Petrol vs diesel vs CNG vs LPG.

Since the start of 2010, petrol prices have been revised 11 times going up from Rs 44.7 per litre in January 2010 to Rs 63.66 today, a whopping 42% rise. Diesel prices have suffered a change 8 times in the same duration, as prices have risen at a more humane 25%. While this widening gap between the prices of the two fuels has triggered a shift in the buying pattern of cars, a more informed and analysed approach is needed to determine which is an outright better option in the medium to long term. At the same time should one look at CNG and LPG as well?

Traditionally berated for being dirty and noisy, diesel has clearly emerged as the fuel of choice for the Indian market. Wherever a car is available in diesel and petrol, it is the former that outsells and the margin is only increasing. Even the Rs 80,000-100,000 higher price tag of a diesel car is no longer a deterrent as consumers reckon it ends up to be a better deal in the end.
But does it really make all that sense for everybody to ditch petrol and settle for diesel? Or should one also consider other options like LPG and CNG as well?
Diesel: fun, Petrol: power
Technological advancement has ensured that diesel today is a clean burning fuel that emits 15% lower carbon dioxide than petrol. Clearly, associating it with the black noxious fumes being exhumed by yesteryear’s trucks on state highways, would be a complete misnomer.
A diesel engine has a much higher compression ratio as it relies completely on it to combust the fuel unlike petrol engines which require external ignition by way of spark plugs. Because of this basic difference, a diesel engine is heavier by nature designed to generate compression ratios between 12:1 and 25:1. Petrol engines on the other need compression ratios only between 8:1 and 12:1.
For the lay consumer behind the wheel though, the difference between a diesel and petrol car is in the two’s distinct driveability. If a similar sized diesel and petrol engine is compared, like in the case of Ritz which is powered by a 1.2 litre K series petrol engine and a 1.3 litre multijet DDiS diesel engine, the former develops 85 PS power and 113 Nm torque. The diesel engine on the other hands belts out a lower 75 PS power but a much higher 190 Nm torque.
More power means the petrol Ritz is capable of doing much higher speeds while its diesel counterpart will start huffing and puffing at three digit speeds. The petrol variant however boasts of lower torque figures, once again a fall out of lower compression ratio. Torque is the force needed to rotate a wheel and the diesel variant’s higher torque ensures it is faster off the block and commands better acceleration. In city traffic therefore the diesel is more fun to drive as also in cases when a quick overtaking manoeuvre is necessitated on the highway.
Petrol
Pros : Lower cost of car, refinement, power
Cons : Higher cost of fuel, likely to get even higher
Diesel
Pros : Mileage, lower cost of ownership, peppier drive
Cons : Expensive technology, coarse and noisier, lower top end power.
The CNG-LPG factor
Consumers in some metros and other big cities today have the choice of CNG and LPG as well, and these are being offered by some manufacturers like Maruti, Hyundai, Tata and Chevrolet as factory fitment as well. They also have the advantage of being fitted from the market place on any car, a choice that diesel certainly lacks.
Due to the restricted availability of compressed natural gas, its growth is not talked about in the same vein as diesel. But wherever CNG is available, like Delhi NCR, parts of Gujarat and some other towns in UP, Haryana and Rajasthan, it has come up as a very strong competitor.
Globally as well, CNG is increasingly becoming a favoured mode of fuel. Outside the hybrid technologies, it is the cleanest fuel available with CO2 emissions, 20% lower than a conventional gasoline vehicle. It is also the cheapest at under Rs 30 per kilogram.
What also augers well for CNG is that there is no lack of availability of the fuel in India. India has the 7th largest reserves of CNG in the world though most of it is untapped and needs investment. It is without doubt the fuel of the future and once it is available in more abundance, its price, which is already lower than the others, would come down further.
One big factor against use of CNG as an automotive fuel used to be the lack of safety (cases of fire are still reported) and power loss that drastically reduced the pleasure of driving especially when the air conditioner is switched on. Further, in the case of small cars, the 20kg cylinder almost always takes away all of the boot space, a not too favourable prospect.
The first part of the problem however, has been addressed to some extent, with carmakers like Maruti introducing gas port injection technology. Since the modifications that include dual inter dependent ECU mapping, is done at the factory level, the cars are well tested for safety and also carry the manufacturer’s warranty. In the erstwhile CNG technology, the kits were retrofitted that automatically led to the annulment of the manufacturer’s 2-3 year warranty.
The newer technology has also reduced the power loss associated with CNG and these cars now have pick up and drive similar to that of a petrol car. Almost.
Automotive Liquified petroleum gas on the other hand is well past its sell by date and is unlikely to find much favour in the market in the years to come. It is not hampered by availability issues as much as CNG, but its price mirrors that of domestic LPG, a heavily subsidised fuel, and has risen the most in the last 20 years.
CNG
Pros : Lower cost, fuel of the future, lower emissions, very popular worldwide too
Cons : Boot space is compromised, lack of availability, serpentine queus.
LPG
Pros : Lower cost compared to petrol, better distribution than CNG, boot space only partially compromised
Cons : No longer a very cheap fuel
Who is the best of them all?
It takes a little bit of science and a lot of hypothesis to decipher, which fuel option would be the best in the medium term (say 3 years) to long term (5-8 years). Since 1989, petrol prices have been revised on 70 occasions, of which 54 times prices have gone up and 16 times it has come down. Diesel prices have been revised 73 times with an increase happening on 50 occasions and a decline 23 times.
In all these years that saw the Gulf Wars of the 80s and 90s, the East Asian crisis of late 90s, the 9/11 attacks and the consequent wars in Iraq and Afghanistan, the interminable battle for Jerusalem and the ongoing Arab revolution, petrol price has gone up by almost 8 times, while diesel has gone up by over 12 times. The increase in the price of LPG is even steeper.
This has largely affected the running cost of vehicles over the years. Considering that diesel is a fuel that is used widely by trucks that provide last mile connectivity in distribution and hence more internally linked to general inflation, it has seen relatively less volatility. It is also not decontrolled like petrol (last year) and hence would continue to be less prone to hikes in future.

