, pieced together over two millennia, stretching the definition of "object".
Back in the modern era, neither Heathrow Terminal 2 (£2.3bn; $3.4bn) nor the new London railway Crossrail (£14.8bn; $21.6bn) can compete with Hinkley.
One current project, at first glance, does appear to be in the same ballpark as the power station. The royal family of Saudi Arabia is refurbishing the Grand Mosque in Mecca at a reported cost of about £16bn ($23bn). But this includes a new road and train line, among other things, so, once again, it stretches the definition of "object".Another contender is Hong Kong International Airport, built in 1998 on an artificial island at a cost of £13.7bn ($20bn) - equivalent to £20.1bn ($29bn) at today's prices. That just pips EDF's estimate for the cost of Hinkley C (though remember, we are putting to one side the cost of financing the deal).
But these are all exceeded by the $54bn (£37bn) Gorgon liquefied natural gas plant built by Chevron in Australia. Built on Barrow Island off the country's north-west coast to process a huge off-shore gas field, it began production in March.
Even that will probably be overtaken one day, though. "We're just building two reactors at Hinkley. Turkey has a deal for four reactors, South Africa is about to launch a tender for six reactors," says Steve Thomas. "When you get round to a six-reactor order it's going to cost three times as much as Hinkley."
And whatever the most expensive object on Earth is, up in the sky is something that eclipses all of these things.
The International Space Station. Price tag: 100bn euros (£77.6bn, or $110bn).
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August 31, 2019
Many graduates harbour management aspirations. To impress business employers and climb the career ladder, you'll need to brush up on the following management skills


Interpersonal skills

Management jobs are all about people and being able to build successful relationships is integral. If you want to lead a team you'll first need to earn the respect of your colleagues and to do this you need to know how to effectively deal with other people.
Setting time aside to get to know your team members on both a personal and professional level, perhaps through social activities or team-building training, while still maintaining professional boundaries, will go a long way to earning their respect.
You need to demonstrate your managerial qualities and authority while maintaining the ability to play your part as a member of a team.

Communication and motivation

Effective leaders must master all forms of communication including written, verbal and listening skills. As a team manager you're the line of communication between frontline staff and senior management, so you'll need to be able to communicate with a variety of people from entry-level employees to heads of departments and CEOs in a number of different ways such as via email and social media, over the phone and in presentations, meetings and one-to-ones.
As a leader you'll need to establish a trusting relationship with your employees so they feel comfortable sharing information with you and vice versa. To ensure that lines of communication remain open you'll need to make yourself readily available and accessible to your employees to discuss any issues or concerns that arise. Putting in place an open door policy or weekly or monthly team meetings should facilitate this. When communicating let your staff know that they matter by keeping eye contact, smiling and listening attentively.
Projecting an open, positive attitude at work goes a long way to creating a happy and healthy work environment. Don't shut yourself off or put yourself on a pedestal. Simple things such as active encouragement, recognising achievements and taking an interest in the lives of your employees boosts morale and ensures that staff feel valued by the company. If people are a product of their environment, a positive workplace creates happy, motivated employees.

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August 31, 2019 1

Engineers are often math enthusiasts who got bored with the abstract. Even though number crunching is significant to engineers’ work, math is no more than a convenient means to arrive at a physical end. The type of math an engineer uses will depend on the type of engineer he is and the type of project in which he's involved.


Basic Arithmetic
All math is based on the idea that 1 plus 1 equals 2, and 1 minus 1 equals 0. Multiplication and division –2 times 2 and 4 divided by 2 – are variations used to avoid multiple iterations of either subtraction or addition. One example of an engineer's use of basic arithmetic is the civil engineer's calculations for describing water flow across an open basin. The flow is reckoned in cubic feet per second, or Q, where Q equals the runoff coefficient times the intensity of the rain for a specified period, times the area of the basin. If the runoff coefficient is 2, the intensity, in inches of rain, is 4 and the basin – a specified area of land – is 1/2 acre, the engineer's formula resembles this: (2x4)/(.5x43,560), or 8/21,780. The result, 0.0003673, is the volume of water, in cubic feet per second, flowing across the land.
Algebra and Geometry
When several of the factors of a problem are known and one or more are unknown, engineers use algebra, including differential equations in cases when there are several unknowns. Because engineers work to arrive at a solution to a physical problem, geometry – with its planes, circles and angles – determines such diverse things as the torque used to turn a wheel, and reduces the design of a roadway's curve to an accurate engineering or construction drawing.

