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Teardrop Trailer (truck)
A teardrop trailer is an aerodynamically shaped semi-trailer with a curved-roof that differs in shape from the traditional rectangularly shaped trailer. The trailer is meant to be paired with a compatibly designed tractor unit leading to greater fuel efficiency of the tractor-trailer combination. As such, the "teardrop" phrase refers to the entire combination, not just the trailer. The curved shape of the roof decreases aerodynamic drag by smoothing airflow over the top, thus improving fuel efficiency. One operator has reported the trailers save 2% in fuel in service that included significant low speed delivery operation and 5% in higher speed long-haul operation. Another factor improving airflow is the gap between the tractor and trailer is minimized to lessen the amount of turbulence created by air flowing into the gap. Teardrop trailers are only available in the United Kingdom and manufactured by one company, Don-Bur Trailers & Bodies Ltd which has patented the design. The ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerodynamically
Aerodynamics () is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics. The term ''aerodynamics'' is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North American
North America is a continent in the Northern and Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the south and west by the Pacific Ocean. The region includes Middle America (comprising the Caribbean, Central America, and Mexico) and Northern America. North America covers an area of about , representing approximately 16.5% of Earth's land area and 4.8% of its total surface area. It is the third-largest continent by size after Asia and Africa, and the fourth-largest continent by population after Asia, Africa, and Europe. , North America's population was estimated as over 592 million people in 23 independent states, or about 7.5% of the world's population. In human geography, the terms "North America" and "North American" refers to Canada, Greenland, Mexico, Saint Pierre and Miquelon, and the United States. It is unknown with certainty how ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transportation Engineering
Transportation engineering or transport engineering is the application of technology and scientific principles to the planning, functional design, operation and management of facilities for any mode of transportation to provide for the safe, efficient, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods transport. Theory The planning aspects of transportation engineering relate to elements of urban planning, and involve technical forecasting decisions and political factors. Technical forecasting of passenger travel usually involves an urban transportation planning model, requiring the estimation of trip generation, trip distribution, mode choice, and route assignment. More sophisticated forecasting can include other aspects of traveler decisions, including auto ownership, trip chaining (the decision to link individual trips together in a tour) and the choice of residential or business location (known as land use forec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shipping And The Environment
Freight transport, also referred to as freight forwarding, is the physical process of transporting Commodity, commodities and merchandise goods and cargo. The term shipping originally referred to transport by sea but in American English, it has been extended to refer to transport by land or air (International English: "carriage") as well. "Logistics", a term borrowed from the military environment, is also used in the same sense. History Prehistoric Era Initial human civilization relied heavily on Domestication, domesticated animals, such as Horse, horses, Camel, camels, and Donkey, donkeys, to transport their goods. The invention of the wheel in Mesopotamia in 5000BC improved this efficiency by allowing for carts and carriages to be created, which animals could pull. Classical Era Romans The Roman Empire, Romans built a vast network of roads, which facilitated trade across the numerous cities in its empire. Silk Road Transport along the silk road, a land-based r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articulated Vehicles
An articulated vehicle is a vehicle which has a permanent or semi-permanent coupling in its construction. This coupling works as a large pivot joint, allowing it to bend and turn more sharply. There are many kinds, from heavy equipment to buses, trams and trains. Steam locomotives were sometimes articulated so the driving wheels could pivot around corners. In a broader sense, any vehicle towing a trailer (including a semi-trailer) could be described as articulated (which comes from the Latin word ''articulus'', "small joint"). In the UK, an ''articulated lorry'' is the combination of a tractor and a trailer, abbreviated to "artic". In the US, it is called a semi-trailer truck, tractor-trailer or semi-truck and is not necessarily considered articulated. Types Buses Buses are articulated to allow for a much longer bus that can still navigate within the turning radius of a normal bus. Most buses have one articulation, but some have two. Trucks In the UK, tractor unit an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Road Haulage
Haulage is the business of transporting goods by road or rail between suppliers and large consumer outlets, factories, warehouses, or depots. This includes everything humans might wish to move in bulk – from vegetables and other foodstuffs, to clothes, ore, coal, and other supplies. Haulage also involves the transportation of chemicals in large sealed containers, and the removal of waste. As the word implies, goods are loaded into large trailers or carriages and hauled between different locations. Traditionally, this was by large animals such as horses or oxen – where the practice may also be called cartage or drayage. However, in the modern age, this act is mostly performed by trains or trucks – with large shipping vessels acting as intermediaries for crossing oceans. Truck drivers on haulage shifts are typically male, and often work long and difficult hours with few breaks – regularly sleeping in their vehicles overnight and eating/showering at rest stops. It is expecte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-trailer Aerodynamic Device
