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Z-pinch
In fusion power research, the Z-pinch (zeta pinch) is a type of plasma confinement system that uses an electric current in the plasma to generate a magnetic field that compresses it (see pinch). These systems were originally referred to simply as pinch or Bennett pinch (after Willard Harrison Bennett), but the introduction of the θ-pinch (theta pinch) concept led to the need for clearer, more precise terminology. The name refers to the direction of the current in the devices, the Z-axis on a normal three-dimensional graph. Any machine that causes a pinch effect due to current running in that direction is correctly referred to as a Z-pinch system, and this encompasses a wide variety of devices used for an equally wide variety of purposes. Early uses focused on fusion research in donut-shaped tubes with the Z-axis running down the inside the tube, while modern devices are generally cylindrical and used to generate high-intensity x-ray sources for the study of nuclear weapons an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinch (plasma Physics)
A pinch (or: Bennett pinch (after Willard Harrison Bennett), electromagnetic pinch, magnetic pinch, pinch effect, or plasma pinch.) is the compression of an electrically conducting filament by magnetic forces, or a device that does such. The conductor is usually a plasma, but could also be a solid or liquid metal. Pinches were the first type of device used for experiments in controlled nuclear fusion power. Pinches occur naturally in electrical discharges such as lightning bolts, planetary auroras, current sheets, and solar flares. Basic mechanism Types Pinches exist in nature and in laboratories. Pinches differ in their geometry and operating forces. These include: * ''Uncontrolled'' – Any time an electric current moves in large amounts (e.g., lightning, arcs, sparks, discharges) a magnetic force can pull together plasma. This can be insufficient for fusion. * '' Sheet pinch'' – An astrophysical effect, this arises from vast sheets of charged particles. * ''Z-pinch'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z-pinch H-gamma
In fusion power research, the Z-pinch (zeta pinch) is a type of plasma confinement system that uses an electric current in the plasma to generate a magnetic field that compresses it (see pinch). These systems were originally referred to simply as pinch or Bennett pinch (after Willard Harrison Bennett), but the introduction of the θ-pinch (theta pinch) concept led to the need for clearer, more precise terminology. The name refers to the direction of the current in the devices, the Z-axis on a normal three-dimensional graph. Any machine that causes a pinch effect due to current running in that direction is correctly referred to as a Z-pinch system, and this encompasses a wide variety of devices used for an equally wide variety of purposes. Early uses focused on fusion research in donut-shaped tubes with the Z-axis running down the inside the tube, while modern devices are generally cylindrical and used to generate high-intensity x-ray sources for the study of nuclear weapons an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perhapsatron
The Perhapsatron was an early fusion power device based on the pinch concept in the 1950s. Conceived by James (Jim) Tuck while working at Los Alamos National Laboratory (LANL), he whimsically named the device on the chance that it might be able to create fusion reactions. The first example was built in the winter of 1952/53, and it quickly demonstrated a series of instabilities in the plasma that plagued the pinch concept. A series of modifications followed which attempted to correct these problems, leading to the ultimate "S-4" model. None of these proved fruitful. History Early fusion efforts Scientists at Los Alamos National Laboratory had a long history of studying nuclear fusion, and by 1946 they had calculated that a steady-state plasma would have to be heated to 100 million degrees Celsius (180 million degrees Fahrenheit) to "ignite" and release net energy. This was of vital interest in the nuclear bomb establishment, where the use of a small atomic bomb "trigger" was us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sceptre (fusion Reactor)
Sceptre was an early fusion power device based on the Z-pinch concept of plasma confinement, built in the UK starting in 1957. They were the ultimate versions of a series of devices tracing their history to the original pinch machines, built at Imperial College London by Cousins and Ware in 1947. When the UK's fusion work was classified in 1950, Ware's team was moved to the Associated Electrical Industries (AEI) labs at Aldermaston. The team worked on the problems associated with using metal tubes with high voltages, in support of the efforts at Harwell. When Harwell's ZETA machine apparently produced fusion, AEI quickly built a smaller machine, Sceptre, to test their results. Sceptre also produced neutrons, apparently confirming the ZETA experiment. It was later found that the neutrons were spurious, and UK work on Z-pinch ended in the early 1960s. History Background Fusion research in the UK started on a shoestring budget at Imperial College in 1946. When George Paget Thomso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusion Power