Trigonometry
Trigonometry is the science of measuring triangles. Engineers may use plane trigonometry to determine the size of an irregularly shaped parcel of land. It may also be used or to determine the height of an object based solely on the distance to the object and the angle, up or down, from the observer. Spherical trigonometry is used by naval engineers in ship design and by mechanical engineers working on such arcane projects as the design of mechanical hand for an underwater robot.
Statistics
We all love statistics. They tell us where we stand in the world, among our peers and even in our family. They tell us who's winning. The engineer uses them for the same reasons – by statistical analysis of the design, the engineer can tell what percentage of a design will need armor or reinforcement or where any likely failures will occur. For the civil engineer, statistics appear as the concentration of rainfall, wind loads and bridge design. In many locations, engineers designing drainage systems must design for a 50- or 100-year storm in their calculations, a significant change from the normal rain concentration.
Calculus
Calculus is used by engineers to determine rates of change or rates by which factors, such as acceleration or weight, change. It might tell NASA scientists at what point the change in a satellite's orbit will cause the satellite to strike an object in space. A more mundane task for calculus might be determining how large a box must be to accommodate a specific number of things. An engineer who designs packaging, for example, might know that a product of a certain weight must be packaged in groups of no more than 10 because of their weight. Using calculus, he can calculate both the optimum number of objects per box, plus the optimum size of the box.


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August 30, 2019
Three fundamental things can happen: a bad fuel mix, lack of compression or lack of spark. Beyond that, thousands of minor things can create problems, but these are the "big three." Based on the simple engine we have been discussing, here is a quick rundown on how these problems affect your engine:

Bad fuel mix - A bad fuel mix can occur in several ways:
· You are out of gas, so the engine is getting air but no fuel.
· The air intake might be clogged, so there is fuel but not enough air.
· The fuel system might be supplying too much or too little fuel to the mix, meaning that combustion does not occur properly.
· There might be an impurity in the fuel (like water in your gas tank) that makes the fuel not burn.
Lack of compression - If the charge of air and fuel cannot be compressed properly, the combustion process will not work like it should. Lack of compression might occur for these reasons:
· Your piston rings are worn (allowing air/fuel to leak past the piston during compression).
· The intake or exhaust valves are not sealing properly, again allowing a leak during compression.
·  There is a hole in the cylinder.
The most common "hole" in a cylinder occurs where the top of the cylinder (holding the valves and spark plug and also known as the cylinder head) attaches to the cylinder itself. Generally, the cylinder and the cylinder head bolt together with a thin gasket pressed between them to ensure a good seal. If the gasket breaks down, small holes develop between the cylinder and the cylinder head, and these holes cause leaks.
Lack of spark - The spark might be nonexistent or weak for a number of reasons:
· If your spark plug or the wire leading to it is worn out, the spark will be weak.
· If the wire is cut or missing, or if the system that sends a spark down the wire is not working properly, there will be no spark.
· If the spark occurs either too early or too late in the cycle (i.e. if the ignition timing is off), the fuel will not ignite at the right time, and this can cause all sorts of problems.

Many other things can go wrong. For example:
·If the battery is dead, you cannot turn over the engine to start it.
·If the bearings that allow the crankshaft to turn freely are worn out, the crankshaft cannot turn so the engine cannot run.
·If the valves do not open and close at the right time or at all, air cannot get in and exhaust cannot get out, so the engine cannot run.
·If someone sticks a potato up your tailpipe, exhaust cannot exit the cylinder so the engine will not run.
·If you run out of oil, the piston cannot move up and down freely in the cylinder, and the engine will seize.
In a properly running engine, all of these factors are within tolerance.
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August 29, 2019
Twenty thousand years ago, if you'd needed to dig a hole in rough ground, chances are you would have found yourself swinging a sharpened deer antler over your head. Modern pickaxes are based on pretty much the same idea. The long wooden handle and metal blade act like levers to magnify the force you generate with your back muscles and arms. It's simple technology, but it's very effective.
Today, if you want to dig a hole in a hurry and there's a thick lump of concrete or asphalt in your way, you're most likely to use a jackhammer, also known as a pneumatic (air-powered) drill, rock drill, or pavement breaker. A strong and skilled road worker can swing a pickaxe 10 times a minute or more, but a jackhammer can pound the ground 150 times faster—that's 1500 times a minute! Pretty amazing, but how exactly does it work?

