Journal articles: 'Reactor physic'

1

Delpech, S., E. Merle-Lucotte, D. Heuer, M. Allibert, V. Ghetta, C. Le-Brun, X. Doligez, and G. Picard. "Reactor physic and reprocessing scheme for innovative molten salt reactor system." Journal of Fluorine Chemistry 130, no. 1 (January 2009): 11–17. http://dx.doi.org/10.1016/j.jfluchem.2008.07.009.

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Younan, Simon, and David R. Novog. "Development and Testing of TRACE/PARCS ECI Capability for Modelling CANDU Reactors with Reactor Regulating System Response." Science and Technology of Nuclear Installations 2022 (March 27, 2022): 1–31. http://dx.doi.org/10.1155/2022/7500629.

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The use of the USNRC codes TRACE and PARCS has been considered for the coupled safety analysis of CANDU reactors. A key element of CANDU simulations is the interactions between thermal-hydraulic and physic phenomena with the CANDU reactor regulating system (RRS). To date, no or limited development has taken place in TRACE-PARCS in this area. In this work, the system thermal-hydraulic code TRACE_Mac1.0 is natively coupled with the core physic code PARCS_Mac1.0, and RRS control is implemented via the exterior communications interface (ECI) in TRACE. ECI is used for coupling the external codes to TRACE, including additional physical models and control system models. In this work, a Python interface to the TRACE ECI library is developed, along with an RRS model written in Python. This coupling was tested using a CANDU-6 IAEA code coupling benchmark and a 900 MW CANDU model for various transients. For the CANDU-6 benchmark, the transients did not include RRS response, however, the TRACE_Mac1.0/PARCS_Mac1.0 coupling and ECI script functionality was compared to the previous benchmark simulations, which utilized external coupling. For the 900 MW CANDU simulations, all aspects of the ECI module and RRS were included. The results from the CANDU-6 benchmark when using the built-in coupling are comparable to those previously achieved using external coupling between the two codes with coupled simulations taking 2x to 3x less execution time. The 900 MW CANDU simulations successfully demonstrate the RRS functionality for the loss of flow events, and the coupled solutions demonstrate adequate performance for figure-of-eight flow instability modeling.

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Nguyen, Nhi Dien, Ba Vien Luong, Vinh Vinh Le, Van Dong Duong, Xuan Hai Nguyen, Ngoc Son Pham, and Dong Vu Cao. "Results of Operation and Utilization of the Dalat Nuclear Research Reactor." Nuclear Science and Technology 4, no. 1 (March 30, 2014): 1–9. http://dx.doi.org/10.53747/jnst.v4i1.208.

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The Dalat Nuclear Research Reactor (DNRR) with the nominal power of 500 kW was reconstructed and upgraded from the USA 250-kW TRIGA Mark-II reactor built in early 1960s. The renovated reactor was put into operation on 20th March 1984. It was designed for the purposes of radioisotope production (RI), neutron activation analysis (NAA), basic and applied researches, and nuclear education and training. During the last 30 years of operation, the DNRR was efficiently utilized for producing many kinds of radioisotopes and radiopharmaceuticals used in nuclear medicine centers and other users in industry, agriculture, hydrology and scientific research; developing a combination of nuclear analysis techniques (INAA, RNAA, PGNAA) and physic-chemical methods for quantitative analysis of about 70 elements and constituents in various samples; carrying out experiments on the reactor horizontal beam tubes for nuclear data measurement, neutron radiography and nuclear structure study; and establishing nuclear training and education programs for human resource development. This paper presents the results of operation and utilization of the DNRR. In addition, some main reactor renovation projects carried out during the last 10 years are also mentioned in the paper.

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Pascal, V., Y. Gorsse, N. Alpy, K. Ammar, M. Anderhuber, AM Baudron, G. Campioni, et al. "MULTIPHYSICS MODELISATION OF AN UNPROTECTED LOSS OF FLOW TRANSIENT IN A SODIUM COOLED FAST REACTORS USING A NEUTRONIC-THERMAL-HYDRAULIC COUPLING SCHEME." EPJ Web of Conferences 247 (2021): 07001. http://dx.doi.org/10.1051/epjconf/202124707001.

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Sodium cooled fast neutron reactors (SFR) are one of the selected reactor concepts in the framework of the Generation IV International Forum. In this concept, unprotected loss of cooling flow transients (ULOF), for which the non-triggering of backup systems is postulated, are regarded as potential initiators of core melting accidents. During an ULOF transient, spatial distributions of fuel, structure and sodium temperatures are affected by the core cooling flow decrease, which will modify the spatial and energy distribution of neutron in the core due to the spatial competition of neutron feedback effects. As no backup systems are triggered, sodium may reach its boiling temperature at some point, leading to local sodium density variations and making the transient fluctuate in a two-phase flow physics where thermal-hydraulics and neutronics may interact with each other. The transient phenomenology involves several physic disciplines at different time and spatial scales, such as core neutronics, coolant thermal-hydraulics and fuel thermo-mechanics. This paper presents the results of thermal-hydraulic/neutronic coupled simulations of an ULOF transient on the SFR project ASTRID. These coupled calculations are based on the supervisor platform SALOME to link the neutron code APOLLO3® to the system thermal-hydraulic code CATHARE3. The physical approach used by the coupling to describe the neutron kinetic is a quasi-static adiabatic one, updating the normalized spatial power distribution periodically by performing static neutron calculations, while a point kinetic model associated to a neutron feedback model calculates the power amplitude variations.

