ANALYTICAL SOLUTIONS FOR LAMINAR FULLY-DEVELOPED FLOWS IN DOUBLE-SINESHAPED DUCTS

Fully developed, constant property, laminar flows in double-sine shape d ducts are considered. This cross section represents a limiting inter -plate channel geometry in plate heat exchangers. Accurate analytical solutions based on the Galerkin integral method are presented. Heat tr ansfer with both T and H1 thermal boundary conditions is analyzed; the y simulate the most fundamental practical heating/cooling applications . Velocity and temperature distributions, along with fRe, Nu(T), and N u(H1) results for flows in double-sine ducts of different aspect ratio s (1/8 less than or equal to gamma less than or equal to 8) are presen ted. Effects of the relative cross-sectional geometry and thermal boun dary conditions are delineated. A comparison of the thermal-hydraulic performance with that of other compact channel geometries is made. The results suggest an optimum (Nu/fRe) performance in a double-sine duct of aspect ratio near unity.