Henry Philibert Gaspard Darcy was a French engineer who made several important contributions to hydraulics including Darcy’s law for flow in porous media. Darcy was born in France. Despite his father's death in 1817 when he was 14, his mother was able to borrow money to pay for his tutors. In 1821 he enrolled at the École Polytechnique in Paris, transferred two years to the School of Bridges and Roads, which led to employment in the Corps of Bridges and Roads. Henry met an English woman, Henriette Carey, whose family had been living in Dijon, married her in 1828; as a member of the Corps, he built an impressive pressurized water distribution system in Dijon following the failure of attempts to supply adequate fresh water by drilling wells. The system carried water from Rosoir Spring 12.7 kilometres away through a covered aqueduct to reservoirs near the city, which fed into a network of 28,000 meters of pressurized pipes delivering water to much of the city. The system was closed and driven by gravity, thus required no pumps with just sand acting as a filter.
He was involved in many other public works in and around Dijon, as well as in the politics of the Dijon city government. During this period he modified the Prony equation for calculating head loss due to friction, which after further modification by Julius Weisbach would become the well-known Darcy–Weisbach equation still in use today. In 1848 he became Chief Engineer for the département. Soon thereafter he left Dijon due to political pressure, but was promoted to Chief Director for Water and Pavements and took up office in Paris. While in that position, he was able to focus more on his hydraulics research on flow and friction losses in pipes. During this period he improved the design of the Pitot tube, into the form used today, he resigned his post in 1855 due to poor health, but was permitted to continue his research in Dijon. In 1855 and 1856 he conducted column experiments that established what has become known as Darcy's law; the unit of measure of fluid permeability, the darcy is named in his honour.
Darcy died of pneumonia while on a trip to Paris in 1858, is buried in Cimetière de Dijon in Dijon. Les fontaines publiques de la ville de Dijon: exposition et application... Victor Dalmont. 1856. Darcy, Henry-Philibert-Gaspard. Recherches expérimentales relatives au mouvement de l'eau dans les tuyaux. Impr. Impériale. Darcy, Henri. Recherches hydrauliques: Recherches expérimentales sur l'écoulement de l'eau dans les canaux découverts. Dunod. Darcy, Henri. Recherches hydrauliques entreprises par M. Henry Darcy continuées par M. Henri Bazin. Paris: Imprimerie impériale. Hydrogeology
Chemical engineering is a branch of engineering that uses principles of chemistry, mathematics and economics to efficiently use, produce and transport chemicals and energy. A chemical engineer designs large-scale processes that convert chemicals, raw materials, living cells and energy into useful forms and products. Chemical engineers are involved in many aspects of plant design and operation, including safety and hazard assessments, process design and analysis, control engineering, chemical reaction engineering, biological engineering, construction specification, operating instructions. Chemical engineering degree is directly linked with all the majors of various engineering disciplines. A 1996 British Journal for the History of Science article cites James F. Donnelly for mentioning an 1839 reference to chemical engineering in relation to the production of sulfuric acid. In the same paper however, George E. Davis, an English consultant, was credited for having coined the term. Davis tried to found a Society of Chemical Engineering, but instead it was named the Society of Chemical Industry, with Davis as its first Secretary.
The History of Science in United States: An Encyclopedia puts the use of the term around 1890. "Chemical engineering", describing the use of mechanical equipment in the chemical industry, became common vocabulary in England after 1850. By 1910, the profession, "chemical engineer," was in common use in Britain and the United States. Chemical engineering emerged upon the development of unit operations, a fundamental concept of the discipline of chemical engineering. Most authors agree that Davis invented the concept of unit operations if not developed it, he gave a series of lectures on unit operations at the Manchester Technical School in 1887, considered to be one of the earliest such about chemical engineering. Three years before Davis' lectures, Henry Edward Armstrong taught a degree course in chemical engineering at the City and Guilds of London Institute. Armstrong's course failed because its graduates were not attractive to employers. Employers of the time would have rather hired mechanical engineers.
Courses in chemical engineering offered by Massachusetts Institute of Technology in the United States, Owens College in Manchester and University College London suffered under similar circumstances. Starting from 1888, Lewis M. Norton taught at MIT the first chemical engineering course in the United States. Norton's course was contemporaneous and similar to Armstrong's course. Both courses, however merged chemistry and engineering subjects along with product design. "Its practitioners had difficulty convincing engineers that they were engineers and chemists that they were not chemists." Unit operations was introduced into the course by William Hultz Walker in 1905. By the early 1920s, unit operations became an important aspect of chemical engineering at MIT and other US universities, as well as at Imperial College London; the American Institute of Chemical Engineers, established in 1908, played a key role in making chemical engineering considered an independent science, unit operations central to chemical engineering.
