Comparison of the DESSIM Model With a Finite Difference Solution for Rotary Desiccant Dehumidifiers

Abstract

A heuristic “pseudo-steady-state” model of the heat and mass transfer occurring in desiccant dehumidifiers, embodied in the program DESSIM, has been proposed as a conceptually and numerically simple analysis tool (Barlow, 1982). A comparison is made with a finite difference solution to determine the accuracy and limitations of the pseudo-steady-state model. The comparison indicates that the pseudo-steady-state model can produce accurate results of dehumidifier performance relative to the finite difference solution when used carefully, although at greater computational expense. Substitution of the finite difference solution into the overall DESSIM program results in a potentially accurate and useful analysis tool.