Between the four options that are available to consumers today, a diesel car costs the maximum and a petrol the minimum. Between these two, CNG is the next most expensive followed by LPG.
However, due to its lower price and higher mileage, it is CNG with a running cost of just Rs 1.2 per kilometer that provides the most value for money followed by diesel’s 1.96 per km. As stated above, LPG is increasingly becoming a less attractive proposition with a running cost of 2.54 per kilometer, only a rupee less than a petrol car.
Diesel makes all the sense for a person who is a heavy user of cars. If somebody routinely logs 16,000 kilometers per year (national average is 13,000 kms), roughly 1300 kilometers a month, or 45 kilometers a day, a break even compared to a petrol car that would cost Rs 80,000 less could be achieved in a little over 3 years at current rates. If the person happens to drive the car for 2 more years at the same rate, he would end up with a saving of almost Rs 51,000 over a petrol car. The diesel’s case is almost similar to that of LPG, only that the latter would be less profitable if the car is kept for more than 5 years.
These numbers multiply almost 3 fold incase of a CNG vehicle. A break even could be achieved in less than a year and a half and in 5 years a saving of Rs 1.36 lakh could be made.
It is an open and shut case for those who stay in metros and have the luxury of availability of CNG, and do not mind the lack of a boot space. Driving 45 kilometers a day in a metro like Delhi, Mumbai or even Ahmedabad, is a routine affair for most. Those who do not have CNG yet, would have to settle for diesel, which it seems most are.

But those staying in mofussil small towns of the country, where driving even 10 kilometers means one is out in the hinterland, the psychology of saving that diesel gives every time one refills the vehicle is only a mirage. By the time you decide to do away with the car in 5 years after driving it for only 45,000-50,000 kilometers, you may not have saved anything at all. The good old petrol still makes sense and if perchance CNG does come calling in between, you would only be happier. Sadly, diesel and CNG don’t go hand in hand, and never will.

Petrol Engine Versus Diesel Engine

Petrol Engine Versus Diesel Engine
The choice between Petrol cars and Diesel cars is highly debated right from the inception of these two engine types. There have been endless discussions on this topic among car enthusiasts across the world including India. This article is dedicated to comparing these two most famous engine variations.
 
Differences Between Petrol and Diesel Engines
The most distinguishing feature of the diesel engine is that it uses compression ignition to burn the fuel, which is injected into the combustion chamber during the final stage of compression. In a diesel engine, fuel is injected at high pressure into the hot, compressed air in the cylinder, which causes it to burn and no spark is required for this. Thus, "compression ignition" is done rather than "spark ignition". The petrol engine is known as a "spark ignition" engine.
The Petrol engine uses the Otto cycle in which a fuel/air mixture is ignited by a spark plug. The air and fuel mixture when ignited by a spark burns and thereby expands to force the piston down. In case of a petrol engine, fuel and air are pre-mixed usually before compression. Earlier the pre-mixing used to be done in a carburetor but now (except in the smallest engines) electronically-controlled fuel injection is used for this. The pre-mixing of fuel and air makes a petrol engine to run at a much higher speed than a diesel. However, it severely limits their compression, and thus efficiency.
Diesel engines offer better fuel efficiency when compared to petrol due to the fact that they have higher compression ratio. Another advantage is that, a diesel engine can be more easily turbocharged than a petrol engine because of the fact that if the compression ratio and the pressure in the cylinder are high during the inlet stroke, the mixture starts to burn to soon, while the piston is on its way up. The diesel engine has no fuel in the cylinder and thus allows the turbocharger to suck as much air as it can without creating any problem.