For instance, it defined chemical engineering to be a "science of itself, the basis of which is... unit operations" in a 1922 report. Meanwhile, promoting chemical engineering as a distinct science in Britain led to the establishment of the Institution of Chemical Engineers in 1922. IChemE helped make unit operations considered essential to the discipline. In 1940s, it became clear that unit operations alone were insufficient in developing chemical reactors. While the predominance of unit operations in chemical engineering courses in Britain and the United States continued until the 1960s, transport phenomena started to experience greater focus. Along with other novel concepts, such as process systems engineering, a "second paradigm" was defined. Transport phenomena gave an analytical approach to chemical engineering while PSE focused on its synthetic elements, such as control system and process design. Developments in chemical engineering before and after World War II were incited by the petrochemical industry, advances in other fields were made as well.
Advancements in biochemical engineering in the 1940s, for example, found application in the pharmaceutical industry, allowed for the mass production of various antibiotics, including penicillin and streptomycin. Meanwhile, progress in polymer science in the 1950s paved way for the "age of plastics". Concerns regarding the safety and environmental impact of large-scale chemical manufacturing facilities were raised during this period. Silent Spring, published in 1962, alerted its readers to the harmful effects of DDT, a potent insecticide; the 1974 Flixborough disaster in the United Kingdom resulted in 28 deaths, as well as damage to a chemical plant and three nearby villages. The 1984 Bhopal disaster in India resulted in 4,000 deaths; these incidents, along with other incidents, affected the reputation of the trade as industrial safety and environmental protection were given more focus. In response, the IChemE required safety to be part of every degree course that it accredited after 1982. By the 1970s, legislation and monitoring agencies were instituted in various countries, such as France and the United States.
Advancements in computer science found applications designing and managing plants, simplifying calculations and drawings that had to be done manually. The c
A petroleum reservoir or oil and gas reservoir is a subsurface pool of hydrocarbons contained in porous or fractured rock formations. Petroleum reservoirs are broadly classified as unconventional reservoirs. In case of conventional reservoirs, the occurring hydrocarbons, such as crude oil or natural gas, are trapped by overlying rock formations with lower permeability. While in unconventional reservoirs the rocks have high porosity and low permeability which keeps the hydrocarbons trapped in place, therefore not requiring a cap rock. Reservoirs are found using hydrocarbon exploration methods. A region with an abundance of oil wells extracting petroleum from below ground; because the oil reservoirs extend over a large area several hundred kilometres across, full exploitation entails multiple wells scattered across the area. In addition, there may be exploratory wells probing the edges, pipelines to transport the oil elsewhere, support facilities; because an oil field may be remote from civilization, establishing a field is an complicated exercise in logistics.
This goes beyond requirements for drilling. For instance, workers require housing to allow them to work onsite for years. In turn and equipment require electricity and water. In cold regions, pipelines may need to be heated. Excess natural gas may be burned off if there is no way to make use of it—which requires a furnace and pipes to carry it from the well to the furnace. Thus, the typical oil field resembles a small, self-contained town in the midst of a landscape dotted with drilling rigs or the pump jacks, which are known as "nodding donkeys" because of their bobbing arm. Several companies, such as Hill International, Esso, Weatherford International, Schlumberger Limited, Baker Hughes and Halliburton, have organizations that specialize in the large-scale construction of the infrastructure and providing specialized services required to operate a field profitably. More than 40,000 oil fields are scattered around the globe, on land and offshore; the largest are the Ghawar Field in Saudi Arabia and the Burgan Field in Kuwait, with more than 60 billion barrels estimated in each.
Most oil fields are much smaller. According to the US Department of Energy, as of 2003 the US alone had over 30,000 oil fields. In the modern age, the location of oil fields with proven oil reserves is a key underlying factor in many geopolitical conflicts; the term "oilfield" is used as a shorthand to refer to the entire petroleum industry. However, it is more accurate to divide the oil industry into three sectors: upstream and downstream. Natural gas originates by the same geological thermal cracking process that converts kerogen to petroleum; as a consequence and natural gas are found together. In common usage, deposits rich in oil are known as oil fields, deposits rich in natural gas are called natural gas fields. In general, organic sediments buried in depths of 1,000 m to 6,000 m generate oil, while sediments buried deeper and at higher temperatures generate natural gas; the deeper the source, the "drier" the gas. Because both oil and natural gas are lighter than water, they tend to rise from their sources until they either seep to the surface or are trapped by a non-permeable stratigraphic trap.
