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Crocco's Theorem
Crocco's theorem is an aerodynamic theorem relating the flow velocity, vorticity, and stagnation pressure (or entropy) of a potential flow. Crocco's theorem gives the relation between the thermodynamics and fluid kinematics. The theorem was first enunciated by Alexander Friedmann for the particular case of a perfect gas and published in 1922: :\frac=T \nabla\,s-\nabla \,h However, usually this theorem is connected with the name of Italian scientist Luigi Crocco,Crocco LEine neue Stromfunktion für die Erforschung der Bewegung der Gase mit Rotation ZAMM, Vol. 17, Issue 1, pp. 1–7, 1937. DOI: 10.1002/zamm.19370170103. Crocco writes the theorem in the form \scriptstyle\mathrm\,\mathbf u\times\mathbf u=T\mathrm\,S for perfect gas (the last formula on page 2). a son of Gaetano Crocco Gaetano Arturo Crocco (26 October 1877 – 19 January 1968) was an Italian scientist and aeronautics pioneer, the founder of the Italian Rocket Society, and went on to become Italy's leading ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerodynamic
Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), 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. 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 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikolai Kochin
Nikolai Yevgrafovich Kochin (russian: Николай Евграфович Кочин; 19 May 1901, St Petersburg – 31 December 1944, Moscow) was a Russian and Soviet mathematician specialising in applied mathematics, and especially fluid and gas mechanics. Biography Kochin graduated from Petrograd University in 1923. He taught mathematics and mechanics at Leningrad State University from 1924 to 1934. In 1925 Kochin married Pelageya Polubarinova. They had two daughters. In 1928 Kochin spent a semester in Göttingen, where he helped Gamow to solve the alpha decay problem through quantum tunneling. Colorado, April 25, 1968 Kochin moved to |
Body Force
In physics, a body force is a force that acts throughout the volume of a body. Springer site - Book 'Solid mechanics'preview paragraph 'Body forces'./ref> Forces due to gravity, electric fields and magnetic fields are examples of body forces. Body forces contrast with contact forces or surface forces which are exerted to the surface of an object. Normal forces and shear forces between objects are surface forces as they are exerted to the surface of an object. All cohesive surface attraction and contact forces between objects are also considered as surface forces. Fictitious forces such as the centrifugal force, Euler force, and the Coriolis effect are other examples of body forces. Definition Qualitative A body force is simply a type of force, and so it has the same dimensions as force, L] sup>−2. However, it is often convenient to talk about a body force in terms of either the force per unit volume or the force per unit mass. If the force per unit volume is of int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enthalpy
Enthalpy , a property of a thermodynamic system, is the sum of the system's internal energy and the product of its pressure and volume. It is a state function used in many measurements in chemical, biological, and physical systems at a constant pressure, which is conveniently provided by the large ambient atmosphere. The pressure–volume term expresses the work required to establish the system's physical dimensions, i.e. to make room for it by displacing its surroundings. The pressure-volume term is very small for solids and liquids at common conditions, and fairly small for gases. Therefore, enthalpy is a stand-in for energy in chemical systems; bond, lattice, solvation and other "energies" in chemistry are actually enthalpy differences. As a state function, enthalpy depends only on the final configuration of internal energy, pressure, and volume, not on the path taken to achieve it. In the International System of Units (SI), the unit of measurement for enthalpy is the j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperature
Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have relied on various reference points and thermometric substances for definition. The most common scales are the Celsius scale with the unit symbol °C (formerly called ''centigrade''), the Fahrenheit scale (°F), and the Kelvin scale (K), the latter being used predominantly for scientific purposes. The kelvin is one of the seven base units in the International System of Units (SI). Absolute zero, i.e., zero kelvin or −273.15 °C, is the lowest point in the thermodynamic temperature scale. Experimentally, it can be approached very closely but not actually reached, as recognized in the third law of thermodynamics. It would be impossible to extract energy as heat from a body at that temperature. Temperature is important in all fields of na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaetano Crocco
Gaetano Arturo Crocco (26 October 1877 – 19 January 1968) was an Italian scientist and aeronautics pioneer, the founder of the Italian Rocket Society, and went on to become Italy's leading space scientist. He was born in Naples. In 1927, Crocco begun working with solid-propellant rockets and, in 1929, designed and built the first liquid rocket propellants, liquid-propellant rocket motors in Italy. He began work with monopropellants (fuel and oxidizer combined in one chemical liquid) in 1932, making him one of the first researchers in this field. As head of the School of Aeronautics of the University of Rome La Sapienza, University of Rome, he performed research on flight mechanics, structural design, and high-altitude flight in addition to his work in rocket propulsion. Because of his early efforts in aeronautics, Italian satellites were launched starting in the 1960s. The San Marco programme was a cooperative effort of NASA and the Italian Space Commission, with NASA providi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Applied Mathematics And Mechanics
