Abstract
An improved method for heat transfer calculation inside rough tubes is provided. The model has been obtained from a second assessment developed early by the authors on fluid flow in single-phase inside rough tubes. The proposed correlation has been verified by comparison with a total of 1666 experimental available data of 34 different fluids, including air, gases, water and organic liquids. The proposal model covers a validity range for Prandtl number ranging from 0.65 to 4.52?×10?^4, values of Reynolds number from 2.4×?10?^(3 )to 8.32×?10?^6, a range of relative roughness ranging from 5×?10?^(-2 )to 2×?10?^(-6 ), and viscosity ratio from 0.0048 to 181.5. The proposed model provides a good correlation for ?10?^4=Re and Re<?10?^4, with an average error of 18.3% for 70.4% of the data and 16.6% for 74.8% of the data, respectively. The method presents a satisfactory agreement with the experimental data in each interval evaluated; therefore, the model can be considerate accurate enough for practical application. At the present time, in the available technical literature, a method with similar characteristics is unknown.