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Computational fluid dynamics simulation of chemically reacting gas flows through microfibrous materialsDuggirala, Ravi Kumar, Roy, Christopher. J., January 2008 (has links) (PDF)
Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 195).
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Radial heat transfer studies in low tube to particle diameter ratio fixed bed reactorsLeising, Guillaume M. January 2005 (has links)
Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: fixed bed; heat transfer. Includes bibliographical references (p. 67-71).
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Chaotic hydrodynamics of large and small circulating fluidized bedsZijerveld, R. C. January 1900 (has links)
Thesis (doctoral)--Techische Universiteit Delft, 1998. / Includes bibliographical references.
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Kinetic bounds on attainability in the reactor synthesis problemAbraham, Thomas Kannankara, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xvi, 190 p.; also includes graphics (some col.). Includes bibliographical references (p. 182-190). Available online via OhioLINK's ETD Center
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Reaction kinetics and reactor modelling in the design of catalytic reactors for automotive exhaust gas abatementAhola, J. (Juha) 10 February 2009 (has links)
Abstract
The tightening environmental legislation and technological development in automotive engineering form a challenge in reactor design of catalytic reactors for automotive exhaust gas abatement. The catalytic reactor is the heart of the exhaust aftertreatment processes, but it can be seen also just as one subsidiary part of vehicles.
The aim of this work is to reveal applicable kinetic models to predict behaviour of the particular catalysts and to establish guidelines for modelling procedures and experimentation facilitating catalytic reactor design, especially in the field of automotive exhaust gas abatement.
The studies in this thesis include catalyst kinetics with synthetic exhaust gas composition in stoichiometric and net oxidative conditions, DRIFT measurements, and the warm-up of three-way catalysts in real conditions.
Knowledge on surface concentrations facilitates kinetic model construction and discrimination. For example, identification of even semi-quantitative surface concentrations may lead to a successful falsification of incorrect kinetic model candidates. Especially, that is clearly seen in cases where models predict the same kind of gas phase behaviour but different kinds of surface concentration profiles.
The transient kinetic experiments could give a hint on predominant reaction mechanism, support quantifying of the adsorption capacity and reveal the impact of surface phenomena on reactor dynamics.
The level of model complexity should be adapted depending on the purpose of the model. For example, it is mostly convenient for reactor design purposes to perceive only one type of active sites even in a case of mechanical mixture of different catalytic materials; whereas the optimisation of catalyst content demands the management of every prominent site type separately. Or, when a catalytic material has been selected, the stationary kinetic model is, in most cases, adequate for the catalytic converter design and structural optimization for warm-up conditions.
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Design of decoupling control and time-delay compensation for a CFSTRChen, Liang January 1990 (has links)
This thesis is concerned with the design of a decoupling compensator and a time-delay compensator for a nonisothermal continuous flow stirred tank reactor (CFSTR). An expression for the analysis of interaction of the two-variable CFSTR was theoretically derived by using the relative gain method (RGM). For the purpose of improving the stability of the decoupling control system, undercompensation for a decoupled CFSTR system was suggested and the robustness test of such undercompensation decoupler to the modelling error was studied. On the other hand, the proposed time-delay compensation method, unlike conventional Smith's scheme, can rely on the basic property of gain-invariant time-delay. The stability of this time-delay compensation method is not affected by the CFSTR control system time-variant time-delay, while its compensation structure has the same features as the Smith compensator.
The design of a decoupler and that of a time-delay compensator are independent of each other. All compensation structures are physically realizable.
The theoretical results are supported by simulation. Simulation results for a CFSTR demonstrate that the undercompensation decoupling control can tolerate a relatively wide modelling error and reduce the sensitivity of the CFSTR process to parameter variations and unwanted disturbances. Also, simulation results show that the proposed time-delay compensator can provide an improvement over the conventional Smith compensator. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
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Control and Optimization of Chemical Reactors with Model-free Deep Reinforcement LearningAlhazmi, Khalid 07 1900 (has links)
Abstract: Model-based control and optimization is the predominant paradigm in process systems
engineering. The performance of model-based methods, however, rely heavily
on the accuracy of the process model, which declines over the operation cycle due to
various causes, such as catalyst deactivation, equipment aging, feedstock variability,
and others. This work aims to tackle this challenge by considering two alternative
approaches. The first approach replaces existing control and optimization methods
with model-free reinforcement learning (RL). We apply a state-of-the-art reinforcement
learning algorithm to a network of reactions, evaluate the performance of the
RL controller in terms of setpoint tracking, disturbance rejection, and robustness to
parameter uncertainties, and optimize the reward function to achieve the desired control
and optimization performance. The second approach presents a novel framework
for integrating Economic Model Predictive Control (EMPC) and RL for online model
parameters estimation. In this framework, EMPC optimally operates the closed-loop
system while maintaining closed-loop stability and recursive feasibility. At the same
time, the RL agent continuously compares the measured state of the process with the
model’s predictions, and modifies the model parameters accordingly to optimize the
process. The performance of the proposed framework is illustrated on a network of
reactions with challenging dynamics and practical significance.
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The effect of protein structural configuration on the free enzyme kinetic behavior of urease /Lencki, Robert W. J. January 1987 (has links)
No description available.
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Turbulent mixing with chemical reaction /McKelvey, Kenneth Norwood January 1968 (has links)
No description available.
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Dynamic response of a packed, tubular reactorWashington, James MacKnight January 1964 (has links)
Master of Science
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