The first time you saw someone digging a hole in the road with a tool like this, you probably thought the equipment was electric or powered by a diesel engine, right? In fact, the only energy involved in making a jackhammer pound up and down is supplied from an air hose. The hose, which has to be made of especially thick plastic, carries high-pressure air (typically 10 times higher pressure than the air around us) from a separate air-compressor unit powered by a diesel engine.
The air compressor is a bit like a giant bicycle pump that never stops blowing air. When the worker presses down on the handle, air pumps from the compressor into the jackhammer through a valve on one side. Inside the hammer, there's a circuit of air tubes, a heavy piledriver, and a drill bit at the bottom. First, the high-pressure air flows one way round the circuit, forcing the piledriver down so it pounds into the drill bit, smashing it into the ground. A valve inside the tube network then flips over, causing the air to circulate in the opposite direction. Now the piledriver moves back upward, so the drill bit relaxes from the ground. A short time later, the valve flips over again and the whole process repeats. The upshot is that the piledriver smashes down on the drill bit over 25 times each second, so the drill pounds up and down on the ground around 1500 times a minute.
Jackhammers, and the air compressors that power them come in all different shapes and sizes. The drill bits on the end are interchangeable too. There are wide chisels, narrow chisels, and tools called moil points for fine work. A skilled drill operator can loosen chunks of the road in just 10-20 seconds, making light work of what our ancestors—with their antler picks—would have found truly backbreaking work!