 The higher compression ratio is helpful in raising fuel efficiency. Diesel engines are much more efficient than petrol engines when at low power and at engine idle. Diesel engines, unlike the petrol engine, lack a butterfly valve (throttle) in the inlet system, which closes at idle. This creates parasitic loss and destruction of availability of the incoming air, reducing the efficiency of petrol/gasoline engines at idle. This mechanism makes the diesel engine an attractive choice for many. Diesel engines are left idle for many hours or sometimes days in many applications, such as marine, agriculture, and railways. The engines are more efficient when compared to petrol engines of the same power. They consume significantly lower fuel and offer better mileage.

Engines and Emissions
Diesel engines consume around 30% less fuel than petrol engines and this results in much lesser carbon dioxide emissions. The diesel engines produce virtually no carbon monoxide and are much safer than petrol engines. Tests done on car emissions reveal that while Nitrogen Oxides are higher in a new diesel engine when compared to a new petrol engine. But by the time they cover 50,000 miles or so, they are the same and after that the petrol engine produces more Oxides than the diesel engine. Hydrocarbon emissions contained in petrol engine emissions are considerably more than that in diesel engine emissions. However, diesel is certainly more dangerous from the point of view of Suspended Particulate Matter (SPM). SPM refers to solid particles suspended in open air, such as soot generated by combustion of various fuels. They might cause respiratory problems because of their tendency to deposit themselves in the lungs. Though much has been done to improve the fuel efficiency and reduce emissions from the petrol engine, still more needs to be done.

Engine- Functions Of Important Parts In Internal Combustion Engine.

Internal combustion engines are made from various parts.Each part has its own location and function for proper working of engine.Some important parts and its function is as described below. It is most essential to know right information from engineering person.
01) Cylinder Block
Function- In the bore of cylinder the fresh charge of air-fuel mixture is ignited,compressed by piston and expanded to give power to piston.

02) Cylinder Head
Function-It carries inlet and exhaust valve.Fresh charge is admitted through inlet valve and burnt gases are exhausted from exhaust valve.In case of petrol engine,a spark plug and in case of diesel engine,a injector is also mounted on cylinder head.
03) Piston
Function-During suction stroke,it sucks the fresh charge of air-fuel mixture through inlet valve and compresses during the compression stroke inside the cylinder.This way piston receives power from the expanding gases after ignition in cylinder.Also forces the burnt exhaust gases out of the cylinder through exhaust valve.
04) Piston Rings
Function-It prevents the compressed charge of fuel-air mixture from leaking to the other side of the piston.Oil rings,is used for removing lubricating oil from the cylinder after lubrication.This ring prevents the excess oil to mix with charge.
05) Connecting Rod
Function-It changes the reciprocating motion of piston into rotary motion at crankshaft.This way connecting rod transmits the power produced at piston to crankshaft.
06) Gudgeon Pin
Function-Connects the piston with small end of connecting rod.
07) Crank Pin
Function-hand over the power and motion to the crank shaft which come from piston through connecting rod.
08) Crank Shaft
Function-Receives oscillating motion from connecting rod and gives a rotary motion to the main shaft.It also drives the camshaft which actuate the valves of the engine.
09) Cam Shaft
Function-It takes driving force from crankshaft through gear train or chain and operates the inlet valve as well as exhaust valve with the help of cam followers,push rod and rocker arms.
10) Inlet Valve & Exhaust Valve
Function-Inlet valve allow the fresh charge of air-fuel mixture to enter the cylinder bore.Exhaust valve permits the burnt gases to escape from the cylinder bore at proper timing.
11) Governor
Function-It controls the speed of engine at a different load by regulating fuel supply in diesel engine.In petrol engine,supplying the mixture of air-petrol and controlling the speed at various load condition.
12) Carburetor
Function-It converts petrol in fine spray and mixes with air in proper ratio as per requirement of the engine.
13) Fuel Pump
Function-This device supply the petrol to the carburetor sucking from the fuel tank.
14) Spark Plug
Function-This device is used in petrol engine only and ignite the charge of fuel for combustion.
15) Fuel Injector
Function-This device is used in diesel engine only and delivers fuel in fine spray under pressure.
I hope,above information will help you something about your vehicle's engine.
For more,please visit:

http://www.engihub.com/

Automobiles Engine

Automotive production down the ages has required a wide range of energy-conversion systems. These include electric, steam, solar, turbine, rotary, and different types of piston-type internal combustion engines. The reciprocating-piston internal -combustion system, operating on a four-stroke cycle, has been the most successful for automobiles, while diesel engines are widely used for trucks and buses.
The gasoline engine was originally selected for the automobile due to its flexibility over a wide range of speeds. Also, the power developed for a given weight engine was reasonable; it could be produced by economical mass-production methods; and it used a readily available, moderately priced fuel--gasoline. Reliability, compact size, and range of operation later became important factors.

