Definition of L/G ratio
where,
L/G = liquid to gas mass flow ratio (kg/kg)
T1 = hot water temperature (0C
T2 = cold water temperature (0C)
h2 = enthalpy of air-water vapor mixture at exhaust wet-bulb temperature
h1 = enthalpy of air-water vapor mixture at inlet wet-bulb temperature
Liquid/Gas
(L/G) ratio, of a cooling tower is the ratio between the water and the air mass
flow rates. Against design values, seasonal variations require adjustment and
tuning of water and air flow rates to get the best cooling tower effectiveness
through measures like water box loading changes, blade angle adjustments.
Thermodynamics also dictate that the heat removed from the water must
be equal to
the heat absorbed by the surrounding air:
L ( T1-T2 ) = G ( h2-h1 )
L/G = (h2-h1)/(T1-T2)
L/G = liquid to gas mass flow ratio (kg/kg)
T1 = hot water temperature (0C
T2 = cold water temperature (0C)
h2 = enthalpy of air-water vapor mixture at exhaust wet-bulb temperature
h1 = enthalpy of air-water vapor mixture at inlet wet-bulb temperature