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August 28, 2019
A turbocharger or turbo is a forced induction device used to allow more power to be produced for an engine of a given size. A turbocharged engine can be more powerful and efficient than a naturally aspirated engine because the turbine forces more intake air, proportionately more fuel, into the combustion chamber than if atmospheric pressure alone is used. Turbo are commonly used on truck, car, train, and construction equipment engines. Turbo are popularly used with Otto cycle and Diesel cycle internal combustion engines.
There are two ways of increasing the power of an engine. One of them would be to make the fuel-air mixture richer by adding more fuel. This will increase the power but at the cost of fuel efficiency and increase in pollution levels… prohibitive! The other would be to somehow increase the volume of air entering into the cylinder and increasing the fuel intake proportionately, increasing power and fuel efficiency without hurting the environment or efficiency. This is exactly what Turbochargers do, increasing the volumetric efficiency of an engine.
In a naturally aspirated engine, the downward stroke of the piston creates an area of low pressure in order to draw more air into the cylinder through the intake valves.  Now because of the pressure in the cylinder cannot go below 0 (zero) psi (vacuum) and relatively constant atmospheric pressure (about 15 psi) there will be a limit to the pressure difference across the intake valves and hence the amount of air entering the combustion chamber or the cylinder. The ability to fill the cylinder with air is its volumetric efficiency. Now if we can increase the pressure difference across the intake valves by some way we can make more air enter into the cylinder and hence increasing the volumetric efficiency of the engine.
It increases the pressure at the point where air is entering the cylinder, thereby increasing the pressure difference across the intake valves and thus more air enters into the combustion chamber. The additional air makes it possible to add more fuel, increasing the power and torque output of the engine, particularly at higher engine speeds.
Turbochargers were originally known as Turbo superchargers when all forced induction devices were classified as superchargers; nowadays the term "supercharger" is usually applied to only mechanically-driven forced induction devices. The key difference between a turbocharger and a conventional supercharger is that the latter is mechanically driven from the engine, often from a belt connected to the crankshaft, whereas a turbocharger is driven by the engine's exhaust gas turbine. Compared to a mechanically-driven supercharger, turbochargers tend to be more efficient but less responsive.
HISTORICAL PERSPECTIVE
The turbocharger was invented by Swiss engineer Alfred Büchi. His patent for a turbocharger was applied for use in 1905. Diesel ships and locomotives with turbochargers began appearing in the 1920s.
AVIATION:
During the First World War French engineer AugusteRateau fitted turbochargers to Renault engines powering various French fighters with some success. In1918, General Electric engineer Sanford Moss attached a turbo to a V12 Liberty aircraft engine. The engine was tested at Pikes Peak in Colorado at 4,300 m to demonstrate that it could eliminate the power losses usually experienced in internal combustion engines as a result of reduced air pressure and density at high altitude.
Turbochargers were first used in production aircraft engines in the 1920s, although they were less common than engine-driven centrifugal superchargers. The primary purpose behind most aircraft-based applications was to increase the altitude at which the airplane could fly, by compensating for the lower atmospheric pressure present at high altitude.
PRODUCTION AUTOMOBILES:
The first turbocharged diesel truck was produced by Schweizer Maschinenfabrik Saurer (Swiss Machine Works Saurer) in 1938 .The first production turbocharged automobile engines came from General Motors in 1962. At the Paris auto show in1974, during the height of the oil crisis, Porsche introduced the 911 Turbo – the world’s first production sports car with an exhaust turbocharger and pressure regulator. This was made possible by the introduction of a waste gate to direct excess exhaust gasses away from the exhaust turbine. The world's first production turbo diesel automobiles were the Garrett-turbocharged Mercedes 300SD and the Peugeot 604, both introduced in 1978. Today, most automotive diesels are turbocharged.
1962 Oldsmobile Cutlass Jet fire
1962 Chevrolet Corvair Monza Spyder
1973 BMW 2002 Turbo
1974 Porsche 911 Turbo
1978 Saab 99
1978 Peugeot 604 turbo diesel
1978 Mercedes-Benz 300SD turbo diesel (United States/Canada)
1979 Alfa Romeo Alfetta GTV 2000 Turbodelta
1980 Mitsubishi Lancer GT Turbo
1980 Pontiac Firebird
1980 Renault 5 Turbo
1981 Volvo 240-series Turbo
OPERATING PRINCIPLE
A turbocharger is a small radial fan pump driven by the energy of the exhaust gases of an engine. A turbocharger consists of a turbine and a compressor on a shared shaft. The turbine converts exhaust heat to rotational force, which is in turn used to drive the compressor. The compressor draws in ambient air and pumps it in to the intake manifold at increased pressure resulting in a greater mass of air entering the cylinders on each intake stroke.
The objective of a turbocharger is the same as a supercharger; to improve the engine's volumetric efficiency by solving one of its cardinal limitations. A naturally aspirated automobile engine uses only the downward stroke of a piston to create an area of low pressure in order to draw air into the cylinder through the intake valves. Because the pressure in the atmosphere is no more than 1 atm (approximately 14.7 psi), there ultimately will be a limit to the pressure difference across the intake valves and thus the amount of airflow entering the combustion chamber.
Because the turbocharger increases the pressure at the point where air is entering the cylinder, a greater mass of air (oxygen) will be forced in as the inlet manifold pressure increases. The additional air flow makes it possible to maintain the combustion chamber pressure and fuel/air load even at high engine revolution speeds, increasing the power and torque output of the engine. Because the pressure in the cylinder must not go too high to avoid detonation and physical damage, the intake pressure must be controlled by venting excess gas. The control function is performed by a waste gate, which routes some of the exhaust flow away from the turbine. This regulates air pressure in the intake manifold.
COMPONENTS OF A TURBOCHARGER
The turbocharger has four main components. The turbine (almost always a radial turbine) and impeller/compressor wheels are each contained within their own folded conical housing on opposite sides of the third component, the center housing/hub rotating assembly. The housings fitted around the compressor impeller and turbine collect and direct the gas flow through the wheels as they spin. The size and shape can dictate some performance characteristics of the overall turbocharger. The turbine and impeller wheel sizes dictate the amount of air or exhaust that can be flowed through the system, and the relative efficiency at which they operate. Generally, the larger the turbine wheel and compressor wheel, the larger the flow capacity. The center hub rotating assembly houses the shaft which connects the compressor impeller and turbine. It also must contain a bearing system to suspend the shaft, allowing it to rotate at very high speed with minimal friction. Waste gates for the exhaust flow.
TURBINE WHEEL:
The Turbine Wheel is housed in the turbine casing and is connected to a shaft that in turn rotates the compressor wheel.
COMPRESSOR WHEEL (IMPELLER)
Compressor impellers are produced using a variant of the aluminum investment casting process. A rubber former is made to replicate the impeller around which a casting mould is created. The rubber former can then be extracted from the mould into which the metal is poured. Accurate blade sections and profiles are important in achieving compressor performance. Back face profile machining optimizes impeller stress conditions. Boring to tight tolerance and burnishing assist balancing and fatigue resistance. The impeller is located on the shaft assembly using a threaded nut.
WASTE GATES:
On the exhaust side, a Waste gate provides us a means to control the boost pressure of the engine. Some commercial diesel applications do not use a Waste gate at all. This type of system is called a free-floating turbocharger. However, the vast majority of gasoline performance applications require Waste gates. Waste gates provide a means to bypass exhaust flow from the turbine wheel. Bypassing this energy (e.g. exhaust flow) reduces the power driving the turbine wheel to match the power required for a given boost level.


