Simple harmonic analysis of regenerators

A simple harmonic analysis of the performance of regenerators is described. Computer calculations based on the simple harmonic analysis run orders of magnitude faster than time-integration methods, with acceptably small reductions in accuracy. This simple harmonic analysis method is based on previous one-dimensional differential equations of heat and mass flow, with the additional assumption of steadystate operation and with the key approximations that only the magnitudes and phases of the fundamental components of time-dependent variables are of interest and that the instantaneous friction-factor and heat transfer coefficients are determined from the instantaneous velocity via steady-flow correlations. This permits a rapid computation scheme in which complex amplitudes of oscillatory variables are used, without numerical time integrations. The method is presented here using the Kays and London correlations for stacked-screen regenerators, but it can be used for any regenerator matrix for which steady friction-factor and heat transfer correlations exist.