Adiabatic Process Thermodynamics

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Adiabatic Process Thermodynamic

An adiabatic process is one in which there is no heat transfer into or out of the system. The system can beconsidered to be perfectly insulated.

A key concept in thermodynamics , the adiabatic process provides a rigorous conceptual basis for the theory used to expound the first law of thermodynamics .

For some practical and theoretical purposes, some chemical and physical processes occur so rapidly that they can be conveniently described as an "adiabatic approximation", meaning that there is hardly time for transfer of energy as heat. Such processes are often followed or preceded by processes that are not adiabatic.

The adiabatic flame temperature is an idealization that provides a convenient approximation. It is the temperature that would be achieved by a flame in the absence of heat loss to the surroundings.


A process that does not involve the transfer of heat into or out of a system Q = 0, is called an adiabatic process, and such a system is said to be adiabatically isolated. The assumption of an adiabatic process or isolation is frequently made when analyzing a system from the stand point of thermodynamics. For example, the compression of the gas within a cylinder of a diesel engine is assumed to occur so rapidly such that on the time scale of the compression process, little of the system's energy can be transferred out as heat. Even though the cylinders are not insulated and are quite conductive, that process is idealized to be adiabatic.

The assumption of adiabatic isolation is a useful one, and is often combined with other assumptions about a system so as to make the calculation of the system's behavior possible. Such assumptions are idealizations. The behavior of actual machines deviates from these idealizations, but the assumption of such "perfect" behavior are useful first approximations about how the real world works.