Fusion power is a proposed form of power generation that would generate electricity by using heat from nuclear fusion, nuclear fusion reactions. In a fusion process, two lighter atomic nucleus, atomic nuclei combine to form a heavier nucleus, while releasing energy. Devices designed to harness this energy are known as fusion reactors. Research into fusion reactors began in the 1940s, but as of 2022, only one design, an Inertial confinement fusion, inertial confinement laser-driven fusion machine at the US National Ignition Facility, has conclusively produced a positive fusion energy gain factor, i.e. more power output than input. Fusion processes require fuel and a confined environment with sufficient temperature, pressure, and confinement time to create a plasma (physics), plasma in which fusion can occur. The combination of these figures that results in a power-producing system is known as the Lawson criterion. In stars, the most common fuel is hydrogen, and gravity provides ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ZETA (fusion Reactor)
ZETA, short for Zero Energy Thermonuclear Assembly, was a major experiment in the early history of fusion power research. Based on the Z-pinch, pinch Plasma (physics), plasma confinement technique, and built at the Atomic Energy Research Establishment in the United Kingdom, ZETA was larger and more powerful than any fusion machine in the world at that time. Its goal was to produce large numbers of fusion reactions, although it was not large enough to produce net energy. ZETA went into operation in August 1957 and by the end of the month it was giving off bursts of about a million neutrons per pulse. Measurements suggested the fuel was reaching between 1 and 5 million kelvins, a temperature that would produce nuclear fusion reactions, explaining the quantities of neutrons being seen. Early results were leaked to the press in September 1957, and the following January an extensive review was released. Front-page articles in newspapers around the world announced it as a breakthro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kink Instability
A kink instability (also kink oscillation or kink mode), is a current-driven plasma instability characterized by transverse displacements of a plasma column's cross-section from its center of mass without any change in the characteristics of the plasma. It typically develops in a thin plasma column carrying a strong axial current which exceeds the Kruskal–Shafranov limit and is sometimes known as the Kruskal–Shafranov (kink) instability. The kink instability was first widely explored in fusion power machines with Z-pinch configurations in the 1950s. It is one of the common magnetohydrodynamic instability modes which can develop in a pinch plasma and is sometimes referred to as the m=1 mode. (The other is the m=0 mode known as the sausage instability.) If a "kink" begins to develop in a column the magnetic force In physics (specifically in electromagnetism) the Lorentz force (or electromagnetic force) is the combination of electric and magnetic force on a point charge due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable metallic form ( native metals). This led to very early human use in several regions, from circa 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, circa 5000 BC; the first metal to be cast into a shape in a mold, c. 4000 BC; and the first metal to be purposely alloyed with another metal, tin, to create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tokamak
A tokamak (; russian: токамáк; otk, 𐱃𐰸𐰢𐰴, Toḳamaḳ) is a device which uses a powerful magnetic field to confine plasma in the shape of a torus. The tokamak is one of several types of magnetic confinement devices being developed to produce controlled thermonuclear fusion power. , it was the leading candidate for a practical fusion reactor. Tokamaks were initially conceptualized in the 1950s by Soviet physicists Igor Tamm and Andrei Sakharov, inspired by a letter by Oleg Lavrentiev. The first working tokamak was attributed to the work of Natan Yavlinsky on the T-1 in 1958. It had been demonstrated that a stable plasma equilibrium requires magnetic field lines that wind around the torus in a helix. Devices like the z-pinch and stellarator had attempted this, but demonstrated serious instabilities. It was the development of the concept now known as the safety factor (labelled ''q'' in mathematical notation) that guided tokamak development; by arranging the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust
Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that system. The force applied on a surface in a direction perpendicular or normal to the surface is also called thrust. Force, and thus thrust, is measured using the International System of Units (SI) in newtons (symbol: N), and represents the amount needed to accelerate 1 kilogram of mass at the rate of 1 meter per second per second. In mechanical engineering, force orthogonal to the main load (such as in parallel helical gears) is referred to as static thrust. Examples A fixed-wing aircraft propulsion system generates forward thrust when air is pushed in the direction opposite to flight. This can be done by different means such as the spinning blades of a propeller, the propelling jet of a jet engine, or by ejecting hot gases from a rocket ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Impulse
Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse is exactly proportional to the effective exhaust gas velocity. A propulsion system with a higher specific impulse uses the mass of the propellant more efficiently. In the case of a rocket, this means less propellant needed for a given delta-v, so that the vehicle attached to the engine can more efficiently gain altitude and velocity. In an atmospheric context, specific impulse can include the contribution to impulse provided by the mass of external air that is accelerated by the engine in some way, such as by an internal turbofan or heating by fuel combustion participation then thrust expansion or by external propeller. Jet engines breathe external air for both combustion and by-pass, and therefore have a much higher specific impulse than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
