Buick Small-Block

In 1961 Buick unveiled an entirely new small V8 engine with aluminum cylinder heads and cylinder block. Lightweight and powerful, the aluminum V8 also spawned a turbocharged version, (only in the 1962-63 Oldsmobile Cutlass version), the first ever offered in a passenger car. It became the basis of a highly successful cast iron V6 engine, the Fireball. The all-aluminum engine was dropped after the 1963 model year, but was replaced with a very similar cast-iron engine.


215

GM experimented with aluminum engines starting in the early 1950s, and work on a production unit commenced in 1956. Originally intended for 180 in³ (2.9 L) displacement, Buick was designated by GM as the engine design leader, and decided to begin with a larger, 215 in³ (3.5 L) size, which was deemed ideal for the new "senior compact cars" introduced for the 1961 model year. This group of cars was commonly called the BOP group or A-bodies.

The 215 had a 4.24 in (107.7 mm) bore spacing, a bore of 3.5 in (88.9 mm), and a stroke of 2.8 in (71.1 mm), for an actual displacement of 3533 cc. The engine was the lightest mass-production V8 in the world, with a dry weight of only 318 lb (144 kg). It was standard equipment in the 1961 Buick Special.

Oldsmobile and Pontiac also used the all-aluminum 215 on its mid-sized cars, the Oldsmobile F-85 and Pontiac Tempest. However the Oldsmobile version of this engine, although sharing the same basic architecture, had cylinder heads designed by Oldsmobile engineers, and was produced on a separate assembly line. Among the differences between the Oldsmobile and Buick versions, it was somewhat heavier, at 350 lb (159 kg). The design differences were in the cylinder heads: Buick used a 5-bolt pattern around each cylinder where Oldsmobile went to a 6-bolt pattern. The 6th bolt was added to the intake manifold side of the head, one extra bolt for each cylinder. This was supposed to alleviate the head-warping problems that came about on the higher compression ratio versions. Later Rover versions of the aluminum block and subsequent Buick iron small blocks (300, 340 and 350) went to a 4 bolt per cylinder pattern.

At introduction, Buick's 215 was rated 150 hp (112 kW) at 4400 rpm. This was raised soon after introduction to 155 hp (116 kW) at 4600 rpm. 220 ft·lbf (298 N·m) of torque was produced at 2400 rpm with a Rochester 2GC two-barrel carburetor and 8.8:1 compression ratio. A mid-year introduction was the Buick Special Skylark version, which had 10.25:1 compression and a four-barrel carburetor, raising output to 185 hp (138 kW) at 4800 rpm and 230 ft·lbf (312 N·m) at 2800 rpm.

For 1962, the four-barrel engine increased compression ratio to 11.0:1, raising it to 190 hp (142 kW) at 4800 rpm and 235 ft·lbf (319 N·m) at 3000 rpm. The two-barrel engine was unchanged. For 1963 the four-barrel was bumped to an even 200 hp (149 kW) at 5000 rpm and 240 ft·lbf (325 N·m) at 3200 rpm, a respectable 0.93 hp/in³ (56.6 hp/liter).

Unfortunately, the great expense of the aluminum engine led to its cancellation after the 1963 model year. The engine had an abnormally high scrap ratio due to hidden block-casting porosity problems, which caused serious oil leaks. Another problem was clogged radiators from antifreeze mixtures incompatible with aluminum. It was said that one of the major problems was because they had to make extensive use of air gaging to check for casting leaks during the manufacturing process, and not being able to detect leaks on blocks that were as much as 95% complete. This raised the cost of complete engines to more than that of a comparable all cast-iron engine. Casting sealing technology was not advanced enough at that time to prevent the high scrap rates.

The Buick 215's very high power to weight ratio made it immediately interesting for automotive and marine racing. Mickey Thompson entered a stock-block Buick 215-powered car in the 1962 Indianapolis_500. From 1946 to 1962 there hadn't been a single stock-block car in this famous race. In 1962 the Buick 215 was the only non-Offenhauser powered entry in the field of 33 cars. Rookie driver Dan_Gurney qualified eighth and raced well for 92 laps before retiring with transmission problems.

Surplus engine blocks of the Oldsmobile (6 bolt per cylinder) version of this engine formed the basis of the Formula One Repco V8 used by Brabham to win the 1966 and 1967 Formula One championship. No other American stock-block engine has won a Formula One championship.

Buick 215s have been engine swapped into countless sports cars including especially Chevrolet Vegas and MG sports cars. The engine remains well supported by enthusiast clubs, specialist parts suppliers, and by shops that specialize in these conversions.

The Buick 215 was used in a small sports car known as the Apollo from 1962 to 1963, and also in the Asardo 3500 GM-S show car.

Although dropped by GM in 1963, in January 1965 the tooling for the aluminum engine was sold to Britain's Rover Group to become the Rover V8 engine, which would remain in use for more than 35 years. GM tried to buy it back later on, but Rover declined, instead offering to sell engines back to GM. GM refused this offer.


300

In 1964 Buick replaced the 215 with an iron-block engine of very similar architecture. The new engine had a bore of 3.75 in (95.5 mm) and a stroke of 3.40 in (86.4 mm) for a displacement of 300.4 cu. in. (4.9 L). It retained the aluminum cylinder heads, intake manifold, and accessories of the 215 for a dry weight of 405 lb (184 kg). The 300 was offered in two-barrel form, with 9.0:1 compression, making 210 hp @ 4600 rpm and 310 ft·lbf @ 2400 rpm, and four-barrel form, with 11.0:1 compression, making 250 hp @ 4800 rpm and 335 ft·lbf @ 3000 rpm.

