TRANSIENT THERMAL-ANALYSIS OF A SPHERICAL LIQUID STORAGE TANK DURING CHARGING

A spherical liquid thermal storage tank made up of two concentric spheres is modeled using the transient one-dimensional energy equation in the spherical coordinates. A numerical solution is obtained for the modeling partial differential equation using a fully implicit finite difference method. The solution is used to study the transient thermal behavior of the spherical liquid tank during the charging mode, which is presented in terms of the spatial and temporal temperature distributions inside the liquid tank, as well as the variation of energy stored with time. The effects of various design and operating parameters such as the tank size, inlet and ambient temperatures, and inlet mass flux on the thermal storage characteristics of the tank are fully investigated. Further, the thermal storage performance of the spherical tank is compared with that of an equal volume cylindrical packed bed under the same operating conditions. © 1990.