Air-cooled engines rely on the circulation of air directly over hot parts of the engine to cool them. Most modern internal combustion engines are cooled by a closed circuit carrying liquid coolant through channels in the engine block and cylinder head, where the coolant absorbs heat, to a heat exchanger or radiator where the coolant releases heat into the air. Thus, while they are not cooled by the liquid, because of the liquid-coolant circuit they are known as water-cooled. In contrast, heat generated by an air-cooled engine is released directly into the air; this is facilitated with metal fins covering the outside of the Cylinder Head and cylinders which increase the surface area that air can act on. Air may be force fed with the use of a fan and shroud to achieve efficient cooling with high volumes of air or by natural air flow with well designed and angled fins. In all combustion engines, a great percentage of the heat generated escapes through the exhaust, not through either a liquid cooling system nor through the metal fins of an air-cooled engine.
About 8% of the heat energy finds its way into the oil, which although meant for lubrication plays a role in heat dissipation via a cooler. Many motorcycles use air cooling for the sake of reducing complexity. Few current production automobiles have air-cooled engines, but it was common for many high-volume vehicles. Examples of past air-cooled road vehicles, in chronological order, include: Franklin New Way - limited production run out from the "CLARKMOBILE" GM "copper-cooled" models of Chevrolet and Oakland Tatra all-wheel-drive military trucks. Tatra 11 and subsequent models Tatra T77 Tatra T87 Tatra T97 Tatra T600 Tatraplan Tatra T603 Tatra T613 Tatra T700 Crosley The East German Trabant Trabant 500 Trabant 600 Trabant 601 ZAZ Zaporozhets Fiat 500 Fiat 126 Porsche 356 VW-Porsche 914 Porsche 911 The Volkswagen Beetle, Type 2, SP2, Karmann Ghia, Type 3 all utilized the same air-cooled engine with various displacements. Volkswagen Type 2. Volkswagen Type 4 Volkswagen Gol Chevrolet Corvair Citroën 2CV.
Citroën GS and GSA Honda 1300 NSU Prinz Royal Enfield Motorcycles: The 350cc and 500cc Twinspark motorcycle engines are air-cooled Oltcit_Club T13/653, G11/631 and VO36/630 Most aviation piston engines are air-cooled. While water cooled engines were used from the early days of flight, air cooled engines were the dominant choice in aircraft. Following the Second World War and jet turbine powered aircraft have come to dominate flight regimes where water cooled piston engines offered the advantage of reduced drag. Today, piston engines are used in slower general aviation aircraft where the greater drag produced by air cooled engines is not a major disadvantage. Therefore, most aero engines produced. Today, most of the engines manufactured by Lycoming and Continental and used by major manufacturers of light aircraft Cirrus, Cessna and so on. Other engine manufactures using air-cooled engine technology are ULPower and Jabiru, more active in the Light-Sport Aircraft and ultralight aircraft market.
Rotax uses a combination of liquid-cooled cylinder heads. Some small diesel engines, e.g. those made by Lister Petter are air-cooled. The only big Euro 5 truck air-cooled engine is being produced by Tatra. Stationary or portable engines were commercially introduced early in the 1900s; the first commercial production was by the New Way Motor Company of Lansing, Michigan, US. The company produced air-cooled engines in single and twin cylinders in both horizontal and vertical cylinder format. Subsequent to their initial production, exported worldwide, other companies took up the advantages of this cooling method in small portable engines. Applications include mowers, outboard motors, pump sets, saw benches and auxiliary power plants and more. Sloan, Alfred P. McDonald, John, ed. My Years with General Motors, Garden City, NY, USA: Doubleday, LCCN 64011306, OCLC 802024. Republished in 1990 with a new introduction by Peter Drucker. Biermann, A. E.. "The design of fins for air-cooled cylinders". Report Nº 726.