They can be extracted from the trap by drilling. The largest natural gas field is South Pars/Asalouyeh gas field, shared between Iran and Qatar; the second largest natural gas field is the Urengoy gas field, the third largest is the Yamburg gas field, both in Russia. Like oil, natural gas is found underwater in offshore gas fields such as the North Sea, Corrib Gas Field off Ireland, near Sable Island; the technology to extract and transport offshore natural gas is different from land-based fields. It uses a few large offshore drilling rigs, due to the cost and logistical difficulties in working over water. Rising gas prices in the early 21st century encouraged drillers to revisit fields that were not considered economically viable. For example, in 2008 McMoran Exploration passed a drilling depth of over 32,000 feet at the Blackbeard site in the Gulf of Mexico. Exxon Mobil's drill rig there had reached 30,000 feet by 2006 without finding gas, before it abandoned the site. Crude oil is found in all oil reservoirs formed in the Earth's crust from the remains of once-living things.
Evidence indicates that millions of years of heat and pressure changed the remains of microscopic plant and animal into oil and natural gas. Roy Nurmi, an interpretation adviser for Schlumberger oil field services company, described the process as follows: Plankton and algae and the life that's floating in the sea, as it dies, falls to the bottom, these organisms are going to be the source of our oil and gas; when they're buried with the accumulating sediment and reach an adequate temperature, something above 50 to 70 °C they start to cook. This transformation, this change, changes them into the liquid hydrocarbons that move and migrate, will become our oil and gas reservoir. In addition to the aquatic environment, a sea, but might be a river, coral reef or algal mat, the formation of an oil or gas reservoir requires a sedimentary basin that passes through four steps: Deep burial under sand and mud. Pressure cooking. Hydrocarbon migration from the sou
Anisotropy, is the property of being directionally dependent, which implies different properties in different directions, as opposed to isotropy. It can be defined as a difference, when measured along different axes, in a material's physical or mechanical properties An example of anisotropy is light coming through a polarizer. Another is wood, easier to split along its grain than across it. In the field of computer graphics, an anisotropic surface changes in appearance as it rotates about its geometric normal, as is the case with velvet. Anisotropic filtering is a method of enhancing the image quality of textures on surfaces that are far away and steeply angled with respect to the point of view. Older techniques, such as bilinear and trilinear filtering, do not take into account the angle a surface is viewed from, which can result in aliasing or blurring of textures. By reducing detail in one direction more than another, these effects can be reduced. A chemical anisotropic filter, as used to filter particles, is a filter with smaller interstitial spaces in the direction of filtration so that the proximal regions filter out larger particles and distal regions remove smaller particles, resulting in greater flow-through and more efficient filtration.
In NMR spectroscopy, the orientation of nuclei with respect to the applied magnetic field determines their chemical shift. In this context, anisotropic systems refer to the electron distribution of molecules with abnormally high electron density, like the pi system of benzene; this abnormal electron density affects the applied magnetic field and causes the observed chemical shift to change. In fluorescence spectroscopy, the fluorescence anisotropy, calculated from the polarization properties of fluorescence from samples excited with plane-polarized light, is used, e.g. to determine the shape of a macromolecule. Anisotropy measurements reveal the average angular displacement of the fluorophore that occurs between absorption and subsequent emission of a photon. Images of a gravity-bound or man-made environment are anisotropic in the orientation domain, with more image structure located at orientations parallel with or orthogonal to the direction of gravity. Physicists from University of California, Berkeley reported about their detection of the cosine anisotropy in cosmic microwave background radiation in 1977.
Their experiment demonstrated the Doppler shift caused by the movement of the earth with respect to the early Universe matter, the source of the radiation. Cosmic anisotropy has been seen in the alignment of galaxies' rotation axes and polarisation angles of quasars. Physicists use the term anisotropy to describe direction-dependent properties of materials. Magnetic anisotropy, for example, may occur in a plasma, so that its magnetic field is oriented in a preferred direction. Plasmas may show "filamentation", directional. An anisotropic liquid has the fluidity of a normal liquid, but has an average structural order relative to each other along the molecular axis, unlike water or chloroform, which contain no structural ordering of the molecules. Liquid crystals are examples of anisotropic liquids; some materials conduct heat in a way, isotropic, independent of spatial orientation around the heat source. Heat conduction is more anisotropic, which implies that detailed geometric modeling of diverse materials being thermally managed is required.