Semi-trailer aerodynamic devices are devices affixed to semi-trailers, for the purpose of reducing aerodynamic drag caused by air turbulence. The two major types of device in use are trailer skirts (or side skirts), affixed to the underside of trailers, and trailer tails (or boat tails, or rear fairings), affixed to the rear. Several such devices have been recognized by the U.S. United States Environmental Protection Agency, Environmental Protection Agency's SmartWay Transport Partnership, making them eligible for funding under the Diesel Emissions Reduction Act. Trailer skirts Construction Trailer skirts comprise a pair of panels affixed to the lower side edges of a trailer, running most of the length of the trailer and filling the gap between the forward and rear axles. Trailer skirts are typically constructed of aluminum, plastic, or fiberglass, with plastic the most resistant to damage from side or bottom impacts. Skirts may have a modularity, modular design, allowing install ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germany
Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total population of over 84 million in an area of , making it the most populous member state of the European Union. It borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, and France, Luxembourg, Belgium, and the Netherlands to the west. The Capital of Germany, nation's capital and List of cities in Germany by population, most populous city is Berlin and its main financial centre is Frankfurt; the largest urban area is the Ruhr. Settlement in the territory of modern Germany began in the Lower Paleolithic, with various tribes inhabiting it from the Neolithic onward, chiefly the Celts. Various Germanic peoples, Germanic tribes have inhabited the northern parts of modern Germany since classical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlantic, North Atlantic, the French West Indies, and List of islands of France, many islands in Oceania and the Indian Ocean, giving it Exclusive economic zone of France, one of the largest discontiguous exclusive economic zones in the world. Metropolitan France shares borders with Belgium and Luxembourg to the north; Germany to the northeast; Switzerland to the east; Italy and Monaco to the southeast; Andorra and Spain to the south; and a maritime border with the United Kingdom to the northwest. Its metropolitan area extends from the Rhine to the Atlantic Ocean and from the Mediterranean Sea to the English Channel and the North Sea. Its Regions of France, eighteen integral regions—five of which are overseas—span a combined area of and hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deutsche Post DHL
Deutsche Post AG (), trade name, trading as DHL Group, is a German multinational corporation, multinational package delivery and supply chain management company headquartered in Bonn, Germany. It is one of the world's largest courier companies. The postal division, Deutsche Post, delivers 61 million letters each day in Germany, making it Europe's largest such company. The trade name's eponymous parcel division DHL is a wholly owned subsidiary claimed to be present in over 220 countries and territories. DHL Group was the largest logistics company worldwide in 2022. DHL Group is the successor to the German mail authority Deutsche Bundespost, the oldest modern postal service in the world, tracing its roots to the Kaiserliche Reichspost, middle ages. It was privatized in 1995 and became a fully independent company in 2000. Since its privatization, Deutsche Post has significantly expanded its business area through acquisitions. In late 2014, the group acquired StreetScooter GmbH, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rolling Resistance
Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the Motion (physics), motion when a body (such as a ball, tire, or wheel) Rolling, rolls on a surface. It is mainly caused by Plasticity (physics), non-elastic effects; that is, not all the energy needed for deformation (or movement) of the wheel, roadbed, etc., is recovered when the pressure is removed. Two forms of this are hysteresis losses (see rolling resistance#Primary cause, below), and permanent plastic deformation, (plastic) deformation of the object or the surface (e.g. soil). Note that the frictional contact mechanics, slippage between the wheel and the surface also results in energy dissipation. Although some researchers have included this term in rolling resistance, some suggest that this dissipation term should be treated separately from rolling resistance because it is due to the applied torque to the wheel and the resultant slip between the wheel and ground, which is called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rumpler Tropfenwagen
The Rumpler Tropfenwagen ("Rumpler drop car", named after its raindrop shape) was a car developed by Austrian engineer Edmund Rumpler. The Tropfenwagen Aerodynamics Rumpler, born in Vienna, was known as a designer of aircraft when at the 1921 Berlin car show he introduced the Tropfenwagen. It was to be the first ''streamlined'' production car, before the Chrysler Airflow and Tatra T77. The Rumpler was already wind tunnel optimized at the Aerodynamics Research Institute in Göttingen and had a Automobile drag coefficient, drag coefficient of only 0.28, a value that astonished later engineers when they tested the Tropfenwagen in the 1970s. This would be competitive even today. For comparison: the top ten most aerodynamic production cars in 2014/2015 were in the range 0.26 down to 0.19. The Fiat 508, Fiat ''Balilla'' of the mid-1930s, by contrast, was rated at 0.60. To enable the car's aerodynamic shape, the Tropfenwagen also featured the world's first (single plane) curved windows in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
