Overall Heat Transfer Coefficient

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Overall Heat Transfer Coefficient Thermodynamics

Related Resources:

• Overall Heat Transfer Coefficient - Heat Transfer
• Overall Heat Transfer Table Chart

In the case of combined heat transfer, it is common practice to relate the total rate of heat transfer (Q), the overall cross-sectional area for heat transfer (A_o), and the overall temperature difference (ΔT_o) using the overall heat transfer coefficient (U_o). The overall heat transfer coefficient combines the heat transfer coefficient of the two heat exchanger fluids and the thermal conductivity of the heat exchanger tubes. U_o is specific to the heat exchanger and the fluids that are used in the heat exchanger.˙

Q = U_oA_o ΔT_o

where: ˙

Q = the rate heat of transfer (Btu/hr)
U_o= the overall heat transfer coefficient (Btu/hr -ft² -^oF)
A_o= the overall cross-sectional area for heat transfer (ft²)
ΔT_o= the overall temperature difference (^oF)