The materials used to transfer and reject heat from the heat source in electronics are anisotropic. Many crystals are anisotropic to light, exhibit properties such as birefringence. Crystal optics describes light propagation in these media. An "axis of anisotropy" is defined as the axis along; some materials can have multiple such optical axes. Seismic anisotropy is the variation of seismic wavespeed with direction. Seismic anisotropy is an indicator of long range order in a material, where features smaller than the seismic wavelength have a dominant alignment; this alignment leads to a directional variation of elasticity wavespeed. Measuring the effects of anisotropy in seismic data can provide important information about processes and mineralogy in the Earth. Geological formations with distinct layers of sedimentary material can exhibit electrical anisotropy; this property is used in the gas and oil exploration industry to identify hydrocarbon-bearing sands in sequences of sand and shale. Sand-bearing hydrocarbon assets have high resistivity.
Formation evaluation instruments measure this conductivity/resistivity and the results are used to help find oil and gas in wells. The hydraulic conductivity of aquifers is anisotropic for the same reason; when calculating groundwater flow to drains or to wells, the difference between horizontal and vertical permeability must be taken into account, otherwise the results may be subject to error. Most common rock-forming minerals are anisotropic, including feldspar. Anisotropy in minerals is most reliably seen in their optical properties. An example of an isotropic mineral is garnet. Anisotropy is a well-known property in medical ultrasound imaging describing a different resulting echogenicity of soft tissues, such as tendons, wh
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity can be conceptualized as quantifying the frictional force that arises between adjacent layers of fluid that are in relative motion. For instance, when a fluid is forced through a tube, it flows more near the tube's axis than near its walls. In such a case, experiments show; this is because a force is required to overcome the friction between the layers of the fluid which are in relative motion: the strength of this force is proportional to the viscosity. A fluid that has no resistance to shear stress is known as an inviscid fluid. Zero viscosity is observed only at low temperatures in superfluids. Otherwise, the second law of thermodynamics requires all fluids to have positive viscosity. A fluid with a high viscosity, such as pitch, may appear to be a solid; the word "viscosity" is derived from the Latin "viscum", meaning mistletoe and a viscous glue made from mistletoe berries.
In materials science and engineering, one is interested in understanding the forces, or stresses, involved in the deformation of a material. For instance, if the material were a simple spring, the answer would be given by Hooke's law, which says that the force experienced by a spring is proportional to the distance displaced from equilibrium. Stresses which can be attributed to the deformation of a material from some rest state are called elastic stresses. In other materials, stresses are present which can be attributed to the rate of change of the deformation over time; these are called. For instance, in a fluid such as water the stresses which arise from shearing the fluid do not depend on the distance the fluid has been sheared. Viscosity is the material property which relates the viscous stresses in a material to the rate of change of a deformation. Although it applies to general flows, it is easy to visualize and define in a simple shearing flow, such as a planar Couette flow. In the Couette flow, a fluid is trapped between two infinitely large plates, one fixed and one in parallel motion at constant speed u.
If the speed of the top plate is low enough in steady state the fluid particles move parallel to it, their speed varies from 0 at the bottom to u at the top. Each layer of fluid moves faster than the one just below it, friction between them gives rise to a force resisting their relative motion. In particular, the fluid applies on the top plate a force in the direction opposite to its motion, an equal but opposite force on the bottom plate. An external force is therefore required in order to keep the top plate moving at constant speed. In many fluids, the flow velocity is observed to vary linearly from zero at the bottom to u at the top. Moreover, the magnitude F of the force acting on the top plate is found to be proportional to the speed u and the area A of each plate, inversely proportional to their separation y: F = μ A u y; the proportionality factor μ is the viscosity of the fluid, with units of Pa ⋅ s. The ratio u / y is called the rate of shear deformation or shear velocity, is the derivative of the fluid speed in the direction perpendicular to the plates.