For 1965 the 300 switched to a cast-iron heads, raising dry weight to 467 lb (212 kg), still quite light for a V8 engine of its era. The four-barrel option was cancelled for 1966, and the 300 was replaced entirely by the 350 in 1968.

The Apollo sports car, also known as the Vetta Ventura, used this engine.


340

The 340 in³ (5.6 L) 340 was a stroked (to 3.85 in/97.8 mm) version of the 300. It had a two-barrel or four-barrel carburetor, the two barrel with 220 hp, and the four barrel with 11.0:1 compression, rated at 260 hp @ 4200 rpm and 365 ft·lbf @ 2800 rpm. It replaced the four-barrel 300 for 1966. It was produced only in 1966 and 1967, with the new Buick 350 taking its place after that.


350

Buick adopted the popular 350 in³ (5.7 L) size with their final family of V8s. Although sharing the displacement of the Chevrolet Small-Block engine family, the Buicks were substantially different.

The Buick 350 V8 had a 3.80 in bore (like the 231) and retained the 3.85 in stroke of the 340. It was introduced in 1968 and produced through 1980.

The major differences of the Buick 350 when compared to other GM V8's are, deep skirt block construction, higher nickel-content cast iron, external oil pump, under square bore sizing, 3.0" crank main journals, and 6.5" connecting rods. It is an extremely rugged and durable engine, and some of the design characteristics of the Buick 350 are found in modern GM engines such as the 231 V6, and Series I, II, and III 3800 V6's.

Of all the GM 350-inch engines, the Buick 350 has the longest stroke, which lends to making significantly more torque than any of the others. It also made the Buick 350 significantly wider - essentially the same width as the Buick big-blocks, which have the shortest stroke of the GM big-blocks. In fact, at a glance the buick 350 is commonly mistaken for the 455 engine due to the oversized intake manifold atop the engine. The Buick 350 also shares an integrated Aluminum timing cover as do most of the Buick small & big blocks that incorporates the oil pump mechanisms as well. Leaving the oil filter exposed to oncoming air for added cooling.

The Buick 350 was used in the Jeep Gladiator and Wagoneer from 1968 to 1971.

History of Petroleum electric hybrid vehicle

In 1898 Ferdinand Porsche designed the Lohner-Porsche carriage, a series-hybrid vehicle that broke several Austrian speed records, and also won the Exelberg Rally in 1901 with Porsche himself driving. Over 300 of the Lohner-Porsche carriages were sold to the public. As a series-hybrid, a gasoline engine powers a generator, which powered electric wheel motors. A large and heavy battery pack acted as an intermediate load-leveling device.

The 1915 Dual Power made by the Woods Motor Vehicle electric car maker had a four cylinder internal combustion engine and an electric motor. Below 15 mph (25 km/h) the electric motor alone drove the vehicle, drawing power from a battery pack, and above this speed the "main" engine cut in to take the car up to its 35 mph (55 km/h) top speed. About 600 were made up to 1918.

There have also been air engine hybrids where a small petrol engine powered a compressor. Several types of air engines also increased the range between fill-ups with up to 60% by absorbing ambient heat from its surroundings.

In 1959 the development of the first transistor-based electric car—the Henney Kilowatt—heralded the development of the electronic speed control that paved the way for modern hybrid electric cars. The Henney Kilowatt was the first modern production electric vehicle and was developed by a cooperative effort between National Union Electric Company, Henney Coachworks, Renault, and the Eureka Williams Company. Although sales of the Kilowatt were dismal, the development of the Kilowatt served was a historical "who's who" of electric propulsion technology.

A more recent working prototype of the electric-hybrid vehicle was built by Victor Wouk (one of the scientists involved with the Henney Kilowatt and also brother of author Herman Wouk ). Wouk's work with electric hybrid vehicles in the 1960s and 1970s earned him the title as the "Godfather of the Hybrid"). Wouk installed a prototype electric-hybrid drivetrain into a 1972 Buick Skylark provided by GM for the 1970 Federal Clean Car Incentive Program, but the program was killed by the EPA in 1976 while Eric Stork, the head of the EPA at the time, was accused of a prejudicial coverup[5]. Since then, hobbyists have continued to build hybrids but none was put into mass production by a major manufacturer until the waning years of the twentieth century.

The regenerative-braking hybrid, the core design concept of most production hybrids, was developed by Electrical Engineer David Arthurs around 1978 using off-the shelf components and an Opel GT. However the voltage controller to link the batteries, motor (a jet-engine starter motor), and DC generator was Mr. Arthurs'. The vehicle exhibited ~75 mpg fuel efficiency and plans for it (as well as somewhat updated versions) are still available through the Mother Earth News web site. The Mother Earth News' own 1980 version claimed nearly 84 mpg.

The Bill Clinton administration initiated the Partnership for a New Generation of Vehicles (PNGV)[6] program on September 29, 1993 that involved Chrysler, Ford, General Motors, USCAR, the DoE, and other various governmental agencies to engineer the next efficient and clean vehicle. The NRC cited automakers’ moves to produce hybrid electric vehicles as evidence that technologies developed under PNGV were being rapidly adopted on production lines, as called for under Goal 2. Based on information received from automakers, NRC reviewers questioned whether the “Big Three” would be able to move from the concept phase to cost effective, pre-production prototype vehicles by 2004, as set out in Goal 3.