In today’s world, there has been a growing emphasis on the pollution producing features of automotive power systems. This has created new interest in alternate power sources and internal-combustion engine refinements that were not economically feasible in prior years. Although a few limited-production battery-powered electric vehicles have appeared from time to time, they have not proved to be competitive owing to costs and operating characteristics. However, the gasoline engine, with its new emission-control devices to improve emission performance, has not yet been challenged significantly.

The first half of the twentieth century saw a trend to increase engine horsepower, particularly in the American models. Design changes incorporated all known methods of raising engine capacity, including increasing the pressure in the cylinders to improve efficiency, increasing the size of the engine, and increasing the speed at which power is generated. The higher forces and pressures created by these changes created engine vibration and size problems that led to stiffer, more compact engines with V and opposed cylinder layouts replacing longer straight-line arrangements. In passenger cars, V-8 layouts were adopted for all piston displacements greater than 250 cubic inches (4 litres).

Smaller cars brought about a return a to smaller engines, the four- and six-cylinder designs rated as low as 80 horsepower, compared with the standard-size V-8 of large cylinder bore and relatively short piston stroke with horsepower ratings in the range from 250 to 350.

The automobile engines from Europe had a bigger range, varying from 1to12 cylinders with corresponding differences in overall size, weight, piston displacement, and cylinder bores. Four cylinders and horsepower ratings from 19 to 120 was followed in a majority of the models. Several three-cylinder, two-stroke-cycle models were built while most engines had straight or in-line cylinders. There were several V-type models and horizontally opposed two- and four-cylinder makes too. Overhead camshafts were frequently employed. The smaller engines were commonly air-cooled and located at the rear of the vehicle; compression ratios were relatively low. The 1970s and '80s saw an increased interest in improved fuel economy which brought in a return to smaller V-6 and four-cylinder layouts, with as many as five valves per cylinder to improve efficiency. 

Engine Types

Engine Types

The engine types are usually used in the following order, depending on the number of cylinders: I-4, V-6, V-8, V-10, V-12, W-16.

Flat
Flat engines are called flat because that is exactly what they are. The cylinders lie flat. Half of the cylinders are located on one side of the crank shaft and the other half on the other side. The advantage to having your cylinders horizontal is that the engine can be placed lower in the car. This makes the car more stable because of a lower center of gravity. Being lower in the also has a space advantage. The engine bay is far less crowded. They are found in porshes and subaru's. The are also known as boxer engines. Usually Flat-4 or Flat-6.

Inline

Inline engines have cylinders on top of the crank shaft. They stand inline at a vertical 90 degrees. Inline engines run smooth and can provide a lot of power. The engines, though, are longer then any other type. In cars today, most inline engines have small cylinders so length is not an issue. Above all, Honda's and many imports of today are known for their inline 4's today. Usually I-4 or I-6 for cars. Some marine engines have been made that use the I-Engine type with up to 14 cylinders.

V-Type

V-8's and V-6's engine types exist today in many American cars and trucks. The cylinders are located on oppsite sides of the crank shaft and are elevated up a varying amount of degrees depending on the manufacturer. The V-type engine is known for using a pushrod valve system. Usually V-6, V-8, V-10, and V-12.

W-Type

W-Type engines are found in few cars. For example there is one in the Bugatti 16/4 Veyron, which has a quad-turbo W-16, and there was a limited number of Volkswagen Passat produced from 1998-2005 with a 4.0L W-8. The Bugatti 16/4 Veyron's "16/4" is there for the simple fact of representing its engine. W-engine types work well for a large number of cylinders because everything becomes more compact and shorter. Though, they are more compact, the disadvantage is that they are hard to fix and more expensive to repair. Not many models made though the engines produce go up in multiples of four. The Bugatti Veyron engine is pictured below.






Wankel

Wankel engines are also know as rotary engines. Wankel engines are completey different from any other type of automotive engines. It does not have pistons. Rather a single triangular rotor spins around a peanut shaped chamber. The triangular rotor is a special type of triangle also known as a Reuleaux triangle. This triangle has an equal diameter relative to the center at all times. The shape it is based off of an equilateral triangle. The reason this type of triangle is necessary is to ensure a seal during the triangles rotation at the center of the housing. There is a single straight shaft through the center of one of these engines that serves the purpose of a crankshaft in an otto cycle engine, otto cycle is the 4-stroke cycle in a regular pistion engine. Wankel engines are found in Mazda RX-7's and RX-8's. Pictured below is a rotary engine.

