Modeling of heat transfer enhancement by wire, coil inserts using artificial neural network analysis

This study presents an application of artificial neural networks (ANNs) to characterize thermo-hydraulic behavior of helical wire coil inserts inside tube. An experimental study was carried out to investigate the effects of four types of wire coil inserts on heat transfer enhancement and pressure drop. The experimenal data sets were extracted from four wire coils which were tested within a geometrical range with helical pitch 0.156 < p/d(h) < 0.354 and wire diameter 0,027 < e/d(h) < 0.094. The investigation was conducted with transition and turbulent flow regimes with Reynolds numbers ranging from 4200 to 49,000. The experimental data sets have been utilized in training and validation of the ANN in order to predict the Nusselt numbers and friction factor inside tube with wire coil inserts, and the results were compared to the corresponding correlations. The mean relative errors (MIZE) between the predicted results are experimental data were found less than 1.79% for Nusselt numbers and less than 3.27% for friction factors. The performance of the ANN was found to be superior in comparison with corresponding power-lay regressions. Finally, using the ANN in order to predict the performance of thermal systems in engineering applications is recommended. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.