Title :
Diffusion systems: stability, modeling, and identification
Author :
Pintelon, Rik ; Schoukens, Johan ; Pauwels, Laurence ; Van Gheem, Els
Author_Institution :
Dept. of Electr. Meas., Vrije Univ. Brussels, Belgium
Abstract :
Physical phenomena governed by diffusion (for example, mass or heat transfer) are often better described by rational transfer function models G(√s) in √s than by rational forms G(s) in the Laplace variable s. A striking difference between both models is that the impulse response of G(s) decreases exponentially to zero, while that of G(√s) decreases algebraically to zero. Hence, transient effects in diffusion phenomena may last long before they can be neglected in, for example, frequency response function measurements. This paper presents an extended transfer function model and an identification algorithm that can handle the slowly decaying transients and, as a consequence, (significantly) reduce the experiment time.
Keywords :
diffusion; frequency response; identification; partial differential equations; rational functions; transfer functions; transient response; decaying transients; diffusion phenomena; diffusion systems; fractional derivative; frequency response function measurements; identification algorithm; impulse response; system identification; transfer function models; transient effects; Boundary conditions; Differential equations; Frequency measurement; Frequency response; Noise level; Noise measurement; Partial differential equations; Stability; Time measurement; Transfer functions; Diffusion; fractional derivative; frequency domain; impulse response; system identification;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
DOI :
10.1109/TIM.2005.853351