Automobiles at 20th Jan,2012

Hyundai doubles down on ad slot right before Super Bowl kickoff

Brian Steinberg

NEW YORK -- Hyundai plans to advertise during Super Bowl XLVI, but the automaker is also doubling down on the power of a commercial played just before the game begins.
Hyundai will run a 60-second ad just before kickoff on Feb. 5 on NBC, Steve Shannon, vice president of marketing at Hyundai Motor America, said in an interview. Hyundai Motor Co. has run ads in that slot in the past few years, but none as long as 60 seconds, he said.
The extra time ensures that Hyundai has "these clear seconds just before the game starts," Shannon said. He promised that the ad would be "anthemic."
Hyundai will also run two 30-second spots during the game, one in the first and one in the fourth quarter, but capturing the "pre-kick" spot means the advertiser will get the eyes of Super Bowl viewers who have seen all the pregame coverage and are primed for the start of the annual classic. Ads during the game can get lost in the action of the event, Shannon suggested, but the pre-kick moment offers clarity and is thus worth a 60-second berth.
Shannon said he hoped the pre-kick spot would plant a seed about Hyundai in viewers' minds, the better to help its two in-game ads have a more significant impact.
Before Hyundai, Pizza Hut bought the last ad before the start of the Super Bowl in an effort to get people thinking about its pizza while they were watching the game.
Hyundai has advertised in the Super Bowl since 2008 but did not start buying pre-game inventory until 2009. In 2009 and 2010, the company purchased "isopods" -- a slot devoted to their commercial -- in the moments just before kickoff.
The price for a 30-second ad berth during pregame coverage on Fox's telecast last year was between $100,000 and $2 million, depending on the proximity to kickoff, according to a person familiar with the situation.

BMW's Mini starts U.S. ad agency search

Rupal Parekh

NEW YORK -- BMW Mini is talking to ad agencies, making it the first car account up for grabs in 2012, Advertising Age, an affiliate of Automotive News, reported on Tuesday.
Independent agency Butler Shine Stern & Partners has been the agency of record since 2005.
The carmaker has started a review process by circulating a request-for-information document to a variety of shops. Hasan & Co. in Raleigh, N.C., is the consultant; the firm handled the review the last time as well.
Mini is considering new agencies for the full scope of work handled by BSSP, which includes national brand creative, regional and dealer creative, media planning and buying for both national and co-op advertising. Not included is digital work, which is handled by Boston-based Beam Interactive and multicultural marketing, handled by Austin, Texas-based Sanders Wingo.
BSSP, of Sausalito, Calif., succeeded MDC Partners' CP&B when, after four years of working on the business, it resigned the account to handle the much larger Volkswagen of America account. (VW is now working with Interpublic Group of Cos.' Deutsch, Los Angeles.)
Mandatory RFP
According to Mini, the review isn't related to performance, but is being mandated by the company's procurement department.
"Mini USA has been very satisfied with BSSP's services," Tom Salkowsky, manager of Mini USA marketing, said in a statement. "They have helped support Mini's growth over the years with groundbreaking, never-been-done-before creative. We are simply adhering to BMW Group corporate purchasing procedures by going to RFP," He noted that BSSP will participate in the review.
Said John Butler, executive creative director at BSSP, in the statement: "Generally, we believe incumbents shouldn't participate in an agency review. However, with our strong dealer and client relationships, an Effie for Mini each year that we've had the business, and the strength of the work, we are confident that we will prevail."
Despite the fact that spending isn't huge, agencies will likely jump at the chance to participate given the brand is high-profile and auto accounts are still a status symbol on Madison Avenue.
According to Kantar, in 2010, the most recent full year for data, BMW spent more than $165 million in domestic measured media. Of that amount, it devoted about $26 million to marketing Mini. That number is on track to be about the same or slightly lower for 2011, according to Kantar.
Its latest advertising, themed "The Best Test Drive Ever. Period," featured the winner of a contest who submitted a six-word description of his idea of the best-ever test drive. The winner is featured in a two-minute film and 90-second cinema commercial dramatizing his idea.
Perplexing decision
Although it's a mandated review, the decision to call a pitch now is still perplexing, considering how well the brand is performing.
BMW's Mini brand remains a niche player in the U.S. auto market, even though it fields a range of five different models, with a sixth, a two-seat roadster, coming later this year. Mini added the two-seat coupe and the crossover Countryman last year, and for all of 2011, the brand, helped by the new models, sold 57,511 units, up 26 percent from the previous year in the United States, according to the Automotive News data center.
Mini's marketing has emphasized the brand's fuel efficiency and its sporting character, as well as its option choices across the range.
The review follows agency changes made by BMW for its BMW North America and Rolls Royce brands, which were both moved to MDC Partners' KBS&P last year. It also comes as the brand is facing recall challenges; almost 90,000 Mini Coopers and other Mini brand vehicles are being recalled in the U.S. due to potentially problematic water pumps that could spark engine fires.
Stephen Williams contributed to this report.