The program was replaced by the hydrogen focused FreedomCAR initiative of George W. Bush's administration in 2001. The focus of the FreedomCAR initiative being to fund research too high risk for the private sector to engage in with the long term goal of developing emission / petroleum free vehicles.

In the intervening period, the widest use of hybrid technology was actually in diesel-electric locomotives. It is also used in diesel-electric submarines, which operate in essentially the same manner as hybrid electric cars. However, in this case the goal was to allow operation underwater without consuming large amounts of oxygen, rather than economizing on fuel. Since then, many submarines have moved to nuclear power, which can operate underwater indefinitely, though a number of nations continue to rely on diesel-electric fleets.

Automotive hybrid technology became successful in the 1990s when the Honda Insight and Toyota Prius became available. These vehicles have a direct linkage from the internal combustion engine to the driven wheels, so the engine can provide acceleration power. The 2000s saw development of plug-in hybrid electric vehicles (PHEVs), which can be recharged from the electrical power grid and do not require conventional fuel for short trips. The Renault Kangoo was the first production model of this design, released in France in 2003. However, the environmental benefits of plug-in hybrids depend somewhat on the source of the electrical power. In particular, electricity generated with wind would be cleaner than electricity generated with coal, the most polluting source. On the other hand, electricity generated with coal in a central power plant is still much cleaner than pure gasoline propulsion, due to the much greater efficiencies of a central plant. Furthermore, coal is only one source of centrally generated power, and in some places such as California is only a minor contributor, overshadowed by natural gas and other cleaner sources.

The Prius has been in high demand since its introduction. Newer designs have more conventional appearance and are less expensive, often appearing and performing identically to their non-hybrid counterparts while delivering 50% better fuel efficiency. The Honda Civic Hybrid appears identical to the non-hybrid version, for instance, but delivers about 50 US mpg (4.7 L/100km). The redesigned 2004 Toyota Prius improved passenger room, cargo area, and power output, while increasing energy efficiency and reducing emissions. The Honda Insight, while not matching the demand of the Prius, is still being produced and has a devoted base of owners. Honda has also released a hybrid version of the Accord.

2005 saw the first hybrid sport utility vehicle (SUV) released, Ford Motor Company's Ford Escape Hybrid. Toyota and Ford entered into a licensing agreement in March 2004 allowing Ford to use 20 patents from Toyota related to hybrid technology, although Ford's engine was independently designed and built. In exchange for the hybrid licenses, Ford licensed patents involving their European diesel engines to Toyota. Toyota announced model year 2005 hybrid versions of the Toyota Highlander and Lexus RX 400h with 4WD-i which uses a rear electric motor to power the rear wheels negating the need for a differential. Toyota also plans to add hybrid drivetrains to every model it sells in the coming decade.

For 2007 Lexus offers a hybrid version of their GS sport sedan dubbed the GS450h with "well in excess of 300hp". The 2007 Camry Hybrid becomes available starting Summer 2006 in USA and Canada. The initial batch of Camry Hybrids are built in Japan; starting October 2006, Toyota Motor Manufacturing, Kentucky (TMMK) will also produce these hybrids. Also, Nissan announced the release of the Altima hybrid (technology supplied by Toyota) around 2007.

An R.L. Polk survey of 2003 model year cars showed that hybrid car registrations in the United States rose to 43,435 cars, a 25.8% increase from 2002 numbers. California, the nation's most populous state at one-eighth of the total population, had the most hybrid cars registered: 11,425. The proportionally high number may be partially due to the state's higher gasoline prices and stricter emissions rules, which hybrids generally have little trouble passing.

Honda, which offers Insight, Civic and Accord hybrids, sold 26,773 hybrids in the first 11 months of 2004. Toyota has sold a cumulative 306,862 hybrids between 1997 and November 2004, and Honda has sold a total of 81,867 hybrids between 1999 and November 2004.

Motronic

Bosch Motronic was one of the first digital engine-management systems. The idea behind it was to fully integrate and regulate all major engine system parameters, thereby enabling fuel delivery and spark timing control functions to be controlled by the same unit, in an attempt to achieve optimum efficiency, driveability and power output potential.

The early Motronic systems integrated spark timing control with existing Jetronic fuel injection systems, such as L-Jetronic, LH-Jetronic, K-Jetronic, and in some cases Mono-Jetronic. It was originally developed and first used in the BMW 7 Series, before being implemented on several Volvo and Porsche engines throughout the 1980s.

The components of the Motronic 1.x systems for the most part remained unchanged during production, although there are some differences in certain situations. The electronic control unit (ECU) receives information regarding engine speed and position, crankshaft angle, coolant temperature and throttle position.

An air flow meter is used to measure the volume of air entering the induction system, and a charge air temperature sensor monitors the temperature of the inducted air after it has passed through the turbocharger and the intercooler, in order to accurately calculate the overall air mass.

A separate constant idle speed (CIS) system monitors and regulates base idle speed, depending if an interior electrical component is in operation. A cold start (5th) injector is used to provide extra fuel enrichment during different cold-start conditions.

1. ^ 25 years of Bosch Motronic: Think tank under the bonnet, Bosch, may 2004

Napier Nomad engine (aircraft engine)

The Nomad was a complex Diesel cycle aircraft engine from Napier & Son of the UK. The Nomad used a turbine to recover power from the exhaust of the otherwise conventional Diesel engine, resulting in a specific fuel consumption that remains unmatched by an aircraft engine 50 years later.