The ''Journal of Applied Mathematics and Mechanics'', also known as ''Zeitschrift für Angewandte Mathematik und Mechanik'' or ''ZAMM'' is a monthly peer-reviewed scientific journal dedicated to applied mathematics. It is published by Wiley-VCH on behalf of the Gesellschaft für Angewandte Mathematik und Mechanik. The editor-in-chief is Holm Altenbach (Otto von Guericke University Magdeburg). According to the ''Journal Citation Reports'', the journal has a 2021 impact factor of 1.759. Publication history The journal's first issue appeared in 1921, published by the Verein Deutscher Ingenieure and edited by Richard von Mises. in the |
Luigi Crocco
is a fictional character featured in video games and related media released by Nintendo. Created by Japanese video game designer Shigeru Miyamoto, Luigi is portrayed as the younger fraternal twin brother and sidekick of Mario, Nintendo's mascot. Luigi appears in many games throughout the ''Mario'' franchise, oftentimes accompanying his brother. Luigi first appeared in the 1983 Game & Watch game '' Mario Bros.'', where he is the character controlled by the second player. He would retain this role in many future games, including '' Mario Bros.'', '' Super Mario Bros.'', ''Super Mario Bros. 3'', '' Super Mario World'', among other titles. He was first available as a primary character in ''Super Mario Bros. 2''. In more recent appearances, Luigi's role became increasingly restricted to spinoffs, such as the '' Mario Party'' and ''Mario Kart'' series; however, he has been featured in a starring role in '' Luigi's Hammer Toss'', ''Mario is Missing'', ''Luigi's Mansion'', '' Luig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saint Petersburg
Saint Petersburg ( rus, links=no, Санкт-Петербург, a=Ru-Sankt Peterburg Leningrad Petrograd Piter.ogg, r=Sankt-Peterburg, p=ˈsankt pʲɪtʲɪrˈburk), formerly known as Petrograd (1914–1924) and later Leningrad (1924–1991), is the List of cities and towns in Russia by population, second-largest city in Russia. It is situated on the Neva River, at the head of the Gulf of Finland on the Baltic Sea, with a population of roughly 5.4 million residents. Saint Petersburg is the List of European cities by population within city limits, fourth-most populous city in Europe after Istanbul, Moscow and London, the List of cities and towns around the Baltic Sea, most populous city on the Baltic Sea, and the world's List of northernmost items#Cities and settlements, northernmost city of more than 1 million residents. As Russia's Imperial capital, and a Ports of the Baltic Sea, historically strategic port, it is governed as a Federal cities of Russia, federal city. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flow Velocity
In continuum mechanics the flow velocity in fluid dynamics, also macroscopic velocity in statistical mechanics, or drift velocity in electromagnetism, is a vector field used to mathematically describe the motion of a continuum. The length of the flow velocity vector is the flow speed and is a scalar. It is also called velocity field; when evaluated along a line, it is called a velocity profile (as in, e.g., law of the wall). Definition The flow velocity ''u'' of a fluid is a vector field : \mathbf=\mathbf(\mathbf,t), which gives the velocity of an '' element of fluid'' at a position \mathbf\, and time t.\, The flow speed ''q'' is the length of the flow velocity vector :q = \, \mathbf \, and is a scalar field. Uses The flow velocity of a fluid effectively describes everything about the motion of a fluid. Many physical properties of a fluid can be expressed mathematically in terms of the flow velocity. Some common examples follow: Steady flow The flow of a fluid i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfect Gas
In physics and engineering, a perfect gas is a theoretical gas model that differs from real gases in specific ways that makes certain calculations easier to handle. In all perfect gas models, intermolecular forces are neglected. This means that one can neglect many complications that may arise from the Van der Waals forces. All perfect gas models are ideal gas models in the sense that they all follow the ideal gas equation of state. However, the idea of a perfect gas model is often invoked as a combination of the ideal gas equation of state with specific additional assumptions regarding the variation (or nonvariation) of the heat capacity with temperature. Perfect gas nomenclature The terms ''perfect gas'' and ''ideal gas'' are sometimes used interchangeably, depending on the particular field of physics and engineering. Sometimes, other distinctions are made, such as between ''thermally perfect gas'' and ''calorically perfect gas'', or between imperfect, semi-perfect, and perfect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Friedmann
Alexander Alexandrovich Friedmann (also spelled Friedman or Fridman ; russian: Алекса́ндр Алекса́ндрович Фри́дман) (June 16 .S. 4 1888 – September 16, 1925) was a Russian and Soviet physicist and mathematician. He is best known for his pioneering theory that the universe was expanding, governed by a set of equations he developed now known as the Friedmann equations. Early life Alexander Friedmann was born to the composer and ballet dancer Alexander Friedmann (who was a son of a baptized Jewish cantonist) and the pianist Ludmila Ignatievna Voyachek (who was a daughter of the Czech composer Hynek Vojáček). Friedmann was baptized into the Russian Orthodox Church as an infant, and lived much of his life in Saint Petersburg. Friedmann obtained his degree from St. Petersburg State University in 1910, and became a lecturer at Saint Petersburg Mining Institute. From his school days, Friedmann found a lifelong companion in Jacob Tamarkin, who w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
