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H-infinity control for continuous stirred tank reactor based on Takagi-Sugeno fuzzy bilinear models


控制理论与应用 , 2012,
Abstract: This paper is concerned with the H-infinity control for a class of continuous stirred tank reactor (CSTR) systems, in which the nonlinear dynamics are described by Takagi-Sugeno fuzzy bilinear models. By introducing two free matrix variables, we derive a new sufficient condition, in terms of linear matrix inequalities, of the global stability with a prescribed H-infinity performance level for the closed-loop fuzzy bilinear systems. The controller design method is also given. Simulation results of a CSTR system illustrate the effectiveness of the design method.
DYNA , 2007,
Abstract: in this paper a fuzzy model based on dynamic takagi-sugeno-kang framework of a continuous stirred tank reactor (cstr) with exothermic fist order chemical reaction is carried out. from experimental data base obtained through real process simulation for input and output variables, the training and checking files of the fuzzy model were developed. theses files allow us to carried out the fuzzy model by mean of the anfis tool of matlab. the model obtained allow us to predict the system out put with a very small prediction error for that reason this model is very important to design a nonlinear predictive control based fuzzy model to this process in future research stages.
Modeling of Coupled-Tank System Using Fuzzy Takagi-Sugeno Model  [PDF]
Aries Subiantoro
Makara Seri Teknologi , 2006,
Abstract: This paper describes modeling of coupledtank system based on data measurement using fuzzy Takagi-Sugeno model. The fuzzy clustering method of Gustafson- Kessel algorithm is used to classify input-output data into several clusters based on distance similarity of a member of input-output data from center of cluster. The formed clusters are projected orthonormally into each linguistic variables of premise part to determine membership function of fuzzy Takagi-Sugeno model. By estimating data in each cluster, the consequent parameters of fuzzy Takagi-Sugeno model are calculated using weighted least-squares method. The resulted fuzzy Takagi-Sugeno model is validated by using model performance parameters variance-accounted-for (VAF) and root mean square (RMS) as performance indicators. The simulation results show that the fuzzy Takagi-Sugeno model is able to mimic nonlinear characteristic of coupled-tank system with good value of model performance indicators.
Digital Control of a Continuous Stirred Tank Reactor
M. P. Di Ciccio,M. Bottini,P. Pepe
Mathematical Problems in Engineering , 2011, DOI: 10.1155/2011/439785
Abstract: We project a novel digital control law for continuous stirred tank reactors, based on sampled measures of temperatures and reactant concentration, as it happens in practice. The methodology of relative degree preservation under sampling is used. It is proved that a suitably approximated sampled system, obtained by Taylor series expansion and truncation, in closed loop with the projected control law, is asymptotically stable, provided that a condition on the sampling period is verified. Such condition allows for values of the sampling period larger than necessary in practical implementation with usual technology. Many simulations show the high performance of the proposed digital control law.