History

In 1945 the Air Ministry asked for proposals for a new 6,000 horsepower (4,500 kW) class engine with good economy. Curtiss-Wright was designing an engine of this sort of power known as the "turbo-compound", but Sir Harry Ricardo, one of Britain's great engine designers, suggested that the most economical combination would be a similar design using a diesel two-stroke in place of the Curtiss's petrol engine.

Prior to World War II Napier had licensed the Junkers Jumo 204 diesel design to set up production in the UK as the Napier Culverin, however the start of the war made the Sabre all-important and work on the Culverin was stopped. In response to the Air Ministry requirements they dusted off this work, combining two enlarged Culverins into an H-block similar to the Sabre, resulting in a massive 75 litre design. Markets for an engine of this size seem limited however, and instead they returned to the original Culverin-like horizontally opposed 12 cylinder design, resulting in the Nomad.

Design

The Nomad design was incredibly complex, essentially two engines in one. One was a supercharged Diesel similar to the Culverin. Below this was a complete turboprop engine, based on their Naiad design. The output of the turboprop was geared to a shaft running inside the Diesel's, driving the front propeller of a contra-rotating pair. As if that were not enough, during takeoff additional fuel was dumped into the rear turbine stage for additional power, and turned off once the plane was cruising.

The compressor and turbine assemblies of the Nomad 1 were tested during 1948, and the complete unit was run in October 1949. The prototype was installed in the nose of an Avro Lincoln bomber for testing, and first flew in 1950. In total the Nomad 1 ran for just over 1,000 hours, and proved to be rather temperamental, but when running properly it could produce 3000 hp (2,200 kW) and 320 lbf (1.4 kN) thrust. It had a specific fuel consumption (sfc) of 0.36 lb/(hp·h) (0.22 kg/(kW·h)).

Even before the Nomad 1 was running, its replacement, the Nomad 2, had already been designed. In this version an extra compressor stage was added, replacing the original supercharger. This stage was driven by an additional stage in the turbine, so the system was now more like a turbocharger and the compressed air for the Diesel was no longer "robbing" power. In addition the propeller shaft from the turbine was eliminated, and geared using a hydraulic clutch into the main shaft. The result was smaller and considerably simpler, a single engine driving a single propeller.

While the Nomad 2 was undergoing testing, a prototype Avro Shackleton was lent to Napier as a testbed. The engine proved bulky, like the Nomad 1 before it, and in the meantime several dummy engines were used on the Shackleton for various tests. By 1954 interest in the Nomad was dropping, and after the only other project based on it was cancelled, work on the engine was ended in April 1955.


Specifications (Nomad 2)

General characteristics

* Type: Twelve-cylinder liquid-cooled horizontally opposed Diesel combined with a turboprop aircraft engine
* Bore: 6 in (152 mm)
* Stroke: 7.375 in (187 mm)
* Displacement: 2,502 in³ (41 L)
* Dry weight: 3,580 lb (1,624 kg)

Components

* Cooling system: Liquid-cooled

Performance

* Power output: 3,135 ehp (2,338 kW) max take-off at 89 psia (614 kPa) including thrust power from the turbine
* Specific power: 1.25 ehp/in³ (57.0 kW/L)
* Compression ratio:
o Engine 8:1
o Turboprop compressor 8.25:1
* Specific fuel consumption: 0.345 lb/(ehp·h) (0.210 kg/(kW·h))
* Power-to-weight ratio: 0.88 ehp/lb (1.44 kW/kg)

Whats a Stationary engine

A stationary engine is an engine whose framework does not move. It is normally used not to propel a vehicle but to drive a piece of immobile equipment such as a pump or power tool.

This article concentrates on oil-burning or internal combustion engines;
steam-powered engines are described separately in stationary steam engine.


Overview

Stationary engines come in a wide variety of sizes and use a wide variety of technologies. These include:

* Power stations of all sizes.

* Beam engines used in mills and factories before the widespread use of electric power.

* Winding engines used at mine pitheads.


Railways

In Victorian era railway engineering, many attempts were made to replace locomotives by stationary engines, on the grounds that it was inefficient to move something as large and heavy as a steam engine around. These attempts only succeeded where short distances were to be covered, where various kinds of cable railway were successful, particularly for steep inclines (where the inefficiency of moving the engine up and down a hill is particularly significant). A heroic failure was Isambard Kingdom Brunel's attempt to construct an atmospheric railway from Exeter to Plymouth in Devon, England.

Cable haulage did prove viable where the gradients were exceptionally steep, such as the 1 in 8 gradients of the Cromford and High Peak Railway opened in 1830. Cable railways generally have two tracks with loaded wagons on one track partially balanced by empty wagons on the other, to minimise fuel costs for the stationary engine.


Farms

Small stationary engines were frequently used on a farm to drive various kinds of power tools and equipment such as circular saws, pumps, and hay elevators. The engine was fitted to a wooden trolley with steel wheels so that it could be moved to where required, and was then coupled to the equipment by means of a flat belt.

The engines were usually powered by gasoline, but in some cases for economy it was possible to switch over to run on paraffin after the engine had warmed up - to achieve this required a part of the inlet tract to be heated by exhaust gases in order to vaporise the less volatile fuel. Very large stationary engines ran on a heavier type of fuel oil, but this type of engine was usually too large to be moved; typical applications were electricity generation and large-scale pumping.

Initially, such engines mirrored steam engine design in having the piston move horizontally, with the crank and valve gear exposed and employed a drip-feed total loss lubrication system. Later for safety, cleanliness and longevity the design moved towards enclosing the working parts and using sump lubrication.

