3. Conclusion

Turbomachines are obviously subject to the principle of conservation of energy limited to mechanics for those conveying an incompressible fluid, and to the more encompassing principles of thermodynamics for those whose working fluid is compressible.

The two principles of thermodynamics that govern their operation can be stated as follows: energy is conserved but degraded.

Energy is always conserved when it changes form. For example, the blades of a compressor receive a certain amount of mechanical energy from the drive shaft and transfer this same amount of energy to the exported gaseous fluid, in various forms and obviously first and foremost in the form of pressure.

To limit the size of the machines, the fluid is circulated at high speed, which generates losses in various forms: the energy is degraded, resulting...