Modified Mathematical Model For Neutralization System In Stirred Tank Reactor  [cached]
Ahmmed Saadi Ibrehem
Bulletin of Chemical Reaction Engineering & Catalysis , 2011, DOI: 10.9767/bcrec.6.1.825.47-52
Abstract: A modified model for the neutralization process of Stirred Tank Reactors (CSTR) reactor is presented in this study. The model accounts for the effect of strong acid [HCL] flowrate and strong base [NaOH] flowrate with the ionic concentrations of [Cl-] and [Na+] on the Ph of the system. In this work, the effect of important reactor parameters such as ionic concentrations and acid and base flowrates on the dynamic behavior of the CSTR is investigated and the behavior of mathematical model is compared with the reported models for the McAvoy model and Jutila model. Moreover, the results of the model are compared with the experimental data in terms of pH dynamic study. A good agreement is observed between our model prediction and the actual plant data. 2011 BCREC UNDIP. All rights reserved (Received: 1st March 2011, Revised: 28th March 2011; Accepted: 7th April 2011) [How to Cite: A.S. Ibrehem. (2011). Modified Mathematical Model For Neutralization System In Stirred Tank Reactor. Bulletin of Chemical Reaction Engineering & Catalysis, 6(1): 47-52. doi:10.9767/bcrec.6.1.825.47-52] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.6.1.825.47-52 ] | View in
Modeling of organic pollutant destruction in a stirred tank reactor by ozonation
Modeling of organic pollutant destruction in a stirred-tank reactor by ozonation

,YANG Zhuo-ru,CHEN Huan-qin,KUO C.H.,ZAPPI E.M

环境科学学报(英文版) , 2001,
Abstract: Destruction of organic contaminants in water by ozonation is a gas liquid process which involves ozone mass transfer and fast irreversible chemical reactions. Ozonation reactor design and process optimizing require the modeling of the gas liquid interactions within the reactor. In this paper a theoretical model combining the fluid dynamic and reaction kinetic parameters is proposed for predicting the destruction rates of organic pollutants in a semi batch stirred tank reactor by ozonation. A simple expression for the enhancement factor as our previous work has been applied to evaluate the chemical mass transfer coefficient in ozone absorption. 2,4 dichlorophenol (2,4 DCP) and 2,6 DCP or their mixture are chosen as the model compounds for simulating, and the predicted DCP concentrations are compared with some measured data.
The Stirred Tank Reactor Polymer Electrolyte Membrane Fuel Cell  [PDF]
Jay Benziger,E. Chia,E. Karnas,J. Moxley,C. Teuscher,I. G. Kevrekidis
Physics , 2003,
Abstract: The design and operation of a differential Polymer Electrolyte Membrane (PEM) fuel cell is described. The fuel cell design is based on coupled Stirred Tank Reactors (STR); the gas phase in each reactor compartment was well mixed. The characteristic times for reactant flow, gas phase diffusion and reaction were chosen so that the gas compositions at both the anode and cathode are uniform. The STR PEM fuel cell is one-dimensional; the only spatial gradients are transverse to the membrane. The STR PEM fuel cell was employed to examine fuel cell start- up, and its dynamic responses to changes in load, temperature and reactant flow rates. Multiple time scales in systems response are found to correspond to water absorption by the membrane, water transport through the membrane and stress-related mechanical changes of the membrane.
Phenol Degradation: Numerical Simulation in a Stirred Tank Electrochemical Reactor  [PDF]
Regalado-Mendez Alejandro,Peralta-Reyes Ever,Velazquez-Manzanares Miguel
International Journal of Computer Science & Information Technology , 2010,
Abstract: In this work, phenol degradation of wastewater in a stirred tank chemical reactor was numerically simulated. The effect of the applied current density (I/A), changes in the concentration of dissolved O2and initial concentration of Fe2+ ions were studied. The operation conditions were 25°C, pH = 2.5, with 1000 mM phenol feed concentration at 1 atm of pressure. The results show that the phenol removal achieved was 78.97%, 84.2%, 97.0% and 99.8% for values of I/A of 0.3, 0.32, 0.37 and 0.4 mA cm-2, respectively. For initial dissolved O2 concentration values of 0.007, 0.01, 0.03, and 0.4 mM, degradation was achieved at 74.7%, 77.4%, 81.9% and 84.2%, respectively. Finally for values of initial Fe2+ ionsconcentration of 40, 9 and 2 mM, the phenol removal was achieved at 76.0%, 80.7% and 86.3%,respectively. After several simulations times, it was found [Cf]0 = 1000 mM were the optimum operatingconditions in which [O2]0 = 0.4 mM, [Fe2+]0 = 2 mM and I/A = 0.4 mA cm-2. With these values the phenol removal reached 99%, at dilution rate of 0.15 min-1. A viable model for phenol degradations proposed