The four-stroke cycle design was by far the most common, but Petter, a British manufacturer, developed a successful two-stroke cycle design.

A centripetal governor system was usually incorporated to regulate the engine's speed under varying loads. This is a simple negative feedback control system. The engine speed is sensed by a pair of weights that rotate with the crankshaft. As the speed increases, centripetal force causes the weights to move outward against the pressure of a retaining spring. This outward movement is used to restrict the engine power to limit the speed. If the engine slows down, the centrifugal force reduces and the weights are pulled inward by spring pressure, and this movement is used to increase the engine power to maintain speed under increasing load.

The governor can use one of two techniques for controlling speed. Today, most governors open and close a butterfly valve to control the amount of fuel-air mixture entering the engine. However, in earlier engines, the governor would cut off the fuel air mixture completely. These engines are often called "hit and miss" (variously called "hit or miss") because they do not fire on every available power stroke. When the engine is running above a certain rpm, the exhaust valve is held open, and the magneto is prevented from generating a spark. Once the speed drops, the governor allows the exhaust valve to close and the magneto to fire. The engine fires and speeds back up, causing the governor to keep the exhaust valve open again.

On a medium size engine such as a 6hp, the engine can be adjusted so that it only fires every 10 seconds or so when it is not under load. These engines generally drove a wide flat belt to run a firewood cutoff saw, a pump, a reciprocating log saw, etc.

Eventually such engines were rendered obsolete by the development of electrically powered tools, and by newer gasoline engines that were small and economical enough to be permanently built in to each piece of equipment.

Live steam models of stationary engines are popular among collectors and hobbyists.

Hot bulb engine Differences from the Diesel Engine

The hot-bulb engine is often confused with the diesel engine, and it is true that the two engines are very similar. Aside from the obvious lack of a hot-bulb vaporiser in the diesel engine, the main differences are that:

* The hot-bulb engine uses both compression-ignition and the heat retained in the vaporiser to ignite the fuel.

* The diesel engine uses just compression-ignition to ignite the fuel, and it operates at pressures many times higher than the hot-bulb engine.

Due to the much greater and longer-term success of the diesel engine, today hot-bulb engines are sometimes called 'semi-diesels' or 'semi diesel' because they partly use compression-ignition in their cycle.

There is also a detail difference in the timing of the fuel injection process:

* In the hot-bulb engine, fuel is injected into the vapouriser during the Induction Stroke as air is drawn into the cylinder.

* In the diesel engine, fuel is injected into the cylinder in the final stages of the Compression Stroke.

However, Diesel's original engine design used compressed air to blast the fuel into the cylinder. This complex and heavy system limited the speed the engine could run at and the minimum size a diesel engine could be built to. This was needed to inject fuel under sufficient pressure for it to enter the highly compressed air in the cylinder. In hot-bulb engines fuel is injected before compression takes place, allowing a lighter, more accurate injection system to be used. Only when Akroyd-Stuart's mechanical pump-and-injector system that he developed for his hot-bulb engine was adapted by Robert Bosch for use in diesel engines (by making the system run at a much higher pressure) were high-speed diesel engines practical.

Uniflow steam engine

The uniflow type of steam engine uses steam that flows in one direction only in each half of the cylinder. Thermal efficiency is increased in the compound and multiple expansion types of steam engine by separating expansion into steps in separate cylinders; in the uniflow design, thermal efficiency is achieved by having a temperature gradient along the cylinder. Steam always enters at the hot ends of the cylinder and exhausts through ports at the cooler centre. By this means the relative heating and cooling of the cylinder walls is reduced.


Design details

Steam entry is usually controlled by poppet valves (which act similarly to those used in internal combustion engines) that are operated by a camshaft. The inlet valves open to admit steam when minimum expansion volume has been reached at the start of the stroke. For a period of the crank cycle steam is admitted and the poppet inlet is then closed, allowing continued expansion of the steam during the stroke, driving the piston. Near the end of the stroke the piston will expose a ring of exhaust ports mounted radially around the centre of the cylinder. These ports are connected by a manifold and piping to the condenser, lowering the pressure in the chamber to below that of the atmosphere causing rapid exhausting. Continued rotation of the crank moves the piston. From the animation the features of a uniflow engine can be seen, with a large piston almost half the length of the cylinder, poppet inlet valves at either end, a camshaft (whose motion is derived from that of the driveshaft) and a central ring of exhaust ports.


Advantages

Uniflow engines potentially allow greater expansion in a single cylinder without the relatively cool exhaust steam flowing across the hot end of the working cylinder and steam ports of a conventional "counterflow" steam engine during the exhaust stroke. This condition allows high thermal efficiency. The exhaust ports are only open for a small fraction of the piston stroke, therefore not all of the expanded steam is able to exhaust. This remaining steam is compressed by the returning piston and is thermodynamically desirable as it preheated the hot end of the cylinder before the admission of steam. However, the risk of excessive compression often resulted in small auxiliary exhaust ports being included at the cylinder heads. Such a design is called a semi-uniflow engine.

Engines of this type usually have multiple cylinders in an inline arrangement and may be single or double acting. A particular advantage of this type is that the valves may be operated by the effect of multiple camshafts, and by changing the relative phase of these camshafts, the amount of steam admitted may be increased for high torque at low speed and may be decreased at cruising speed for economy of operation, and by changing the absolute phase the engine's direction of rotation may be changed. The uniflow design also maintains a constant temperature gradient through the cylinder, avoiding passing hot and cold steam through the same end of the cylinder.



