Next, a great deal can be computed for isentropic processes of an ideal gas.

For a reversible process, this is identical to an isentropic process.

It can be determined for an isentropic process that the second law of thermodynamics results in the following:

An isentropic process occurs at a constant entropy.

It can be proven that any reversible adiabatic process is an isentropic process.

Thus an irreversible isentropic process is not adiabatic.

Any adiabatic process that is also reversible is called an isentropic process.

It is possible to estimate the temperature rise across a supercharger by modeling it as an isentropic process.

Most turbo machines are efficient to a certain degree and can be approximated to undergo isentropic process in the stage.

For isentropic processes, the Cauchy number may be expressed in terms of Mach number.

For a reversible isentropic process, there is no transfer of heat energy and therefore the process is also adiabatic.

Isentropic process: a reversible adiabatic process occurs at a constant entropy, but is a fictional idealization.

A vertical line in the h-s chart means an isentropic process and an horizontal line means an isenthalpic process.

In the original 19th-century Brayton engine, ambient air is drawn into a piston compressor, where it is compression; ideally an isentropic process.

Where 1 to 3ss in Figure 1 represents the isentropic process beginning from stator inlet at 1 to rotor outlet at 3.

An isentropic process is depicted as a vertical line on a T-s diagram, whereas an isothermal process is a horizontal line.

This is a near isentropic process and the corresponding temperature reduction leads to condensation of target components of the mixed feed gas which form a fine mist.

Since temperature is thermodynamically conjugate to entropy, the isothermal process is conjugate to the isentropic process, and therefore to a reversible adiabatic process.

If we assume dry air, and ideal gas equation of state and an isentropic process, we have enough information to define the pressure ratio and efficiency for this one point.

Since the Otto cycle is an isentropic process the isentropic equations of ideal gases and the constant pressure/volume relations can be used to yield Equations 3 & 4.

Since, by the second law of thermodynamics, for a reversible process (where T is temperature and S is entropy), a reversible adiabatic process is also an isentropic process ().

The isentropic processes are impermeable to heat: heat flows into the loop through the left expanding isobaric process and some of it flows back out through the right depressurizing process, and the heat that remains does the work.

An ideal steam turbine is considered to be an isentropic process, or constant entropy process, in which the entropy of the steam entering the turbine is equal to the entropy of the steam leaving the turbine.

The heated (by compression), pressurized air and fuel mixture is then ignited in an expansion cylinder and energy is released, causing the heated air and combustion products to expand through a piston/cylinder; another ideally isentropic process.

In order to achieve a near thermodynamic reversible process so that most of the energy is saved in the system and can be retrieved, and losses are kept negligible, a near reversible isothermal process or an isentropic process is desired.