A new method to predict convective heat transfer in a tube with twisted tape inserts for turbulent flow

The article presents a new approach in predicting the convective heat transfer coefficient in a tube with twisted tape inserts of different pitch to diameter ratios. A modification is proposed to the classical van Driest eddy diffusivity expression to respond to the case of swirl flow generated by the tape inserts. The universal constant K in the relationship is found to be a function of pitch to diameter ratio of the tape and Reynolds number of the flow in the tube. The proposed analysis is compared with various correlations available in the literature showing reasonable agreement between them. (C) 2002 Editions scientifiques et medicales Elsevier SAS. All rights reserved.