Disadvantages

In practice the uniflow engine has a number of operational shortcomings. The large expansion ratio requires a large cylinder volume. To gain the maximum potential work from this a high reciprocation rate was required, typically 80% faster than a double-acting engine. This caused the opening times of the inlet valves to be very short, putting great strain on a delicate mechanical part. In order to withstand the huge mechanical forces encountered, engines had to be heavily built and a large flywheel was required to smooth out the variations in torque as the steam pressure rapidly rose and fell in the cylinder. Additionally, as there was a thermal gradient across the cylinder, the metal of the wall expanded to different extents. This required precise boring of the cylinder barrel to be wider in the cool centre than at the hot ends. If the cylinder was not heated correctly, or if water entered, the delicate balance could be upset causing seizure mid-stroke or, potentially, destruction.



History

The uniflow engine was first used in Britain in 1827 by Jacob Perkins and was patented in 1885 by Leaonard Jennett Todd. It was popularised by German engineer Johann Stumpf in 1909, with the first commercial stationary engine produced a year previously in 1908.

The uniflow principle was mainly used for in industrial power generation, but was also tried in a few railway locomotives in England, such as The NER Uniflow Locomotive No 825 of 1913, The NER Uniflow Locomotive No 2212 of 1919, and The Midland Railway Paget locomotive. Experiments were also made in the USA and Russia. In no case were the results encouraging enough for further development to be undertaken.

The final commercial evolution of the Uniflow engine occurred in the USA during the late 1930s and 1940s by the Skinner Engine Company with the development of the Compound Unaflow Marine Steam Engine. This engine operated in a steeple compound configuration and provided efficiencies approaching contemporary diesels. Many bulk carriers and ferries on the Great Lakes were so equipped, several of which are still operating.

In small sizes (less than about 1000 horsepower ), reciprocating steam engines are much more efficient than steam turbines. The Whitecliffs solar steam power plant uses a three cylinder uniflow engine to generate about 25 kW electric output.

The Gerotor

A Gerotor is a positive displacement pumping unit. The name gerotor is derived from "Generated Rotor". A Gerotor unit consists of an inner and outer rotor. The inner rotor has N teeth, and the outer rotor has N+1 teeth. One rotor is located off-center and both rotors rotate. During part of the assembly's rotation cycle, the area between the inner and outer rotor increases, creating a vacuum. This vacuum creates suction, and hence, this part of the cycle is where the intake is located. Then, the area between the rotors decreases, causing compression. During this compression period, fluids can be pumped, or compressed (if they are gasseous fluids).

A gerotor can also function as a motor. High pressure gas enters the intake area and pushes against the inner and outer rotors, causing both to rotate as the area between the inner and outer rotor increases. During the compression period, the exhaust is pumped out. This is an Otto cycle engine.

An engine created by the Starrotor Corporation combines both uses of a gerotor. It uses the Brayton cycle, the same thermodynamic cycle employed by jet engines. A first gerotor compresses gas, this gas is then ignited in a combustor. The gaseous products of this combustion have a much higher pressure, which drives a second gerotor. Then, some of the output of the second gerotor is used to drive the 1st.

Capacitor discharge ignition

Capacitor discharge ignition (CDI) is a type of automotive electronic ignition system which is widely used in motorcycles, lawn mowers, chain saws, small engines and recently in some cars. Capacitor discharge ignition uses capacitor discharge current output to fire the spark plugs.


The basic principle

Most of typical ignition system used in cars are inductive ignition system, which is solely relying on the electric inductance at the coil to produce high-voltage electricity to the spark plugs. In a CDI system, the system charges a capacitor by default, and during the ignition point the system stopps charging the capacitor, allowing the capacitor to discharge its output to the final coil before reaching the spark plug.

A typical CDI module may consist of a small transformer, a charging circuit, a triggering circuit and a main capacitor. Firstly, the system voltage is raised up to 400 V by a transformer inside the CDI module. Then, the electric current flows to the charging circuit and charges the capacitor. The rectifier inside the charging circuit prevents capacitor discharge before the ignition point.

When the triggering circuit receives triggering signals from triggering devices such as Hall effect sensor or pulse generator during the ignition point, the triggering circuit stops the operation of the charging circuit, allowing the capacitor to discharge its output rapidly to the ignition coil. The rapid capacitor discharge then produces a very high voltage at about 40 kV to be fired at the spark plug. When there's no triggering signal, the charging circuit is re-connected to charge back the capacitor.


CDI modules can be generally divided into two:-

* AC-CDI - The AC-CDI module obtains its electricity source solely from the alternating current produced by the alternator. The AC-CDI system is the most basic CDI system which is widely used in small engines.
* DC-CDI - The DC-CDI module is powered by the battery, and therefore an additional DC/DC inverter circuit is included in the CDI module to raise the 12 V DC to 400 V DC, making the CDI module slightly larger. However, the vehicle that uses DC-CDI system has more precise ignition timing and the engine can be started easier when cold.


Advantages and Disadvantages of CDI

CDI system produces higher ignition voltage (about 40 kV) compared with typical inductive ignition system (about 20 kV). The higher voltage produced by the CDI system produces a hotter spark, enabling the engine to be operated even with badly-fouled spark plugs.

The CDI system also has a faster voltage rise time (between 3 ~ 10 kV/μs) compared with typical inductive systems (300 ~ 500 V/μs). The higher voltage rise time results in a shorter spark duration with the CDI system (10 ~ 12 μs) and therefore the spark output is more accurate.

