The Joule expansion, in which a volume Vi = V0 is expanded to a volume Vf = 2V0 in a thermally isolated chamber.A free expansion of a gas can be achieved by moving the piston out faster than the fastest molecules in the gas.This free expansion is irreversible but can be quasi-static for each chamber: quasi-equilibrium is retained for each part but not for the whole system
The Joule expansion (a subset of free expansion) is an irreversible process in thermodynamics in which a volume of gas is kept in one side of a thermally isolated container (via a small partition), with the other side of the container being evacuated. The partition between the two parts of the container is then opened, and the gas fills the whole container.
The Joule expansion, treated as a thought experiment involving ideal gases, is a useful exercise in classical thermodynamics. It provides a convenient example for calculating changes in thermodynamic quantities, including the resulting increase in entropy of the universe (entropy production) that results from this inherently irreversible process. An actual Joule expansion experiment necessarily involves real gases; the temperature change in such a process provides a measure of intermolecular forces.
This type of expansion is named after James Prescott Joule who used this expansion, in 1845, in his study for the mechanical equivalent of heat, but this expansion was known long before Joule e.g. by John Leslie, in the beginning of the 19th century, and studied by Joseph-Louis Gay-Lussac in 1807 with similar results as obtained by Joule.[1][2]
The Joule expansion should not be confused with the Joule–Thomson expansion or throttling process which refers to the steady flow of a gas from a region of higher pressure to one of lower pressure via a valve or porous plug.
^D.S.L. Cardwell, From Watt to Clausius, Heinemann, London (1957)
^M.J. Klein, Principles of the theory of heat, D. Reidel Pub.Cy., Dordrecht (1986)
The Jouleexpansion (a subset of free expansion) is an irreversible process in thermodynamics in which a volume of gas is kept in one side of a thermally...
field. The Joule effect (during Jouleexpansion), the temperature change of a gas (usually cooling) when it is allowed to expand freely. The Joule–Thomson...
In microscopy, scanning jouleexpansion microscopy (SJEM) is a form of scanning probe microscopy heavily based on atomic force microscopy (AFM) that maps...
the universe is equal to ΔS for the system. Joule–Thomson effect Jouleexpansion (also called free expansion) Adiabatic process Cyclic process Isobaric...
Joule FRS FRSE (/dʒuːl/; 24 December 1818 – 11 October 1889) was an English physicist, mathematician and brewer, born in Salford, Lancashire. Joule studied...
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flow through a flow resistance such as in the Jouleexpansion or the Joule–Thomson effect heat transfer Joule heating friction between solid surfaces fluid...
a process is reversible if there is no dissipation. For example, Jouleexpansion is irreversible because initially the system is not uniform. Initially...
Thermal expansion is the tendency of matter to change its shape, area, volume, and density in response to a change in temperature, usually not including...
output Expansion joint, an assembly that absorbs heat-induced expansion and contraction of construction materials Joule–Thomson effect or Joule–Thomson...
the development of expansion microscopy, scientists have begun to create subsets of the technique, including scanning Jouleexpansion microscopy, or SJEM...
refinement of the famous Maxwell's demon scenario (and a reversal of the Jouleexpansion thought experiment). Consider Maxwell's set-up, but with only a single...
the Meyer expansion valve, the invention of Jean-Jacques Meyer A valve used to expand a gas, for thermodynamic cooling purposes in either: Joule-Thomson...
capacity is joule per kelvin per kilogram, J⋅kg−1⋅K−1. For example, the heat required to raise the temperature of 1 kg of water by 1 K is 4184 joules, so the...
for thermodynamics since its early days. It was important in the work of Joule because it provided a way of nearly directly relating quantities of heat...
divided by the mass, giving the terms units of joules/kg (specific energy), meters3/kg (specific volume), or joules/(kelvin·kg) (specific entropy, heat capacity)...
specialized types of probes (see scanning thermal microscopy, scanning jouleexpansion microscopy, photothermal microspectroscopy, etc.). The AFM can be operated...
is much lower than 200 bar. A more detailed description of Joule-Thomson coolers and Joule-Thomson refrigerators can be found in. Cryocoolers are a key...
of enthalpy is the so-called throttling process, also known as Joule–Thomson expansion. It concerns a steady adiabatic flow of a fluid through a flow...
terms of energy by setting the Boltzmann constant to exactly 1.380649×10−23 joules per kelvin; every 1 K change of thermodynamic temperature corresponds to...
bearings. Air separation Dry gas seal Flash evaporation Gas compressor Joule-Thomson effect Liquefaction of gases Rankine cycle Steam turbine Vapor-compression...
measurement for heat, as a form of energy, is the joule (J). As a form of energy, heat has the unit joule (J) in the International System of Units (SI)....
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