|
Heat Transfer Enhancement
Heat transfer enhancement is the process of increasing the effectiveness of Heat exchanger, heat exchangers. This can be achieved when the heat transfer power of a given device is increased or when the pressure losses generated by the device are reduced. A variety of techniques can be applied to this effect, including generating strong Secondary flow, secondary flows or increasing boundary layer turbulence. Principle During the earliest attempts to enhance heat transfer, plain (or smooth) surfaces were used. This surface requires a special surface geometry able to provide higher values per unit surface area in comparison with a plain surface. The ratio of of an enhanced heat transfer surface to the plain surface is called Enhancement Ratio " E_h ". Thus, E_h= The heat transfer rate for a two-fluid counterflow heat exchanger is given by In order to better illustrate the benefits of enhancement, the total length 'L' of the tube is multiplied and divided in the eq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Exchanger
A heat exchanger is a system used to transfer heat between a source and a working fluid. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants, Petrochemical, petrochemical plants, Oil refinery, petroleum refineries, natural-gas processing, and sewage treatment. The classic example of a heat exchanger is found in an internal combustion engine in which a circulating fluid known as engine coolant flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air. Another example is the heat sink, which is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant. Flow arrangement There are three primary classifications of heat exchangers accord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Transfer
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, Convection (heat transfer), thermal convection, thermal radiation, and transfer of energy by phase changes. Engineers also consider the transfer of mass of differing chemical species (mass transfer in the form of advection), either cold or hot, to achieve heat transfer. While these mechanisms have distinct characteristics, they often occur simultaneously in the same system. Heat conduction, also called diffusion, is the direct microscopic exchanges of kinetic energy of particles (such as molecules) or quasiparticles (such as lattice waves) through the boundary between two systems. When an object is at a different temperature from another body or its surroundings, heat flows so that the body and the surroundings reach the same temperature, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Flow
In fluid dynamics, flow can be decomposed into primary flow plus secondary flow, a relatively weaker flow pattern superimposed on the stronger primary flow pattern. The primary flow is often chosen to be an exact solution to simplified or approximated governing equations, such as potential flow around a wing or geostrophic current or wind on the rotating Earth. In that case, the secondary flow usefully spotlights the effects of complicated real-world terms neglected in those approximated equations. For instance, the consequences of viscosity are spotlighted by secondary flow in the viscous boundary layer, resolving the tea leaf paradox. As another example, if the primary flow is taken to be a balanced flow approximation with net force equated to zero, then the secondary circulation helps spotlight acceleration due to the mild imbalance of forces. A smallness assumption about secondary flow also facilitates linearization. In engineering, secondary flow also identifies an additi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boundary Layer
In physics and fluid mechanics, a boundary layer is the thin layer of fluid in the immediate vicinity of a Boundary (thermodynamic), bounding surface formed by the fluid flowing along the surface. The fluid's interaction with the wall induces a No-slip condition, no-slip boundary condition (zero velocity at the wall). The flow velocity then monotonically increases above the surface until it returns to the bulk flow velocity. The thin layer consisting of fluid whose velocity has not yet returned to the bulk flow velocity is called the velocity boundary layer. The air next to a human is heated, resulting in gravity-induced convective airflow, which results in both a velocity and thermal boundary layer. A breeze disrupts the boundary layer, and hair and clothing protect it, making the human feel cooler or warmer. On an aircraft wing, the velocity boundary layer is the part of the flow close to the wing, where viscosity, viscous forces distort the surrounding non-viscous flow. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two Fluid Counter-flow
2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and the only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many cultures. Mathematics The number 2 is the second natural number after 1. Each natural number, including 2, is constructed by succession, that is, by adding 1 to the previous natural number. 2 is the smallest and the only even prime number, and the first Ramanujan prime. It is also the first superior highly composite number, and the first colossally abundant number. An integer is determined to be even if it is divisible by two. When written in base 10, all multiples of 2 will end in 0, 2, 4, 6, or 8; more generally, in any even base, even numbers will end with an even digit. A digon is a polygon with two sides (or edges) and two vertices. Two distinct points in a plane are always sufficient to define a unique line in a nontr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Transfer Coefficient
In thermodynamics, the heat transfer coefficient or film coefficient, or film effectiveness, is the Proportional (mathematics), proportionality constant between the heat flux and the thermodynamic driving force for the Heat transfer, flow of heat (i.e., the Temperature gradient, temperature difference, ). It is used to calculate heat transfer between components of a system; such as by convection between a fluid and a solid. The heat transfer coefficient has SI units in Watt, watts per square meter per kelvin (W/(m2K)). The overall heat transfer rate for combined modes is usually expressed in terms of an overall Thermal conduction, conductance or heat transfer coefficient, . Upon reaching a steady state of flow, the heat transfer rate is: :\dot=hA(T_2-T_1) where (in SI units): : \dot: Heat transfer rate (W) : h: Heat transfer coefficient (W/m2K) : A: surface area where the heat transfer takes place (m2) : T_2: temperature of the surrounding fluid (K) : T_1: temperature of the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Resistance