However, the shorter spark duration means the CDI system is not suitable for sharing between cylinders in multi-cylinder engines. It was not until the end of the 1990s that CDI system could be practically used in multi-cylinder engines, especially in cars, as a result of the development of the direct ignition system, where each cylinder has its own ignition coil.

CDI systems also have problems with lean air-fuel mixture and high compression engines as well as cold-starting problems. However, the problems can be solved by using waste-spark methods.


History

THe history of capacitor discharge ignition system can be traced back in 1950s together with the development of other electronic ignition systems. The first commercial motorcycle using the CDI system was manufactured by Kawasaki.

By the end of 1960s, the US government made new laws enforcing strict emission standards. As a result, more and more electronic ignition systems were developed, and starting from 1970s all smaller engines installed CDI system to replace the contact point system, including Honda Cub which began to use AC-CDI system.

By the end of 1990s, direct ignition system using capacitor discharge ignition system was developed and started to be installed on some newer car models.

Ioe engine

The intake over exhaust (IOE) engine, also known as F-head and pocket valve, is a Four-stroke internal combustion engine of primitive design used in early Harley-Davidson motorcycles. The design was also used in other motorcycles, and in car engines by various manufacturers.

The intake valves are "overhead" (located in the cylinder head) and operated by rocker arms and pushrods from the camshaft in the crankcase, while the exhaust valves are flathead (located in the cylinder or engine block) and operated by the camshaft without pushrods or rocker arms. This was a low compression design.

The ioe design allowed the use of much larger valves than a side valve or overhead valve engine, and was still being used in four wheel drive vehicles in the 1960s. (eg CJ-3B Jeep 1953-1964, 1966 Land Rover Six.)

Cold air intake

A cold air intake is a system used to bring down the temperature of the air going into a car for the purpose of increasing the power of the internal-combustion engine. A secondary goal is to increase the appeal of a car by changing the appearance of a car's engine bay and creating an attractive intake noise. These aftermarket parts come in many different colors and many different sizes, and are an inexpensive way to increase performance.



History

The aftermarket company K&N Engineering first offered air intake systems in the late 1980s. Those intakes consisted of rotationally-molded plastic intake tubes and a conical, cotton gauze air filter. In the late 1990s a proliferation of intake manufacturers such as Injen, AEM, Airaid and Volant entered the fray. In addition, oversea manufacturers imported their designs lending to the popularity of Japan domestic market (JDM) air intakes in sport compact markets. K&N and many of the other intake companies now offer intake systems in metal tube designs, allowing a greater degree of customization (the tubes can be powder-coated or painted to match a vehicle).


Mechanics

All cold air intakes operate on the principle of increasing the amount of oxygen available for combustion with fuel. Because cooler air has more density for a given volume, cold air intakes generally work by introducing cooler air from outside the hot engine bay. However, the term "cold air intake" is often used to describe other methods of increasing oxygen to an engine, which may even increase the temperature of the air coming into an engine.

Some strategies used in designing cold-air intakes are:

* increasing the diameter of the air intake, allowing increased airflow.
* smoothing the interior of the intake to reduce air resistance.
* providing a more direct route to the air intake.
* tuning the length of the intake to provide maximum airflow at certain engine speeds (RPM).
* using a more efficient, less restricting air filter.


Application

Intake systems come in many different styles and can be constructed from plastic, metal, rubber (silicone) or composite materials (fiberglass, carbon fiber or kevlar). Due to the limited time air actually remains inside the intake tubing, the materials often do not impact a kit's ability to deliver cool air.

The most basic cold air intake replaces the stock airbox with a short metal or plastic tube leading to a conical air filter, called a Short ram air intake. The power gained by this method can vary depending on how restrictive the factory airbox is. The placement of the filter is usually directly in the engine compartment. The overall benefits depend on the specific application. Power may be lost at certain engine speeds, and gained at others. Because of the increased airflow and reduced covering, intake noise is usually increased. This effect is usually amplified on applications where a resonator, a part intended to reduce intake noise on some vehicles, is replaced by the intake.

Well designed intakes use heat shields to isolate the air filter from the rest of the engine compartment, providing cooler air from the front or side of the engine bay. Carbon fiber can be used for the piping instead of metal, reducing weight and insulating the air from the engine bay in some cases. Carbon fiber and other advanced composites (such as Kevlar) are expensive, and can be more aesthetic rather than functional.

The most extreme designs, sometimes referred to as Complete Cold Air (CCA) intakes, route air from outside the engine bay, usually from the wheel wells (although an extremely poor choice, as the air pressure is low), front grill (high air pressure), or a hood scoop (moderate air pressure). The intake can be placed such that the forward motion of the car pressurises the air coming in, creating a ram-air intake. These intakes often require additional modifications and can require body modifications or replacement panels, such as a replacement "ram air-style" hood. Complete Cold Air intakes can convert to short ram intakes for winter or wet driving.

When using a cold air intake, there is a potential risk when driving in the rain. This is often referred to as "hydrolock", and according to the automotive portal, MODsearch: "Say it's raining cats and dogs and you're out for a spin in your car. Normally you'd love to rip through puddles without thinking twice, but because your engine is now getting air from inside your bumper you have to be careful. If your engine manages to suck up any amount of water through the intake and into the engine you will probably have little to no horsepower left. In more extreme cases, the water brought into the engine through the intake can actually break connecting rods in the pistons, as water will not compress at all, unlike air. In other words, be careful." So, it is important to take the necessary precautions when using a cold air intake so you do not end up getting water in your engine. This may include installing a water shield in your intake or not driving in the rain at all. It is also notable that less damage will occur from water reaching the engine on a rotary engine car, as opposed to a piston engine car. Some cold air intake manufacturers now include a built in hydro-shield, a piece of plastic that blocks water from entering the air filter.

