Periodic forcing of the CSTR: An Application of the generalized II‐criterion

Abstract

Nonlinearities give the opportunity to influence the time average performance of a system by periodic forcing of external parameters. In this article, this concept is applied to the following reactions occurring in a continuous stirred tank reactor:

Bifurcation analysis of two continuous membrane fermentor configurations for producing ethanol

“…When the fermentors are connected in series and the ÿrst fermentor has oscillatory (either periodic or chaotic) behavior then the output of this ÿrst fermentor becomes the non-autonomous input to the second fermentor. Various oscillating, non-autonomous feed inputs have been tried in biological and chemical processes to improve the conversion, yield and productivity of the process (Douglas and Rippin, 1966;Douglas, 1972;Crooke et al, 1980;Sterman and Ydstie, 1991;Henson and Seborg, 1992;Yang and Su, 1993;Balakrishnan and Yang, 2002).…”

Pulsed activation in heterogeneous catalysis

“…Moreover they have been set in such a way that they form a system which responds favorably to pulsed operation. Specifically, for this system that means that the activation energy for the desired reaction should be higher than that of the undesired reaction (E 3 > E 2 ) to make periodic operation beneficial, as was discussed in section 3.1 and in reference [41]. In practice this means that the surface reaction should be more temperature dependent than the desorption of the reactant.…”

“…Sterman and Ydstie applied the Π-criterion to several basic reaction systems with two competing reactions [41]. They showed that periodic temperature forcing always outperforms the best steady state operation if the activation energy for the desired reaction is higher than that of the undesired reaction.…”

Polyoptimal Multiperiodic Control of Complex Systems with Inventory Couplings Via the Ideal Point Evolutionary Algorithm

“…Step 2: Using the π-test ( (Bernstein & Gilbert, 1980;Sterman & Ydstie, 1991)) evaluate the intervals [τ i− , τ i+ ] of period values guaranteeing the local improvement of the subsystems objective functions by the periodic operation, and choose…”