Evaluation of Packed-Bed Reactor and Continuous Stirred Tank Reactor for the Production of Colchicine Derivatives  [PDF]
Kashyap Kumar Dubey,Dhirendra Kumar,Punit Kumar,Shafiul Haque,Arshad Jawed
ISRN Chemical Engineering , 2013, DOI: 10.1155/2013/865618
Abstract: Bioconversion of colchicine into its pharmacologically active derivative 3-demethylated colchicine (3-DMC) mediated by P450BM3 enzyme is an economic and promising strategy for the production of this inexpensive and potent anticancer drug. Continuous stirred tank reactor (CSTR) and packed-bed reactor (PBR) of 3?L and 2?L total volumes were compared for the production of 3-demethylated colchicine (3-DMC) a colchicine derivative using Bacillus megaterium MTCC*420 under aerobic conditions. Statistical optimization technique was utilized with the most significant variables, that is, dissolved oxygen (DO), colchicine concentration, and process time for optimization. The validation of the model was performed by experiments on the predicted values in an individual run, and the optimum parameters were DO (~50%), colchicine concentration (7.5?g/L), and process time (39?h) resulted in a maximum bioconversion of 3-DMC 3.36?g/L. The PBR reactor achieved much higher productivity (6.58?g/L/h) as reported by earlier researchers. This is the first report on the use of PBR for bioconversion of colchicine. 1. Introduction Bioreactor design is of crucial importance in the development of bioprocesses. Once a microorganism is selected and the culture and/or production conditions are optimized at laboratory scale, the next issue is proceeding to larger scale so that bulk quantities of the desired product can be produced optimally in a cost-effective manner. The selection of a proper reactor type is critical to such processes and plays a major role in large-scale production. The bioreactors widely used in today’s fermentation industry are mainly those developed in the past decades purely for chemical reactions [1, 2]. Among others, Stirred Tank Reactors (STRs) and Packed-Bed Reactors (PBRs) find the widest application. The application of these reactors for biological processes has been intensively studied with aerobic cultures [3–5]. Colchicine is a well-documented pseudo alkaloid obtained from Colchicum autumnale L. and Gloriosa superba, widely used in therapy for the treatment of gout pain persisting for a very long time [6, 7]. It is too toxic to be of value as an antitumor drug, in its native form. Derivatives of colchicine, that is, 3-demethylcolchicine, colchicoside, and thiocolchicoside with improved therapeutic properties for anti-inflammatory and anti-tumor drugs, have good commercial demand as these compounds are known to have clinical significance for the treatment of certain forms of leukemia and solid tumors [8, 9]. Colchicine and a number of its prepared
Characterization of a 5 Litre Continuous Stirred Tank Reactor  [PDF]
Philomena K. Igbokwe, Joseph T. Nwabanne, Samuel Wadzani Gadzama
World Journal of Engineering and Technology (WJET) , 2015, DOI: 10.4236/wjet.2015.32003
Abstract: Continuous Stirred Tank Reactors (CSTR) are used ubiquitously in chemical process industry for mixing, reactions and crystallizations. The purpose of this research is to study the effect of solute concentration (sodium chloride) on the stirrer speed in a CSTR. The experimental method used in this research is the stop watch and beaker method. The behavior pattern of the fluid in a CSTR can be experimentally verified as an alternative to the mathematical model. The tracer experiments were carried out. The effect of different parameters such as stirring speed, concentration at a steady time interval was analyzed. Experimental data obtained at 0.6 M and 160 rpm gave a curve that is in close agreement to that of theoretical or mathematical model. In other words, the results obtained at a concentration of 0.6 M and 160 rpm are in close agreement with that of early researchers. The paper is divided into five main sections: the first section immediately after the abstract is the introductory section that is basically a review of literature; the second section takes care of the materials and methods; the third section is the experimental procedure and this section takes the shut-down procedure and data processing into consideration; the fourth section is the discussion of experimental results and the last section is the conclusion of the paper.
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