Download scientific diagram | Compressibility factor z versus 100/V, for several values of Pressure and 222 Temperature, for CO2. 223 224 The optimum placement of the compressor in the diagram of Figure 4 is achieved at 225 temperatures and pressures below the critical point. The increase of the temperature or 226 the pressure above the critical point leads to big changes in the compressibility factor. In 227 general, small changes in temperature and/or pressure around the critical point involves 228 big thermodynamic changes. This paper analyzes power cycles with the compressor 229 working in this region. We will call the region around the critical point "pericritical 230 region", where peri stands for "around" in Latin. 231 232 from publication: Thermodynamic mapping of power cycles working around the critical point | A new thermodynamic coefficient, called logarithmic factor of isobaric expansion, is defined for a better guidance in the cycle characterization of regenerative cycles working totally or partially at supercritical conditions. The logarithmic factor of isobaric expansion | Cycling, Thermodynamics and Work | ResearchGate, the professional network for scientists.