Air bypass valves are gaining popularity in cold air intake manufacturing. An air bypass valve is an open filtered spacer that is positioned more into the engine bay, between two connected pieces of the cold air intake assembly. This prevents hydro-locking by providing an alternate route for air to come in, thus eliminating the vacuum that causes water to be sucked in from a puddle. It is argued that this reduces power, but in actuality it provides more surface area for air enter the engine when the driver presses the pedal. When driving at moderate speeds, the suction caused by the engine is not enough to activate the air bypass valve.

GDi History

Contrary to what is generally written, Mercedes was not the first company to use fuel injection, or direct injection, on a production gasoline powered car. Both the 1952 Goliath GP700, and Gotbrud Superior 600, used Bosch direct fuel injection. The 1955 Mercedes-Benz 300SL, the first sports car to use fuel injection, used direct injection. The Bosch fuel injectors were placed into the bores on the cylinder wall used by the spark plugs in other Mercedes-Benz six-cylinder engines (the spark plugs were relocated to the cylinder head). Later, more mainstream applications of fuel injection favoured less expensive indirect injection methods.

It was not until 1996 that gasoline direct injection reappeared on the market. Mitsubishi Motors was the first with a GDI engine in the Japanese market Galant/Legnum's 4G93 1.8 L straight-4, which it subsequently brought to Europe in 1997 in the Mitsubishi Carisma, although Europe's high-sulphur fuel led to emissions problems, and fuel efficiency was less than expected. It also developed the first six cylinder GDI powerplant, the 6G74 3.5 L V6, in 1997. Mitsubishi applied this technology widely, producing over one million GDI engines in four families by 2001, PSA Peugeot Citroën and Hyundai Motors both licensed Mitsubishi's GDI technology in 1999, the latter using the first GDI V8. DaimlerChrysler produced a special engine for 2000, offered only in markets with low sulphur fuel.

Although other companies have since developed gasoline direct injection engines, GDI (with a capitalised letter "I") remains a registered trademark of Mitsubishi Motors.

Later GDi engines have been tuned and marketed for their high performance. Volkswagen/Audi led the trend with their 2001 GDi engine, under the product name Fuel Stratified Injection (FSI). The technology, adapted from Audi's Le Mans racecars.

BMW followed with a GDi V12. This initial BMW system used low-pressure injectors and could not enter lean-burn mode, but the company introduced its second-generation High Precision Injection system on the updated N52 straight-6 in 2006. This system surpasses many others with a wider envelope of lean-burn time, increasing overall efficiency. PSA is cooperating with BMW on a new line of engines which will make its first appearance in the 2007 MINI Cooper S.

General Motors had planned to produce a full range of GDi engines by 2002, but so far only two such engines have been introduced — in 2004, a version of the 2.2 L Ecotec used by the Opel Vectra and in 2005, a 2.0 L Ecotec with VVT technology for the Pontiac Solstice GXP.

In 2004 Isuzu Motors produced the first GDi engine sold in a mainstream American vehicle. Standard on the 2004 Axiom and optional on the 2004 Rodeo. Isuzu claimed the benefit of GDi is that the vaporizing fuel has a cooling effect, allowing a higher compression ratio (10.3 to 1 versus 9.1 to 1) that boosts output by 20 horsepower and that 0-to-60 times drop from 8.9 to just 7.5 seconds, with the quarter-mile being cut from 16.5 seconds to 15.8 ticks.

Toyota's 2GR-FSE V6 will use a combination of direct and indirect injection in 2006. It uses two injectors per cylinder, a traditional port injector and a new direct injector.

Mazda uses their own version of direct injection in the Mazdaspeed 6 / Mazda 6 MPS, the CX-7 sport-ute, and the new Mazdaspeed 3. It is referred to as Direct Injection Spark Ignition.

EnviroFit, a non-profit corporation sponsored by Colorado State University, has developed direct injection retrofit kits for heavily polluting two-stroke motorcycles in a project to reduce sometimes deadly air pollution in Southeast Asia. The kits use a technology invented and developed by Orbital Corporation Limited of Australia. Orbital's technology injects a mixture of fuel and compressed air into the combustion chamber instead of injecting fuel only, the most common system in automobiles. The compressed mixture rapidly expands as it enters the combustion chamber, and this breaks up the fuel into very small droplets which are more completely and efficiently burned, compared to carburetor and other fuel systems. The Orbital Combustion Process reduces two-stroke fuel consumption by 35 percent, according to EnviroFit. The organization, composed mostly of present and former CSU students and staff, has begun installing the kits on the millions of two-stroke taxis (motorcycles with big sidecars) in The Philippines. EnviroFit says its OCP kits reduce carbon monoxide emissions by 76 percent, carbon dioxide by 26 percent, and hydrocarbon emissions by 89 percent. Orbital's OCP two-stroke system is used in Mercury's Optimax DFI outboard engines, in Tohatsu's TLDI DFI outboard engines, in Bombardier's SeaDoo personal watercraft, and in motorscooters manufactured by Aprilia, Piaggio, Peugeot, and Kymco. Research on using the OCP system in four-stroke engines is underway.