Year: 1978
Type: report
Abstract: A multidimensional, time-dependent model of the thermocline degradation in a packed bed thermal storage tank is presented. In earlier reports a one-dimensional model, incorporating the effects of heat losses out the ends of the tank, was solved analytically using both separation of variables and transform methods. The multidimensional analysis presented here includes the additional effects of heat losses out of the sides of the tank for the types of boundary conditions of greatest interest, and is thus a more realistic model of the problem. The technique used to solve the coupled pair of partial differential equations describing the degradation of the thermocline is based on a vectorized separation of variables approach. Assuming cylindrical geometry, the analysis leads to separate eigenvalue problems for the radial, angular, and axial spatial dependencies of the fluid and solid temperatures in the bed. The eigenvalues are readily calculated and the corresponding eigenfunctions are shown to form a complete set of spatial basis functions for the solution space. The applicability of the method is illustrated by an example and important conclusions are drawn from the results.
DOI: 10.2172/5128218
Author: S Margolis
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
Funder: U.S. Department of Energy
OpenAlex ID: W4234022591