COP of Double effect chiller

[nasir]

dears all,
please let me know how i can determine the cop of double effect, gas fired absorption chiller usinf lithium bromide as an absorbant and water as a referigerant? what parametres are required to determine the cop, please give me the formulae of calculating the cop, thank
Regards
nasir

[Ravi]

The basic definition of COP is same whether it is a vapor refrigeration cycle or absorption cycle and takes the equation (Refrigrating Effect/Power Input). Refrigerating Effect is the heat rejected to (or absorbed by) chilled water and can be calculated by mxCpxdT (if you know the mass flowrate of water). Power output can be calculated by m1xNCV, where m1 is the mass flowrate of fuel burned and NCV is the net calorific value of the fuel (or LHV - lower heating value). A precise calculation sould include power consumption by absorbent, refrigerant and vacuum pumps.

Check for similarity in units while performing the calculation.