NACA. P V Lamarque, "The design of cooling fins for Motor-Cycle Engines". Report of the Automobile Research Committee, Institution of Automobile Engineers Magazine, March 1943 issue, in "The Institution of Automobile Engineers. Proceedings XXXVII, Session 1942-1943, pp 99-134 and 309-312. Julius Mackerle, "Air-cooled Automotive Engines", Charles Griffin & Company Ltd. London 1972
In both road and rail vehicles, the wheelbase is the distance between the centers of the front and rear wheels. For road vehicles with more than two axles, the wheelbase is the distance between the steering axle and the centerpoint of the driving axle group. In the case of a tri-axle truck, the wheelbase would be the distance between the steering axle and a point midway between the two rear axles; the wheelbase of a vehicle equals the distance between its rear wheels. At equilibrium, the total torque of the forces acting on a vehicle is zero. Therefore, the wheelbase is related to the force on each pair of tires by the following formula: F f = d r L m g F r = d f L m g where F f is the force on the front tires, F r is the force on the rear tires, L is the wheelbase, d r is the distance from the center of mass to the rear wheels, d f is the distance from the center of gravity to the front wheels, m is the mass of the vehicle, g is the gravity constant. So, for example, when a truck is loaded, its center of gravity shifts rearward and the force on the rear tires increases.
The vehicle will ride lower. The amount the vehicle sinks will depend on counter acting forces, like the size of the tires, tire pressure, the spring rate of the suspension. If the vehicle is accelerating or decelerating, extra torque is placed on the rear or front tire respectively; the equation relating the wheelbase, height above the ground of the CM, the force on each pair of tires becomes: F f = d r L m g − h c m L m a F r = d f L m g + h c m L m a where F f is the force on the front tires, F r is the force on the rear tires, d r is the distance from the CM to the rear wheels, d f is the distance from the CM to the front wheels, L is the wheelbase, m is the mass of the vehicle, g is the acceleration of gravity, h c m is the height of the CM above the ground, a is the acceleration. So, as is common experience, when the vehicle accelerates, the rear sinks and the front rises depending on the suspension; when braking the front noses down and the rear rises.:Because of the effect the wheelbase has on the weight distribution of the vehicle, wheelbase dimensions are crucial to the balance and steering.
For example, a car with a much greater weight load on the rear tends to understeer due to the lack of the load on the front tires and therefore the grip from them. This is why it is crucial, when towing a single-axle caravan, to distribute the caravan's weight so that down-thrust on the tow-hook is about 100 pounds force. A car may oversteer or "spin out" if there is too much force on the front tires and not enough on the rear tires; when turning there is lateral torque placed upon the tires which imparts a turning force that depends upon the length of the tire distances from the CM. Thus, in a car with a short wheelbase, the short lever arm from the CM to the rear wheel will result in a greater lateral force on the rear tire which means greater acceleration and less time for the driver to adjust and prevent a spin out or worse. Wheelbases provide the basis for one of the most common vehicle size class systems; some luxury vehicles are offered with long-wheelbase variants to increase the spaciousness and therefore the luxury of the vehicle.
This practice can be found on full-size cars like the Mercedes-Benz S-Class, but ultra-luxury vehicles such as the Rolls-Royce Phantom and large family cars like the Rover 75 came with'limousine' versions. Prime Minister of the United Kingdom Tony Blair was given a long-wheelbase version of the Rover 75 for official use, and some SUVs like the VW Tiguan and Jeep Wrangler come in LWB models In contrast, coupé varieties of some vehicles such as the Honda Accord are built on shorter wheelbases than the sedans they are derived from. The wheelbase on many commercially available bicycles and motorcycles is so short, relative to the height of their centers of mass, that they are able to perform stoppies and wheelies. In skateboarding the word'wheelbase' is used for the distance between the two inner pairs of mounting holes on the deck; this is different from the distance between the rotational centers
Portugal the Portuguese Republic, is a country located on the Iberian Peninsula in southwestern Europe. It is the westernmost sovereign state of mainland Europe, being bordered to the west and south by the Atlantic Ocean and to the north and east by Spain, its territory includes the Atlantic archipelagos of the Azores and Madeira, both autonomous regions with their own regional governments. Portugal is the oldest state on the Iberian Peninsula and one of the oldest in Europe, its territory having been continuously settled and fought over since prehistoric times; the pre-Celtic people, Celts and Romans were followed by the invasions of the Visigoths and Suebi Germanic peoples. Portugal as a country was established during the Christian Reconquista against the Moors who had invaded the Iberian Peninsula in 711 AD. Founded in 868, the County of Portugal gained prominence after the Battle of São Mamede in 1128; the Kingdom of Portugal was proclaimed following the Battle of Ourique in 1139, independence from León was recognised by the Treaty of Zamora in 1143.
