Heat Exchanger Duty Calculator — Formula
## Heat Exchanger Duty
The thermal duty Q is the rate of heat transfer between the hot and cold streams. It is calculated from the energy balance on one side of the exchanger.
### Formula
**Q = m × Cp × |T_in - T_out|**
where m is the mass flow rate, Cp is the specific heat capacity, and the temperature difference is the change experienced by the fluid. At steady state, the duty calculated on the hot side must equal the cold side (energy balance).
The thermal duty Q is the rate of heat transfer between the hot and cold streams. It is calculated from the energy balance on one side of the exchanger.
### Formula
**Q = m × Cp × |T_in - T_out|**
where m is the mass flow rate, Cp is the specific heat capacity, and the temperature difference is the change experienced by the fluid. At steady state, the duty calculated on the hot side must equal the cold side (energy balance).
Exemplo Resolvido
Water flowing at 5 kg/s is cooled from 80°C to 40°C.
- delta_T = |80 - 40| = 40°C
- Q = 5 × 4.18 × 40 = 836 kW
- In BTU/h: 836 × 3412.14 = 2,852,549 BTU/h