免费换热器热负荷计算器
计算换热器的传热功率(热负荷)。
Heat Duty (Q)
836.00 kW
Heat Duty (Q) vs Mass Flow Rate (m)
公式
## 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).
计算示例
Water flowing at 5 kg/s is cooled from 80°C to 40°C.
- 01delta_T = |80 - 40| = 40°C
- 02Q = 5 × 4.18 × 40 = 836 kW
- 03In BTU/h: 836 × 3412.14 = 2,852,549 BTU/h
常见问题
What is a typical heat exchanger duty range?
Small process heaters may handle 10-100 kW, while large industrial exchangers can handle 1-100 MW. Power plant condensers may handle 500+ MW of thermal duty.
How does phase change affect the calculation?
If the fluid undergoes a phase change (boiling or condensation), you must add the latent heat: Q = m × h_fg, where h_fg is the latent heat of vaporization. The sensible heat formula shown here only applies to single-phase fluids.
What if I know the cold side conditions?
The duty must be the same on both sides (energy conservation). Calculate Q from whichever side you have complete data for. You can then find the unknown temperature or flow rate on the other side.
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