In the 15th and 16th centuries, Portugal established the first global empire, becoming one of the world's major economic and military powers. During this period, today referred to as the Age of Discovery, Portuguese explorers pioneered maritime exploration, notably under royal patronage of Prince Henry the Navigator and King John II, with such notable voyages as Bartolomeu Dias' sailing beyond the Cape of Good Hope, Vasco da Gama's discovery of the sea route to India and the European discovery of Brazil. During this time Portugal monopolized the spice trade, divided the world into hemispheres of dominion with Castille, the empire expanded with military campaigns in Asia. However, events such as the 1755 Lisbon earthquake, the country's occupation during the Napoleonic Wars, the independence of Brazil, a late industrialization compared to other European powers, erased to a great extent Portugal's prior opulence. After the 1910 revolution deposed the monarchy, the democratic but unstable Portuguese First Republic was established being superseded by the Estado Novo right-wing authoritarian regime.
Democracy was restored after the Carnation Revolution in 1974. Shortly after, independence was granted to all its overseas territories; the handover of Macau to China in 1999 marked the end of what can be considered the longest-lived colonial empire. Portugal has left a profound cultural and architectural influence across the globe, a legacy of around 250 million Portuguese speakers, many Portuguese-based creoles, it is a developed country with a high-income advanced economy and high living standards. Additionally, it is placed in rankings of moral freedom, democracy, press freedom, social progress, LGBT rights. A member of the United Nations and the European Union, Portugal was one of the founding members of NATO, the eurozone, the OECD, the Community of Portuguese Language Countries; the word Portugal derives from the Roman-Celtic place name Portus Cale. Portus, the Latin word for port or harbour, Cala or Cailleach was the name of a Celtic goddess – in Scotland she is known as Beira – and the name of an early settlement located at the mouth of the Douro River which flows into the Atlantic Ocean in the north of what is now Portugal.
At the time the land of a specific people was named after its deity. Those names are the origins of the - gal in Galicia. Incidentally, the meaning of Cale or Calle is a derivation of the Celtic word for port which would confirm old links to pre-Roman, Celtic languages which compare to today's Irish caladh or Scottish cala, both meaning port; some French scholars believe it may have come from ` Portus Gallus', the port of the Celts. Around 200 BC, the Romans took the Iberian Peninsula from the Carthaginians during the Second Punic War, in the process conquered Cale and renamed it Portus Cale incorporating it to the province of Gaellicia with capital in Bracara Augusta. During the Middle Ages, the region around Portus Cale became known by the Suebi and Visigoths as Portucale; the name Portucale evolved into Portugale during the 7th and 8th centuries, by the 9th century, that term was used extensively to refer to the region between the rivers Douro and Minho. By the 11th and 12th centuries, Portugallia or Portvgalliae was referred to as Portugal.
The early history of Portugal is shared with the rest of the Iberian Peninsula located in South Western Europe. The name of Portugal derives from the joined Romano-Celtic name Portus Cale; the region was settled by Pre-Celts and Celts, giving origin to peoples like the Gallaeci, Lusitanians and Cynetes, visited by Phoenicians, Ancient Greeks and Carthaginians, incorporated in the Roman Republic dominions as Lusitania and part of Gallaecia, after 45 BC until 298 AD. The region of present-day Portugal was inhabited by Neanderthals and by Homo sapiens, who roamed the border-less region of the northern Iberian peninsula; these were subsistence societies that, although they did not establish prosperous settlements, did form organized societies. Neolithic Portugal experimented with domestication of herding animals, the raising of some cereal crops and fluvial or marine fishing, it is believed by some scholars that early in the first millennium BC, several waves of Celts invaded Portugal from Central Europe and inter-married with the local populations, forming differe
Socialist Federal Republic of Yugoslavia
The Socialist Federal Republic of Yugoslavia was a country located in central and Southeastern Europe that existed from its foundation in the aftermath of World War II until its dissolution in 1992 amid the Yugoslav Wars. Covering an area of 255,804 km², the SFRY was bordered by the Adriatic Sea and Italy to the west and Hungary to the north and Romania to the east, Albania and Greece to the south; the nation was a socialist state and a federation governed by the League of Communists of Yugoslavia and made up of six socialist republics: Bosnia and Herzegovina, Macedonia, Montenegro and Slovenia with Belgrade as its capital. In addition, it included two autonomous provinces within Serbia: Vojvodina; the SFRY's origin is traced to 26 November 1942, when the Anti-Fascist Council for the National Liberation of Yugoslavia was formed during World War II. On 29 November 1945, the Federal People's Republic of Yugoslavia was proclaimed after the deposition of King Peter II, thus ending the monarchy.
