Condensation of Steam - Heat Transfer
Heat transfer when steam condensates.
The heat released when condensing steam can be expressed as
Q = he Ms (1)
where
Q = quantity of heat released (kJ, Btu)
Ms = mass of condensing steam (kg, lb)
he = specific evaporation enthalpy of steam (kJ/kg, Btu/lb)
The heat transfer rate - or power - in a condensing steam flow can be expressed as
q = he ms (2)
where
q = heat transfer (kW, Btu/h)
ms = steam flow rate (kg/s, lb/h)
Example - Heat released when Condensing Steam
5 kg of steam with atmospheric pressure, temperature 100 oC and evaporation enthalpy 2257 kJ/kg is condensated. The heat transfer can be calculated as
Q = (2257 kJ/kg) (5 kg)
= 11285 kJ
Example - Heat Transfer Rate - or Power - in a Condensing Steam Flow
The heat transfer rate in a condensing steam flow rate of 8 kg/h (0.0022 kg/s), atmospheric pressure and temperature 100 oC - can be calculated as
q = (2257 kJ/kg) (0.0022 kg/s)
= 5 kJ/s (kW)
