New Bounded Skew Central Difference Scheme, Part Ii: Application to Natural Convection in an Eccentric Annulus

The bounded skew central difference scheme (NVF SCDS) [1] is used to study numerically the combined effect of vertical (εy) and horizontal (εx) eccentricities on natural convection in an annubis between a heated horizontal cylinder and its square enclosure. Four Rayleigh numbers (Ra = 103, 104, 105;, and 106), three aspect ratios (R/L = 0.1, 0.2, and 0.3), and eccentricity values ranging from —0.3 to 0.3 art considered. At constant enclosure aspect ratio, the total heal transfer increases with increasing Rayleigh number. For constant Raykigh-number values, convection contribution to total heat transfer decreases with increasing values of R/L. For conduction-dominated flows, heat transfer increases with increasing |εy| and / or |εx|. For convection-dominated flows, heat transfer increases with decreasing εy for εy < 0, decreases with increasing εy for εy > 0, and decreases with decreasing εy for εx < 0. For the cast when conduction and convection are of equal importance, there is a critical εx for which the total heat transfer is minimum.