A first principles approach to develop a dynamic model of electrochemical capacitors

As an aid to improving the dynamic response of the steam reformer, a dynamic model is developed to provide preliminary characterizations of the major constraints that limit the ability of a reformer to respond to the varying output requirements occurring in vehicular applications. This model is a first principles model that identifies important physical parameters in the steam reformer. The model is then incorporated into a design optimization process, where minimum steam reformer response time is specified as the objective function. This tool is shown to have the potential to be a powerful means of determining the values of the steam reformer design parameters that yield the fastest response time to a step input in hydrogen demand for a given set of initial conditions. A more extensive application of this methodology, yielding steam reformer design recommendations, is contained in a related publication.

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Dynamic simulation of a thermomechanical pulp refiner

Nordic Pulp & Paper Research Journal ◽

10.3183/npprj-1997-12-04-p270-275 ◽

1997 ◽

Vol 12 (4) ◽

pp. 270-275

Author(s):

Alexander Horch ◽

Alf J. lsaksson ◽

Bruce J. Allison ◽

Anders Karlström ◽

Lennart Nilsson

Keyword(s):

Temperature Profile ◽

Dynamic Model ◽

Dynamic Simulation ◽

Water Flow ◽

First Principles ◽

Black Box ◽

Thermomechanical Pulp ◽

Screw Speed ◽

Dilution Water ◽

Motor Load

Abstract The aim of this paper is to describe a model for dynamic simulation of a TMP refiner. The temperature profile along the radius of the refiner, outlet consistency and motor load are considered as outputs of the simulation, whereas the chip screw speed and dilution water flow setpoints are the inputs. The dynamic model of the refiner, as such, has been derived from first principles. The motor load and input dynamics, however, are based on black-box identifications. The model has been implemented in MATLABISIMULINK. Simulations are compared to corresponding data from experiments with the refiner.

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FIRST PRINCIPLES, UNSTRUCTURED, DYNAMIC MODEL FOR REGULATING CO2 AND pH IN BICARBONATE BUFFERED PERFUSION BIOREACTOR

10.23860/thesis-airan-ashish-gaurav-2013 ◽

2013 ◽

Author(s):

◽

Ashish Gaurav Airan

Keyword(s):

Dynamic Model ◽

First Principles ◽

Perfusion Bioreactor

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Short-term volume and turgor regulation in yeast

Essays in Biochemistry ◽

10.1042/bse0450147 ◽

2008 ◽

Vol 45 ◽

pp. 147-160 ◽

Cited By ~ 12

Author(s):

Jörg Schaber ◽

Edda Klipp

Keyword(s):

Dynamic Model ◽

Volume Change ◽

Volume Regulation ◽

Time Course ◽

Osmotic Shock ◽

Intracellular Concentration ◽

Short Term ◽

Hydrodynamic Property ◽

Turgor Regulation ◽

Thermodynamic Framework

Volume is a highly regulated property of cells, because it critically affects intracellular concentration. In the present chapter, we focus on the short-term volume regulation in yeast as a consequence of a shift in extracellular osmotic conditions. We review a basic thermodynamic framework to model volume and solute flows. In addition, we try to select a model for turgor, which is an important hydrodynamic property, especially in walled cells. Finally, we demonstrate the validity of the presented approach by fitting the dynamic model to a time course of volume change upon osmotic shock in yeast.

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