Until 1948, the new communist government sided with the Eastern Bloc under the leadership of Josip Broz Tito at the beginning of the Cold War, but after the Tito–Stalin split of 1948, Yugoslavia pursued a policy of neutrality. It became one of the founding members of the Non-Aligned Movement, transitioned from a planned economy to market socialism; the SFRY maintained neutrality during the Cold War as part of its foreign policy. It was a founding member of CERN, the United Nations, Non-Aligned Movement, OSCE, IFAD, WTO, BTWC. Following the death of Tito on 4 May 1980, the Yugoslav economy started to collapse, which increased unemployment and inflation; the economic crisis led to a rise in ethnic nationalism in early 1990s. With the collapse of communism in Eastern Europe, inter-republic talks on transformation of the federation failed. In 1991 some European states recognized their independence; the federation collapsed along federal borders, followed by the start of the Yugoslav Wars, the final downfall and breakup of the federation on 27 April 1992.
Two of its republics and Montenegro, remained within a reconstituted state known as the "Federal Republic of Yugoslavia", but this union was not recognized internationally as the official successor state to the SFRY. The term "former Yugoslavia" is now used retrospectively; the name Yugoslavia, an Anglicised transcription of Jugoslavija, is a composite word made up of jug and slavija. The Slavic word jug means'south', while slavija denotes a'land of the Slavs'. Thus, a translation of Jugoslavija would be'South-Slavia' or'Land of the South Slavs'; the full official name of the federation varied between 1945 and 1992. Yugoslavia was formed in 1918 under the name Kingdom of Serbs and Slovenes. In January 1929, King Alexander I assumed dictatorship of the kingdom and renamed it the Kingdom of Yugoslavia, for the first time making the term "Yugoslavia"—which had been used colloquially for decades —the official name of the state. After the Kingdom was occupied by the Axis during World War II, the Anti-Fascist Council for the National Liberation of Yugoslavia announced in 1943 the formation of the Democratic Federal Yugoslavia in the substantial resistance-controlled areas of the country.
The name deliberately left the republic-or-kingdom question open. In 1945, King Peter II was deposed, with the state reorganized as a republic, accordingly renamed Federal People's Republic of Yugoslavia, with the constitution coming into force in 1946. In 1963, amid pervasive liberal constitutional reforms, the name Socialist Federal Republic of Yugoslavia was introduced; the state is most referred to by the latter name, which it held for the longest period of all. Of the three main Yugoslav languages, the Serbo-Croatian and Macedonian language name for the state was identical, while Slovene differed in capitalization and the spelling of the adjective "Socialist"; the names are as follows: Serbo-Croatian and Macedonian languages Latin: Socijalistička Federativna Republika Jugoslavija Cyrillic: Социјалистичка Федеративна Република Југославија Serbo-Croatian pronunciation: Macedonian pronunciation: Slovene language Socialistična federativna republika Jugoslavija Due to the length of the name, abbreviations were used to refer to the Socialist Federal Republic of Yugoslavia, though the state was most known as Yugoslavia.