ADVANTAGES
1. More specific power over naturally aspirated engine. This means a turbocharged engine can achieve more power from same engine volume.
2. Better thermal efficiency over both naturally aspirated and supercharged engine when under full load (i.e. on boost). This is because the excess exhaust heat and pressure, which would normally be wasted, contributes some of the work required to compress the air.
3. Weight/Packaging. Smaller and lighter than alternative forced induction systems and may be more easily fitted in an engine bay.
4. Fuel Economy. Although adding a turbocharger itself does not save fuel, it will allow a vehicle to use a smaller engine while achieving power levels of a much larger engine, while attaining near normal fuel economy while off boost/cruising. This is because without boost, less fuel is used to create a proper air/fuel ratio.
DISADVANTAGES
1. Lack of responsiveness if an incorrectly sized turbocharger is used. If a turbocharger that is too large is used it reduces throttle response as it builds up boost slowly otherwise known as "lag". However, doing this may result in more peak power.
2. Boost threshold- A turbocharger starts producing boost only above a certain rpm due to a lack of exhaust gas volume to overcome inertia of rest of the turbo propeller. This results in a rapid and nonlinear rise in torque, and will reduce the usable power band of the engine. The sudden surge of power could overwhelm the tires and result in loss of grip, which could lead to under steer/over steer, depending on the drive train and suspension setup of the vehicle. Lag can be disadvantageous in racing, if throttle is applied in a turn, power may unexpectedly increase when the turbo spools up, which can cause excessive wheel spin.
3. Cost- Turbocharger parts are costly to add to naturally aspirated engines. Heavily modifying OEM turbocharger systems also require extensive upgrades that in most cases requires most (if not all) of the original components to be replaced.
4. Complexity- Further to cost, turbochargers require numerous additional systems if they are not to damage an engine. Even an engine under only light boost requires a system for properly routing (and sometimes cooling) the lubricating oil, turbo-specific exhaust manifold, application specific downpipe, boosts regulation. In addition inter -cooled turbo engines require additional plumbing, while highly tuned turbocharged engines will require extensive upgrades to their lubrication, cooling, and breathing systems; while reinforcing internal engine and transmission parts.
TURBO LAG AND BOOST
The time required to bring the turbo up to a speed where it can function effectively is called turbo lag. This is noticed as a hesitation in throttle response when coming off idle. This is symptomatic of the time taken for the exhaust system driving the turbine to come to high pressure and for the turbine rotor to overcome its rotational inertia and reach the speed necessary to supply boost pressure. The directly-driven compressor in a supercharger does not suffer from this problem. Conversely on light loads or at low RPM a turbocharger supplies less boost and the engine acts like a naturally aspirated engine. Turbochargers start producing boost only above a certain exhaust mass flow rate (depending on the size of the turbo). Without an appropriate exhaust gas flow, they logically cannot force air into the engine. The point at full throttle in which the mass flow in the exhaust is strong enough to force air into the engine is known as the boost threshold rpm. Engineers have, in some cases, been able to reduce the boost threshold rpm to idle speed to allow for instant response. Both Lag and Threshold characteristics can be acquired through the use of a compressor map and a mathematical equation.
APPLICATIONSGasoline-powered cars
Today, turbocharging is commonly used by many manufacturers of both diesel and gasoline-powered cars. Turbo charging can be used to increase power output for a given capacity or to increase fuel efficiency by allowing a smaller displacement engine to be used. Low pressure turbocharging is the optimum when driving in the city, whereas high pressure turbocharging is more for racing and driving on highways/motorways/freeways.
Diesel-powered cars
Today, many automotive diesels are turbocharged, since the use of turbocharging improved efficiency, driveability and performance of diesel engines, greatly increasing their popularity.
Motorcycles
The first example of a turbocharged bike is the 1978 Kawasaki Z1R TC. Several Japanese companies produced turbocharged high performance motorcycles in the early 1980s. Since then, few turbocharged motorcycles have been produced.
Trucks
The first turbocharged diesel truck was produced by Schweizer Maschinenfabrik Saurer (Swiss Machine Works Saurer) in 1938.
Aircraft
A natural use of the turbocharger is with aircraft engines. As an aircraft climbs to higher altitudes the pressure of the surrounding air quickly falls off. At 5,486 m (18,000 ft), the air is at half the pressure of sea level and the airframe experiences only half the aerodynamic drag. However, since the charge in the cylinders is being pushed in by this air pressure, it means that the engine will normally produce only half-power at full throttle at this altitude. Pilots would like to take advantage of the low drag at high altitudes in order to go faster, but a naturally aspirated engine will not produce enough power at the same altitude to do so.
Here the main aim is to effectively utilize the non renewable energy such as petrol and diesel. Complete combustion of the fuels can be achieved. Power output can be increased. Wind energy can be used for air compression. We conclude that the power as well as the efficiency is increasing 10 to 15 % and pollution can also decrease. From the observation we can conclude that when the full throttle valve is open at that time the engine speed is 4000 rpm and by this the turbocharger generate 1.60 bar pressurized air. Generally the naturally aspirated engine takes atmospheric pressurized air to the carburetor for air fuel mixture but we can add the high density air for the combustion so as the result the power and the complete combustion take place so efficiency is increasing.
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