If the velocity does not vary linearly with y the appropriate generalization is τ = μ ∂ u ∂ y, where τ = F / A, ∂ u / ∂ y is the local shear velocity. This expression is referred to as Newton's law of viscosity. In shearing flows with planar symmetry, it is what defines μ, it is a special case of the general definition of viscosity, which can be expressed in coordinate-free form. Use of the Greek letter mu for the viscosity is common among mechanical and chemical engineers, as well as physicists. However, the Greek letter eta is used by chemists and the IUPAC; the viscosity μ is sometimes referred to as the shear viscosity. However, at least one author discourages the use of this terminology, noting that μ can appear in nonshearing flows in addition to shearing flows. In general terms, the viscous stresses in a fluid are defined as those resulting from the relative velocity of different fluid particles; as such, the viscous stresses. If the velocity gradients are small to a first approximation the v
Petroleum is a occurring, yellowish-black liquid found in geological formations beneath the Earth's surface. It is refined into various types of fuels. Components of petroleum are separated using a technique called fractional distillation, i.e. separation of a liquid mixture into fractions differing in boiling point by means of distillation using a fractionating column. It consists of occurring hydrocarbons of various molecular weights and may contain miscellaneous organic compounds; the name petroleum covers both occurring unprocessed crude oil and petroleum products that are made up of refined crude oil. A fossil fuel, petroleum is formed when large quantities of dead organisms zooplankton and algae, are buried underneath sedimentary rock and subjected to both intense heat and pressure. Petroleum has been recovered by oil drilling. Drilling is carried out after studies of structural geology, sedimentary basin analysis, reservoir characterisation have been completed, it is refined and separated, most by distillation, into a large number of consumer products, from gasoline and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals.
Petroleum is used in manufacturing a wide variety of materials, it is estimated that the world consumes about 95 million barrels each day. The use of petroleum as fuel is controversial due to its impact on global warming and ocean acidification. Fossil fuels, including petroleum, need to be phased out by the end of 21st century to avoid "severe and irreversable impacts for people and ecosystems", according to the UN's Intergovernmental Panel on Climate Change; the word petroleum comes from Medieval Latin petroleum, which comes from Latin petra', "rock", Latin oleum, "oil". The term was used in the treatise De Natura Fossilium, published in 1546 by the German mineralogist Georg Bauer known as Georgius Agricola. In the 19th century, the term petroleum was used to refer to mineral oils produced by distillation from mined organic solids such as cannel coal, refined oils produced from them. Petroleum, in one form or another, has been used since ancient times, is now important across society, including in economy and technology.
The rise in importance was due to the invention of the internal combustion engine, the rise in commercial aviation, the importance of petroleum to industrial organic chemistry the synthesis of plastics, solvents and pesticides. More than 4000 years ago, according to Herodotus and Diodorus Siculus, asphalt was used in the construction of the walls and towers of Babylon. Great quantities of it were found on the banks of the river Issus, one of the tributaries of the Euphrates. Ancient Persian tablets indicate the medicinal and lighting uses of petroleum in the upper levels of their society; the use of petroleum in ancient China dates back to more than 2000 years ago. In I Ching, one of the earliest Chinese writings cites that oil in its raw state, without refining, was first discovered and used in China in the first century BCE. In addition, the Chinese were the first to use petroleum as fuel as early as the fourth century BCE. By 347 AD, oil was produced from bamboo-drilled wells in China. Crude oil was distilled by Arabic chemists, with clear descriptions given in Arabic handbooks such as those of Muhammad ibn Zakarīya Rāzi.
The streets of Baghdad were paved with tar, derived from petroleum that became accessible from natural fields in the region. In the 9th century, oil fields were exploited in the area around Azerbaijan; these fields were described by the Arab geographer Abu al-Hasan'Alī al-Mas'ūdī in the 10th century, by Marco Polo in the 13th century, who described the output of those wells as hundreds of shiploads. Arab and Persian chemists distilled crude oil in order to produce flammable products for military purposes. Through Islamic Spain, distillation became available in Western Europe by the 12th century, it has been present in Romania since the 13th century, being recorded as păcură. Early British explorers to Myanmar documented a flourishing oil extraction industry based in Yenangyaung that, in 1795, had hundreds of hand-dug wells under production. Pechelbronn is said to be the first European site where petroleum has been used; the still active Erdpechquelle, a spring where petroleum appears mixed with water has been used since 1498, notably for medical purposes.
Oil sands have been mined since the 18th century. In Wietze in lower Saxony, natural asphalt/bitumen has been explored since the 18th century. Both in Pechelbronn as in the coal industry dominated the petroleum technologies. Chemist James Young noticed a natural petroleum seepage in the Riddings colliery at Alfreton, Derbyshire from which he distilled a light thin oil suitable for use as lamp oil, at the same time obtaining a more viscous oil suitable for lubricating machinery. In 1848, Young set up a small business refining the crude oil. Young succeeded, by distilling cannel coal at a low heat, in creating a fluid resembling petroleum, which when treated in the same way as the seep oil gave similar products. Young found that by sl