Heat transfer and pressure drop correlations for laminar flow in an in-line and staggered array of circular cylinders

Enhanced heat transfer surfaces based on cylindrically shaped pin fins with wire diameters in the range of 100 µm were analyzed. The design is based on a high pin length to diameter ratio in the range of 20–100. Correlations for thermal and fluid dynamic characteristics of these fine wire structures are not available in literature. An in-line and staggered arrangement of pins were simulated for a variety of operational and geometrical conditions with a two-dimensional computational thermal and fluid dynamics model. Correlations for Nusselt number and friction factor with respect to Reynolds number and geometry were derived thereby. Reynolds numbers based on the wire diameter are in the range of 3–60. The correlations for the Nusselt number and friction factor can predict 93% and 97% of the simulated data within ±10%.