log p,h Refrigeration Cycle

Refrigeration cycle multi-tool for DX air coolers and chillers, air- or water-cooled, with heat recovery. Properties from CoolProp

Sample values, replace with your own measurements
log p,h chartHover over the chart to read a state
Measured cycle 1-2-3-4 Isentropic compression 1 → 2s Bubble and dew line Isotherms Isentropes
System
Refrigerant circuit
Evaporator · air
Condenser · air
Power & ambient

State points

Pointp bar abst °Ch kJ/kgs kJ/kgK

Refrigerant circuit

Heat exchangers & energy balance

Assessment

    Properties: CoolProp 8.0 (IIR reference state, h = 200 kJ/kg and s = 1 kJ/kgK for saturated liquid at 0 °C; R717 uses its own reference state), stored as tables and interpolated in ln p and superheat. Subcooled liquid is approximated with the enthalpy of saturated liquid at the same temperature. For zeotropic blends (R407C, R404A), superheat refers to the dew line and subcooling to the bubble line. Secondary side: water capacity Q = V·ρ·cp·ΔT with properties at about 10 °C (water 4.19, ethylene glycol 30 % 3.70, propylene glycol 30 % 3.88 kJ/kgK); air capacity from moist air (evaporator with RH via enthalpy, otherwise sensible only). Refrigerant mass flow follows from Q₀ / q₀; heat recovery is modelled as a desuperheater right after the compressor (point 2H). Measured pipe surface temperatures (strap-on sensors) usually read slightly below the fluid temperature, especially on the discharge line.