Daimler vs. Lieb; next round in April

Harald Hamprecht is Editor-in-Chief at Automotive News Europe.

Fired Mercedes-Benz USA boss Ernst Lieb's wrongful-dismissal lawsuit is set to be heard in a Stuttgart court on April 12. Lieb will challenge allegations contained in Daimler's response to that suit that he improperly used more than $100,000 in company funds to upgrade the Mercedes-owned U.S. home in Mahwah, New Jersey, where he lived.
Lieb's lawyer, Stefan Naegele, plans to show that the 56-year-old executive was one of dozens of Mercedes executives who has been fired unfairly as part of parent Daimler's wide-reaching "zero tolerance" crackdown on ethics violations.
"None of the accusations are justified. And we will prove that," Naegele told Automotive News Europe in a telephone interview in late December.
Daimler fired Lieb in late October ending his five-year run as CEO. During a Nov. 29 preliminary hearing, Daimler alleged that Lieb used company money to pay for items such as a home theater system, home gym, washer, dryer and built-in barbecue system. A Daimler spokesman added that Lieb was fired because he "made incomplete, inaccurate and manipulative statements to the company and the responsible persons" during a company audit of spending by overseas executives.
My suggestion to both parties: Get this settled as quickly and quietly as possible. The longer this drags on the worse it will be for the image of both sides.

Jet Engine

Jet Engine 
 A jet engine is a heat engine that is propelled in a forward direction as the result of the escape of hot gases from the rear of the engine. In an airbreathing jet engine, air entering the front of the engine is used to burn a fuel within the engine, producing the hot gases needed for propulsion (forward movement). Jet engines are used for the fastest commercial and military aircraft now available.

Scientific principle behind jet engines

The scientific principle on which the jet engine operates was first stated in scientific terms by English physicist and mathematician Isaac Newton (1642–1727) in 1687. According to Newton's third law of motion, for every action there is an equal and opposite reaction. That principle can be illustrated by the behavior of a balloon filled with air. If the neck of the balloon is untied, gases begin to escape from the balloon. The escape of gases from the balloon is, in Newton's terms, an "action." The equal and opposite reaction resulting from the escape of gases is the movement of the balloon in a direction opposite to that of the movement of the gases. That is, as the air moves to the rear, the balloon moves forward.

Types of jet engines

Ramjets. The simplest of all jet engines is the ramjet. The ramjet consists of a long cylindrical metal tube open at both ends. The tube bulges in the middle and tapers off at both ends. As the engine moves forward at high speeds, the air entering it is automatically compressed (made more compact under pressure). The compressed air is then used to burn a fuel, usually a kerosene-like material. The hot gases produced during combustion within the engine are then expelled out the back of the engine. As the gases leave the back of the jet engine (the nozzle exit), they propel the engine—and the wing and airplane to which it is attached—in a forward direction.
A typical ramjet engine today has a length of about 13 feet (4 meters), a diameter of about 39 inches (1 meter), and a weight of about 1,000 pounds (450 kilograms). A ramjet engine of this design is capable of giving a maximum velocity of about Mach 4 (Mach 1 is equal to the speed of sound: 740 miles [1190 kilometers] per hour).


Turbojets. A turbojet differs from a ramjet in that it contains a compressor attached to a turbine. The compressor consists of several rows of metal blades attached to a central shaft. The shaft, in turn, is attached to a turbine at the rear of the compressor. When air enters the inlet of a turbojet engine, some of it is directed to the core of the engine where the compressor is located. The compressor reduces the volume of the air and sends it into the combustion chamber under high pressure.
The exhaust gases formed in the combustion chamber have two functions. They exit the rear of the chamber, as in a ramjet, providing the engine with a forward thrust. At the same time, the gases pass over the blades of the turbine, causing it to spin on its axis. The spinning turbine operates the compressor at the front of the engine, making possible the continued compression of new incoming air. Unlike a ramjet engine, which only operates after a high speed has been attained, the turbojet engine operates continuously.

