Heat Transfer
Heat Duty Calculator
Heat duty is the rate of energy transfer required to heat or cool a process stream. For continuous flow, it is the product of mass flow rate, specific heat capacity, and temperature change. This calculator also supports a batch mode for fixed-mass heating or cooling. You must supply the specific heat capacity — no material lookup is performed.
TypeInteractive calculator — separate from unit conversions
Calculator
Result
Heat duty (power)83.68 kW
Formulas
Continuous heat duty (power)
Q̇ = ṁ × Cp × ΔT
Batch heat duty (energy)
Q = m × Cp × ΔT
Diagram
Worked example
A stream flows at 2 kg/s with Cp = 4.184 kJ/(kg·K) and is heated by 10 K. What is the continuous heat duty?
- 01Q̇ = ṁ × Cp × ΔT
- 02Q̇ = 2 × 4.184 × 10 (all in SI: kg/s, kJ/(kg·K), K)
- 03Q̇ = 83.68 kW
Result
The continuous heat duty is 83.68 kW.
FAQ
Does this calculator look up Cp for water, air, or steam?
No. You must supply the specific heat capacity. No material property lookup is performed.
Is this a heat exchanger sizing calculator?
No. This calculator computes heat duty only. Heat exchanger sizing (UA, LMTD, NTU) is not implemented.
Does this handle phase change or latent heat?
No. This is a sensible-heat calculator only. Latent heat and phase-change calculations are excluded.
What is the difference between continuous and batch mode?
Continuous mode uses mass flow rate (kg/s) and produces power (kW). Batch mode uses total mass (kg) and produces energy (kJ).