116 results about "Heat transfer coefficient" patented technology

The heat transfer coefficient or film coefficient, or film effectiveness, in thermodynamics and in mechanics is the proportionality constant between the heat flux and the thermodynamic driving force for the flow of heat (i.e., the temperature difference, ΔT): The overall heat transfer rate for combined modes is usually expressed in terms of an overall conductance or heat transfer coefficient, U. In that case, the heat transfer rate is: Q=hA(T₂-T₁) where: A: surface area where the heat transfer takes place, m² T₂: temperature of the surrounding fluid, K T₁: temperature of the solid surface, K. The general definition of the heat transfer coefficient is: h=q/ΔT where: q: heat flux, W/m²; i.e., thermal power per unit area, q = dQ/dA h: heat transfer coefficient, W/(m²•K) ΔT: difference in temperature between the solid surface and surrounding fluid area, K It is used in calculating the heat transfer, typically by convection or phase transition between a fluid and a solid.