What Is an Adiabatic Process?

The adiabatic process is a change process of an adiabatic system, that is, the process of no heat exchange between the system and the environment.

The state change process performed without heat exchange between the system and the outside world. The adiabatic process is a simplification and

When the equation of state of a system is known, it is easy to find its various equivalent process equations. But no state parameter remains the same during the adiabatic process, so it is necessary to find out what it is to observe according to the laws of thermodynamics

According to the equation of state of ideal gas and the equation of adiabatic process, the state parameter relationship obtained by simultaneous solution is:

with

The above relationship shows that when the gas in the system reversibly adiabaticly expands, p and T both decrease; when the gas in the system is adiabaticly compressed, both p and T increase.

Pv diagram and Ts diagram of adiabatic process

According to the adiabatic process equation, the adiabatic process is a high-order hyperbola in the pv diagram, while the reversible adiabatic process is a constant entropy process and a vertical line on the Ts diagram. As shown in the figure, 1-2 is an adiabatic expansion process, and 1-2 'is an adiabatic compression process. In the future, in order to distinguish between a reversible adiabatic process and an irreversible adiabatic process (with an increase in entropy), the reversible adiabatic process is called a constant entropy process. ^[1]