Book Description

In recent years there has been an increased emphasis being placed on the study of natural convection in various systems. The majority of studies have been concerned with concentric geometries. The studies oriented toward eccentric geometries have been very few and very specialized. The major emphasis of the studies have been the derivation of correlation equations used to describe the Nusselt numbers obtained in isothermal boundary systems. There is little reported research dealing with the problem of natural convection in an eccentric geometry subject to a free convection boundary. This study deals directly with a horizontal eccentric annuli geometry subject to the free convection outer boundary. A set of experimental measurements have been taken for various fluids and various eccentric geometries. The fluids included in this study include water, mercury, and glycerin. These fluids span a Rayleigh number range from approximately 25 to slightly in excess of 108. The results of these experiments have been correlated in a manner that allows the direct prediction of the maximum temperature distribution of the outer shell for the eccentric annular geometry. The only information required for the use of the equations may be obtained from the corresponding concentric geometry. The results of using the correlation equations to predict the temperature profiles occurring in the various experiments show a maximum deviation at any particular point of approximately 2.0% with an average deviation of approximately 0.5%. In addition the study investigates the feasibility of using a standard finite-difference code to calculate the observed temperature profiles. A sensitivity study is performed to determine the required accuracy of the heat transfer coefficients for the various surfaces to be input into the code.