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I recently have discovered that the thermodynamics term "adiabatic" seem to be used slightly differently in Britain than it is in North America.
What does "adiabatic" mean in Britain?
What does "adiabatic" mean in Britain?
D H said:But then he writes about adiabatic surfaces where those in the US would use the word isentropic instead. It appears that a few other UK sites also use adiabatic where we would use isentropic.
IIRC, the adiabatic lapse rate is defined as ##(\partial T/\partial z)_Q##, in other words, change in temperature with elevation given no heat transfer. (Compare the environmental lapse rate, ##dT/dz## in the "real" atmosphere.)CAF123 said:There is a quantity of interest in oceanography called, confusingly, the adiabatic lapse rate defined as ##(\partial T/\partial P)_S## even though the thermodynamic derivative is isentropic or at constant entropy. Ofcourse, the latter term is more appropriate.
CAF123 said:I was not aware of any differences in the term. In the context of thermodynamics, an adiabatic process is one in which there is no heat transfer over the system/surroundings boundary. The Oxford dictionary has a similar definition, see http://www.oxforddictionaries.com/definition/english/adiabatic .
Where did you hear about a difference?
CAF123 said:From the first book: 'We define a change to be adiabatic if it is both adiathermal and reversible
The expansion is clearly adiathermal, since the symmetry means that there can be no net heat flow through any surface. If the expansion is also reversible, then we can go one step further, because entropy change is defined in terms of the heat that flows during a reversible change. If no heat flows during a reversible change, then entropy must be conserved, and the expansion will be adiabatic.
peteratcam said:A process is called adiathermal if there is no heat flux from the surroundings during it. A process is called adiabatic if it is both adiathermal and also \Delta S = 0.
That seems to be the same John Peacock who is a professor of cosmology at the university I attend. I guess one needs to specify how they are defining their terms. For example, with that reference of the adiabatic lapse rate, a piece of follow-up text was explaining that an adiabatic process is not necessarily isentropic. So clearly here they were meaning 'adiabatic' here to mean 'adiathermal' in the terms used in those books.George Jones said:In his book "Cosmological Physics", John Peacock writes (Peacock's bold)
The term "adiabatic" in Britain refers to a process in which there is no exchange of heat with the surroundings. It is commonly used in meteorology and thermodynamics to describe changes in temperature without the influence of external heat or energy.
In Britain, adiabatic processes play a crucial role in shaping weather patterns and overall climate. For example, the adiabatic cooling of air as it rises and expands can lead to the formation of clouds and precipitation, while adiabatic warming can result in dry and sunny conditions.
Some common examples of adiabatic processes in nature include the formation of thunderstorms, wind patterns, and the Earth's atmospheric circulation. Additionally, the adiabatic cooling of air in higher altitudes is responsible for the formation of snow and glaciers in mountainous regions.
While adiabatic processes involve no heat exchange, isothermal processes maintain a constant temperature through heat exchange with the surroundings. In other words, adiabatic processes are thermally isolated, while isothermal processes are not.
Understanding adiabatic processes is essential for predicting and mitigating weather patterns and climate change in Britain. It also has practical applications in industries such as meteorology, energy production, and air conditioning, where the manipulation of temperature is crucial.