Turboprop engines. In a turboprop engine, a conventional propeller is attached to the turbine in a turbojet engine. As the turbine is turned by the series of reactions described above, it turns the airplane's propeller. Much greater propeller speeds can be attained by this combination than are possible with simple piston-driven propeller planes. However, propellers cannot operate at high air speeds. The maximum efficient speed at which turboprop airplanes can operate is less than 450 miles (724 kilometers) per hour.
 
Afterburners. No more than about one-quarter of all the oxygen entering the front of the jet engine is actually used to burn fuel within the engine. To make the process more efficient, some jet engines are also equipped with an afterburner. The afterburner is located directly behind the turbine in the jet engine. It consists of tubes out of which fuel is sprayed into the hot exhaust gases exiting the tubing. Combustion takes place in the afterburner, as it does in the combustion chamber, providing the engine with additional thrust.

Diesel engine

A diesel engine is a type of internal-combustion engine developed by German engineer Rudolf Diesel (1858–1913) in the late nineteenth century. His original design called for the use of coal dust as fuel, but most modern diesel engines burn low-cost fuel oil. Whereas gasoline engines (found in the majority of present-day automobiles) use an electric spark to ignite the premixed fuel-air blend, diesel engines use compressed air to ignite the fuel.
In both gasoline and diesel engines, fuel is ignited in a cylinder, or chamber. Inside the sealed, hollow cylinder is a piston (a solid cylinder) that is attached at the bottom to a crankshaft. The movement of the piston up and down turns the crankshaft, which transfers that movement through various gears to the drive wheels in an automobile.

In a diesel engine cylinder, the piston completes one up-and-down cycle in four strokes: intake, compression, power, and exhaust. During the intake stroke, the piston moves downward, sucking air into the cylinder through an open intake valve. On the compression stroke, the intake valve closes and the piston rises, compressing the air in the cylinder and causing it to become heated. While the air is being compressed, a fuel pump sprays fuel into the cylinder to mix with the air. When the compressed, hot air reaches the right temperature, it ignites the fuel, driving the piston down on the power stroke. As the piston rises on the exhaust stroke, the exhaust valve opens and the gases created by explosion of the fuel (exhaust) pass out of the cylinder. Then the cycle repeats.

The entire combustion cycle takes but a fraction of a second. Diesel engines can operate from several hundred up to almost one thousand revolutions per minute. The high pressure created in the cylinders during compression requires diesel engines to be strongly constructed and, thus, much heavier than gasoline engines. This weight cuts into their fuel efficiency. Diesel engines also emit high levels of foul-smelling exhaust.
However, diesel engines are more powerful than conventional gasoline engines and run on a less costly fuel. First installed on a ship in 1910 and in an automobile in 1922, they are generally used in large vehicles such as locomotives, trucks, and buses, and in heavy construction and agricultural machinery. Because of their ability to burn crude fuels while delivering an efficient amount of the fuel's energy as usable power, diesel engines are almost the only choice for industrial power throughout the world.

Combustion Engine

Combustion Engine

The invention and development of the internal-combustion engine in the nineteenth century has had a profound impact on human life. The internal-combustion engine offers a relatively small, lightweight source for the amount of power it produces. Harnessing that power has made possible practical machines ranging from the smallest model airplane to the largest truck. Lawnmowers, chainsaws, and electric generators also may use internal-combustion engines. An important device based on the internal-combustion engine is the automobile.
In all internal-combustion engines, however, the basic principles remain the same. Fuel is ignited in a cylinder, or chamber. Inside the sealed, hollow cylinder is a piston (a solid cylinder) that is free to move up and down and is attached at the bottom to a crankshaft. The energy created by the combustion, or burning, of the fuel pushes down on the piston. The movement of the piston turns the crankshaft, which then transfers that movement through various gears to the desired destination, such as the drive wheels in an automobile.

Basic principles

The most common internal-combustion engines are the piston-type gasoline engines used in most automobiles. In an engine, the cylinder is housed inside an engine block strong enough to contain the explosions of fuel. Inside the cylinder is a piston that fits the cylinder precisely. Pistons generally are dome-shaped on top, and hollow at the bottom. In a four-stroke engine, the piston completes one up-and-down cycle in four strokes: intake, compression, power, and exhaust.
The first stroke, the intake stroke, begins when the piston is at the top of the cylinder, called the cylinder head. As it is drawn down, it creates a vacuum in the cylinder. This is because the piston and the cylinder form an airtight space. This vacuum helps to draw the fuel-air mixture into the cylinder through an open intake valve, which closes when the piston reaches the bottom of the cylinder.
On the next stroke, called the compression stroke, the piston is pushed up inside the cylinder, compressing or squeezing the fuel-air mixture into a tighter and tighter space. The compression of the mixture against the top of the cylinder causes the air to heat up, which in turn heats the mixture. Compressing the fuel-air mixture also makes it easier to ignite and makes the resulting explosion more powerful. There is less space for the expanding gases of the explosion to flow, which means they will push harder against the piston in order to escape.
At the top of the compression stroke, the fuel-air mixture is ignited by a spark from a spark plug placed in the cylinder head, causing an explosion that pushes the piston down. This stroke is called the power stroke, and this is the stroke that turns the crankshaft.
The final stroke, the exhaust stroke, takes the piston upward again, expelling the exhaust gases created by the explosion from the cylinder through an exhaust valve. When the piston reaches the top of the cylinder, it begins the four-step process again.

