Modeling the f and j Characteristics of the Offset Strip Fin Array

New models for predicting the thermal-hydraulic characteristics of offset strip fin arrays are developed. These models are developed by combining the asymptotic behaviour for the laminar and turbulent wake regions. Models in these two regions are developed by considering the offset strip fin as an array of short ducts or channels. The proposed models are compared with published experimental data for nineteen configurations of the rectangular offset strip fin. Model predictions are within ± 20 percent for 96 percent of friction factor data and 82 percent for Colburn j factor data. Extension of the new models for offset strip fins having non-rectangular subchannels is also discussed.