TR | Tons of refrigeration | |

h | Enthalpy of Refrigerant in gaseous phase | |

R134a | 1,1,1,2-tetraflouroethane | |

R1270 | Propylene | |

R125 | 1,1,12,2-pentaflouroethane | |

R152a | 1,1-diflouroethane | |

T | Discharge Temperature | |

R | Compression ratio | |

g | Ratio of heat capacities | |

T | Suction temperature | |

P | Pressure | |

H | Enthalpy | |

U | Internal energy | |

V | Volume | |

Rev | Reversible | |

h | Efficiency | |

W | Compressor work | |

W | Real work | |

$\dot{m}$ | Mass flow rate | |

D | Change | |

C | Specific heat capacity t constant pressure | |

C | Specific heat capacity t constant volume | |

R | Universal gas constant | |

Isen | Isentropic | |

M | Mass flow of refrigerant | |

Q | Evaporator duty | |

Q | Condenser duty | |

S | Enthropy | |

TXV | Thermal Expansion valve | |

U | Coefficient heat transfer | |

A | Area | |

COP | Coefficient of performance | |

T/h | Tones per hour | |

X | Quality of refrigerant | |

Cv | Valve flow Coefficient | |

N | Number of tubes | |

1, 2, 3, 4 | States on P-h diagram | |

ρ | Density | |

C | Cyclohexane | |