The most common abbreviation is SFRY, though SFR Yugoslavia was used in an official capacity by the media. On 6 April 1941, Yugoslavia was invaded by the Axis powers led by Nazi Germany. Yugoslav resistance was soon established in two forms, the Royal Yugoslav Army in the Homeland and the Communist Yugoslav Partisans; the Partisan supreme commander was Josip Broz Tito, under his command the movement soon began establishing "liberated territories" which attracted the attention of occupying forces. Unlike the various nationalist militias operating in occupied Yugoslavia, the Partisans were a pan-Yugoslav movement promoting the "brotherhood and unity" of Yugoslav nations, representing the republican, left-wing, socialist elements of the Yugoslav political
Citroën is a French automobile manufacturer, part of the PSA Peugeot Citroën group since 1976, founded in 1919 by French industrialist André-Gustave Citroën. In 1934, the firm established its reputation for innovative technology with the Traction Avant; this car was the world's first mass-produced front wheel drive car, one of the first to feature a unitary type body, with no chassis supporting the mechanical components. In 1954 they produced the world's first hydropneumatic self-levelling suspension system in 1955, the revolutionary DS, the first mass-produced car with modern disc brakes and, in 1967, they introduced in several of their models swiveling headlights that allowed for greater visibility on winding roads. With a successful history in motorsport, Citroën is the only automobile manufacturer to have won three different official championships from the International Automobile Federation: the World Rally Raid Championship five times, the World Rally Championship eight times and the World Touring Car Championship.
Citroën has been selling vehicles in China since 1984 via the Dongfeng Peugeot-Citroën joint venture, which today represents a major market for the brand. In 2014, when PSA Peugeot Citroën ran into severe financial difficulties, the Dongfeng Motor Corporation took an ownership stake. André Citroën built armaments for France during World War I. There was nothing automatic about his decision to become an automobile manufacturer once the war was over: the automotive business was one that Citroën knew well, thanks to a successful six-year stint working with Mors between 1908 and the outbreak of war; the decision to switch to automobile manufacturing was evidently taken as early as 1916, the year when Citroën asked the engineer Louis Dufresne with Panhard, to design a technically-sophisticated 18HP automobile for which he could use his factory once peace returned. Long before that happened, however, he had modified his vision and decided, like Henry Ford, that the best post-war opportunities in auto-making would involve a lighter car of good quality, but made in sufficient quantities to be priced enticingly.
In February 1917 Citroën contacted another engineer, Jules Salomon, who had a considerable reputation within the French automotive sector as the creator, in 1909, of a little car called Le Zèbre. André Citroën's mandate was characteristically demanding and characteristically simple: to produce an all-new design for a 10 HP car that would be better equipped, more robust and less costly to produce than any rival product at the time; the result was the Type A, announced to the press in March 1919, just four months after the guns fell silent. The first production Type A emerged from the factory at the end of May 1919 and in June it was exhibited at a show room at Number 42, on the Champs-Élysées in Paris which sold Alda cars. Citroën persuaded the owner of the Alda business, Fernand Charron, to lend him the show-room, still in use today; this C42 showroom is where the company organises exhibitions and shows its vehicles and concept cars. A few years Charron would be persuaded to become a major investor in the Citroën business.
On 7 July 1919, the first customer took delivery of a new Citroën 10HP Type A. That same year, André Citroën negotiated with General Motors a proposed sale of the Citroën company; the deal nearly closed, but General Motors decided that its management and capital would be too overstretched by the takeover. Thus Citroën remained independent till 1935. Between 1921 and 1937, Citroën produced half-track vehicles for off-road and military uses, using the Kégresse track system. In the 1920s, the U. S. Army purchased several Citroën-Kégresse vehicles for evaluation followed by a licence to produce them; this resulted in the Army Ordnance Department building a prototype in 1939. In December 1942, it went into production with the M2 Half Track M3 Half-track versions; the U. S. produced more than 41,000 vehicles in over 70 versions between 1940 and 1944. After their 1940 occupation of France, the Nazi's captured many of the Citroën half-track vehicles and armored them for their own use. Mr Citroën was a keen marketer: he used the Eiffel Tower as the world's largest advertising sign, as recorded in Guinness World Records.