Development of the internal-combustion engine

In 1824, French physicist Nicholas Carnot (1796–1832) published a book that set out the principles of an internal-combustion engine that would use an inflammable mixture of gas vapor and air. Basing his work
on Carnot's principles, another Frenchman named Jean-Joseph-Étienne Lenoir (1822–1900) presented the world with its first workable internal-combustion engine in 1859. Lenoir's motor was a two-cycle (two-stroke), one-cylinder engine with slide valves that used coal gas as a fuel. A battery supplied the electrical charge to ignite the gas after it was drawn into the cylinder. In 1862, another Frenchman, Alphonse-Eugène Beau de Rochas (1815–1893), designed a four-stroke engine that would overcome many problems associated with the gas engines of that time.
Two-stroke engines eliminate the intake and exhaust strokes, combining them with the compression and power strokes. This allows for a lighter, more powerful engine—relative to the engine's size—requiring a less complex design. But the two-stroke cycle is a less efficient method of burning fuel. A residue of unburned fuel remains inside the cylinder, which hinders combustion. The two-stroke engine also ignites its fuel twice as often as a four-stroke engine, which increases the wear on the engine's parts. Two-stroke engines are therefore used mostly where a smaller engine is required, such as on some motorcycles and with small tools.
An internal-combustion engine can have anywhere from one to twelve or more cylinders, all acting together in a precisely timed sequence to drive the crankshaft. Automobiles generally have four-, six-, or eight-cylinder engines, although two-cylinder and twelve-cylinder engines are also available. The number of cylinders affects the engine's displacement, that is, the total volume of fuel passed through the cylinders. A larger displacement allows more fuel to be burned, creating more energy to drive the crankshaft.
In the case of an engine with two or more cylinders, however, the spark from the spark plugs must be directed to each cylinder in turn. The sequence of firing the cylinders must be timed so that while one piston is in its power stroke, another piston is in its compression stroke. In this way, the force exerted on the crankshaft can be kept constant, allowing the engine to run smoothly. The number of cylinders affects the smoothness of the engine's operation: the more cylinders, the more constant the force on the crankshaft and the more smoothly the engine will run.
In addition to piston-driven, gas-powered internal-combustion engines, other internal-combustion engines have been developed, such as the Wankel engine and the gas turbine engine. Jet engines and diesel engines are also powered by internal combustion.

Sciensc Automobile Technologies

Automobiles
Automobiles or motor car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor. Most definitions of the term specify that automobiles are designed to run primarily on roads, to have seating for one to eight people, to typically have four wheels, and to be constructed principally for the transport of people rather than goods. However, the term automobile is far from precise, because there are many types of vehicles that do similar tasks.

As of 2002, there were 590 million passenger cars worldwide. Around the world, there were about 806 million cars and light trucks on the road in 2007; they burn over 260 billion gallons of gasoline and diesel fuel yearly. The numbers are increasing rapidly, especially in China and India. 

Advantages and Disadvantages of Having Your Own Automobile

An automobile is a transport vehicle that has an engine and fuel to move. Owning a car gives us more convenience than riding on a public transport. There is a freedom in an individual. You can easily gain friends. Furthermore, you are highly appreciated by others.

For business people, automobile is part of their business. The fast and easy way of going out for a meeting and the transport of goods from one place to another. However, there are times you need to rent a car due to business travel. You are in need to visit other places for business purposes. Of course, you are in need of rent a car service. There are a lot of them. You should research on where you can find the best rent a car service. It should fit your requirement also.

We should also not forget to construct roads for them. It is very much important to cars because damaged roads are not good passageways for cars.

There are more supermarkets, department stores, resorts and a lot more establishments were built because people can travel far places fast and easy. Moreover, eqiupments and services needed by automobiles are increasing.

We should be more particular also of the bad effects of automobiles? Don't you know that automobiles are the number 1 cause of air pollution and noise pollution. It is really bad for the health. Accidents are prone. There were many injured and died because of car accidents.