Effects of Corrugation Angle on Flow and Heat Transfer in Cross Corrugation Channels With Sinusoidal Waves

Fluid field and heat transfer in a cross-corrugated (CC) geometry with sinusoidal wavy plates have been investigated with laminar flow assumption. The 7 × 7 multiple channels configuration with six different corrugation intersection angles θ are studied. For air mass flow rates in the range of 50 ≤ Re ≤ 2000 and P/Hi = 2.2, average Nu and Fanning friction factor f are analyzed. Numerical results show that Fanning friction factors increase with corrugation intersection angle θ. But the Re of transition to turbulence decreases when θ > 90°. Moreover, the absence of a sharp transition is demonstrated for θ ≤ 90°. The distribution of local Nu becomes slightly flatter along the width when θ increases. The maximal Nu locates near the main flow trailing position and at the entrances of the neighborhood outflows, the minimum Nu locates at the contact points of top plate and bottom plate. Average Nu shows different variety with various ranges of corrugation intersection angle θ and Re, the maximum average Nu is obtained with 120° plate. Predictive correlations of f and Nu with Re have been carried out base on the numerical results. The sinusoidal wavy plates have a Nu which is about 6.5 times higher than that of a parallel-plate channel. And the concomitant f is about 54 times higher than that of the sinusoidal wavy plates. At last, the comprehensive assessment of the surfaces performance shows that the 30° plate surface has the optimal performance, while the one with 150° angle has the worst performance.