He sponsored expeditions in Asia, North America and Africa, demonstrating the potential for motor vehicles equipped with the Kégresse track system to cross inhospitable regions. These expeditions conveyed journalists. Demonstrating extraordinary toughness, a 1923 Citroën that had travelled 48,000 km was the first car to be driven around Australia; the car, a 1923 Citroën 5CV Type C Torpedo, was driven by Neville Westwood from Perth, Western Australia, on a round trip from August to December 1925. This vehicle is now restored and in the collection of the National Museum of Australia. In 1924, Citroën began a business relationship with the American engineer Edward G. Budd. From 1899, Budd had worked to develop stainless steel bodies for railroad cars, for the Pullman in particular. Budd went on to manufacture steel bodies for many automakers. At the Paris Motor Show in October 1924, Citroën introduced the Citroën B10, the first all-steel body in Europe; these automobiles were successful in the marketplace, but soon competitors introduced new body des
An engine or motor is a machine designed to convert one form of energy into mechanical energy. Heat engines, like the internal combustion engine, burn a fuel to create heat, used to do work. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air, clockwork motors in wind-up toys use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and motion; the word engine derives from Old French engin, from the Latin ingenium–the root of the word ingenious. Pre-industrial weapons of war, such as catapults and battering rams, were called siege engines, knowledge of how to construct them was treated as a military secret; the word gin, as in cotton gin, is short for engine. Most mechanical devices invented during the industrial revolution were described as engines—the steam engine being a notable example. However, the original steam engines, such as those by Thomas Savery, were not mechanical engines but pumps.
In this manner, a fire engine in its original form was a water pump, with the engine being transported to the fire by horses. In modern usage, the term engine describes devices, like steam engines and internal combustion engines, that burn or otherwise consume fuel to perform mechanical work by exerting a torque or linear force. Devices converting heat energy into motion are referred to as engines. Examples of engines which exert a torque include the familiar automobile gasoline and diesel engines, as well as turboshafts. Examples of engines which produce thrust include rockets; when the internal combustion engine was invented, the term motor was used to distinguish it from the steam engine—which was in wide use at the time, powering locomotives and other vehicles such as steam rollers. The term motor derives from the Latin verb moto which means to maintain motion, thus a motor is a device. Motor and engine are interchangeable in standard English. In some engineering jargons, the two words have different meanings, in which engine is a device that burns or otherwise consumes fuel, changing its chemical composition, a motor is a device driven by electricity, air, or hydraulic pressure, which does not change the chemical composition of its energy source.
However, rocketry uses the term rocket motor though they consume fuel. A heat engine may serve as a prime mover—a component that transforms the flow or changes in pressure of a fluid into mechanical energy. An automobile powered by an internal combustion engine may make use of various motors and pumps, but all such devices derive their power from the engine. Another way of looking at it is that a motor receives power from an external source, converts it into mechanical energy, while an engine creates power from pressure. Simple machines, such as the club and oar, are prehistoric. More complex engines using human power, animal power, water power, wind power and steam power date back to antiquity. Human power was focused by the use of simple engines, such as the capstan, windlass or treadmill, with ropes and block and tackle arrangements; these were used in cranes and aboard ships in Ancient Greece, as well as in mines, water pumps and siege engines in Ancient Rome. The writers of those times, including Vitruvius and Pliny the Elder, treat these engines as commonplace, so their invention may be more ancient.
By the 1st century AD, cattle and horses were used in mills, driving machines similar to those powered by humans in earlier times. According to Strabo, a water powered mill was built in Kaberia of the kingdom of Mithridates during the 1st century BC. Use of water wheels in mills spread throughout the Roman Empire over the next few centuries; some were quite complex, with aqueducts and sluices to maintain and channel the water, along with systems of gears, or toothed-wheels made of wood and metal to regulate the speed of rotation. More sophisticated small devices, such as the Antikythera Mechanism used complex trains of gears and dials to act as calendars or predict astronomical events. In a poem by Ausonius in the 4th century AD, he mentions a stone-cutting saw powered by water. Hero of Alexandria is credited with many such wind and steam powered machines in the 1st century AD, including the Aeolipile and the vending machine these machines were associated with worship, such as animated altars and automated temple doors.
Medieval Muslim engineers employed gears in mills and water-raising machines, used dams as a source of water power to provide additional power to watermills and water-raising machines. In the medieval Islamic world, such advances made it possible to mechanize many industrial tasks carried out by manual labour. In 1206, al-Jazari employed a crank-conrod system for two of his water-raising machines. A rudimentary steam turbine device was described by Taqi al-Din in 1551 and by Giovanni Branca in 1629. In the 13th century, the solid rocket motor was invented in China. Driven by gunpowder, this simplest form of internal combustion engine was unable to deliver sustained power, but was useful for propelling weaponry at high speeds towards enemies in battle and for fireworks. After invention, this innovation spread throughout Europe; the Watt steam engine was the first type of steam engine to make use of steam at a pressure just above atmospheric to drive the piston he