In heat transfer, thermal engineering, and thermodynamics, thermal conductance and thermal resistance are fundamental concepts that describe the ability of materials or systems to conduct heat and the opposition they offer to the heat current. The ability to manipulate these properties allows engineers to control temperature gradient, prevent thermal shock, and maximize the efficiency of thermal systems. Furthermore, these principles find applications in a multitude of fields, including materials science, mechanical engineering, electronics, and energy management. Knowledge of these principles is crucial in various scientific, engineering, and everyday applications, from designing efficient temperature control, thermal insulation, and thermal management in industrial processes to optimizing the performance of electronic devices. Thermal conductance (''G'') measures the ability of a material or system to conduct heat. It provides insights into the ease with which heat can pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coil Spring Wire Insert
Coil or COIL may refer to: Geometry * Helix, a space curve that winds around a line * Spiral, a curve that winds around a central point Science and technology * Coil (chemistry), a tube used to cool and condense steam from a distillation * Coil spring, used to store energy, absorb shock, or maintain a force between two surfaces * Inductor or coil, a passive two-terminal electrical component * Electromagnetic coil, formed when a conductor is wound around a core or form to create an inductor or electromagnet ** Induction coil, a type of electrical transformer used to produce high-voltage pulses from a low-voltage direct current supply *** Ignition coil, used in internal combustion engines to create a pulse of high voltage for a spark plug * Intrauterine device or coil, a contraceptive device * Chemical oxygen iodine laser, a near–infrared chemical laser * Coil, a binary digit or bit in some communication protocols such as Modbus * COIL, the gene that encodes the protein coilin * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Twisted Tape Tube Insert
Twisted may refer to: Film and television * ''Twisted'' (1986 film), a horror film by Adam Holender starring Christian Slater * ''Twisted'' (1996 film), a modern retelling of ''Oliver Twist'' * ''Twisted'', a 2011 Singapore Chinese film directed by Chai Yee Wei * ''Twisted'' (2004 film), a thriller starring Ashley Judd and Andy Garcia * ''Twisted'' (TV series), 2013 * "Twisted" (''Star Trek: Voyager''), a television episode Software and games * '' Twisted: The Game Show'', a 1994 3DO game * Twisted (software), an event-driven networking framework * '' WarioWare: Twisted!'', a 2004 game for the Game Boy Advance Books * ''Twisted'' (short story collection), a short story collection by crime writer Jeffery Deaver ** '' More Twisted'', a second short story collection by Deaver * Twisted (Anderson novel), a novel by Laurie Halse Anderson * ''Twisted'', a ''Pretty Little Liars'' novel by Sara Shepard Brands * Creme Egg Twisted, a chocolate bar Music * Twisted (musical)">''T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longitudinal Fins
Longitudinal is a geometric term of location which may refer to: * Longitude ** Line of longitude, also called a meridian * Longitudinal engine, an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle, front to back * Longitudinal mode, a particular standing wave pattern of a resonant cavity formed by waves confined in the cavity * Longitudinal redundancy check, in telecommunication, a form of redundancy check that is applied independently to each of a parallel group of bit streams. * Longitudinal study, a research study that involves repeated observations of the same items over long periods of time — often many decades * Longitudinal voltage, in telecommunication, a voltage induced or appearing along the length of a transmission medium * Longitudinal wave, a wave with oscillations or vibrations along or parallel to their direction of travel * Longitudinal/longitudinally are also anatomical terms of location. See also * Latitudinal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helical Ribs
Helical may refer to: * Helix, the mathematical concept for the shape * Helical engine, a proposed spacecraft propulsion drive * Helical spring, a coilspring * Helical plc, a British property company, once a maker of steel bar stock * Helicoil A threaded insert, also known as a threaded bushing, is a fastener element that is inserted into an object to add a threaded hole. They may be used to repair a stripped threaded hole, provide a durable threaded hole in a soft material, place a t ..., a mechanical thread repairing insert * H-el-ical//, stage name for Hikaru, Japanese singer {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convection
Convection is single or Multiphase flow, multiphase fluid flow that occurs Spontaneous process, spontaneously through the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be assumed. Convection may also take place in soft solids or mixtures where particles can flow. Convective flow may be Transient state, transient (such as when a Multiphasic liquid, multiphase mixture of oil and water separates) or steady state (see convection cell). The convection may be due to Gravity, gravitational, Electromagnetism, electromagnetic or Fictitious force, fictitious body forces. Convection (heat transfer), Heat transfer by natural convection plays a role in the structure of Earth's atmosphere, its oceans, and its Earth's mantle, mantle. Discrete convective cells in the atmosphere can be identified by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