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Nowak, Agata, Robert Mazur, Ewa Panek, and Joanna Chmist. "Model Studies on the Effectiveness of MBBR Reactors for the Restoration of Small Water Reservoirs." E3S Web of Conferences 30 (2018): 02004. http://dx.doi.org/10.1051/e3sconf/20183002004.

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The authors present the Moving Bed Biofilm Reactor (MBBR) model with a quasi-continuous flow for small water reservoir restoration, characterized by high concentrations of organic pollutants. To determine the efficiency of wastewater treatment the laboratory analysis of physic-chemical parameters were conducted for the model on a semi-technical scale of 1:3. Wastewater treatment process was carried out in 24 h for 1 m3 for raw sewage. The startup period was 2 weeks for all biofilters (biological beds). Approximately 50% reduction in COD and BOD5 was obtained on average for the studied bioreactors. Significant improvements were achieved in theclarity of the treated wastewater, with the reduction of suspension by 60%. The oxygen profile has improved significantly in 7 to 9 hours of the process, and a diametric reduction in the oxidative reduction potential was recorded. A preliminary model of biological treatment effectiveness was determined based on the conducted studies. In final stages, the operation mode was set in real conditions of polluted water reservoirs.

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Maria F, Lencina, Robinson Ada J, Rearte Samanta M, and Albarracín Patricia M. "Production of unicelular protein and reduction of contaminating amount of vinasse." Journal of Applied Biotechnology & Bioengineering 9, no. 6 (December 26, 2022): 229–31. http://dx.doi.org/10.15406/jabb.2022.09.00315.

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The vinasse from ethanol distillery, which is a highly contaminating industrial waste, is produced in large quantities. Through biotechnology, it can be used for the production of protein while reducing contamination. The Candida utilis strain was isolated and adapted under different concentrations of aqueous formulas of vinasse, from 10 to 50%. The experimental trials were carried out in a lab using a “batch” reactor with vinasse. The growth of the microorganism was monitored using a carbon dioxide sensor (CO2). The parameters measured were: total nitrogen, COD (chemical demand of oxygen), pH and conductivity, at the beginning and end of each trial. Every two hours, the DO (optics density in a liquid environment) was measured with the objective of knowing its cellular concentration. For each physic- chemical variable analyzed, an ANOVA was realized to evaluate the factors of repetition, treatment and reactor, and it was chosen a significance level of 1%. The parameters measured reported: in total nitrogen there was an enrichment of 136% in the environment composed of 50% of vinasse in aqueous formulas; the average removal of the chemical demand of oxygen was 43%; the variation of pH, which was compared at the end of the trials, was 4% less than at the beginning; and the conductivity lessened to 9%. The monitoring of yeast growth by measuring the carbon dioxide concentrations throughout the time and the environment’s OD, allowed for the creation of a growth curve of the microorganism, with a fermentation period of 21 hours. It was proved that the Candida utilis strain can develop in a batch reactor with vinasse, in aqueous solutions of 50%, and producing a proteic enrichment of it as well as the removal of COD. The proposed process reduces the contamination of the main industrial effluent of Tucumán

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Ahmad Latiffi, Nur Atikah, Radin Maya Saphira Radin Mohamed, Najeeha Mohd Apandi, and Amir Hashim Mohd Kassim. "Application of Phycoremediation Using Microalgae Scenedesmus sp. as Wastewater Treatment in Removal of Heavy Metals from Food Stall Wastewater." Applied Mechanics and Materials 773-774 (July 2015): 1168–72. http://dx.doi.org/10.4028/www.scientific.net/amm.773-774.1168.

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This paper represents the results of using phycoremediation technology in treating the wastewater produced from food stall activity by using microalgae of Scenedesmus sp. in removal of heavy metals. Phycoremediation has advantages over physic-chemical approaches as it is can completely degrade organic pollutants without destroy the surrounding flora and fauna. Aim of this study is to determine the effectiveness of microalgae Scenedesmussp to assimilate the pollutant load based on the optimum time and concentration. Characteristics of food stall wastewater need to be identified and analyse before phycoremediation process taken place. The wastewater sampling was collected at food stall during peak time i.e. at 8 a.m. and 4 p.m. Microalgae Scenedesmus sp. to be injected to the batch reactor based on five (5) different concentration cells. The results shows that the optimum removal of heavy metals are dominant by concentration no. 1 (C1) compare to other concentration in the treatment i.e. removal of Ferum by 88.22% and 69.63%, Copper by 60% and 53.85% at both sampling time while removal of zinc is dominant by concentration no.4 (C4) by 75.61% and 76.63% respectively.

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Foffi, Rachele, Elisa Savuto, Matteo Stante, Roberta Mancini, and Katia Gallucci. "Study of Energy Valorization of Disposable Masks via Thermochemical Processes: Devolatilization Tests and Simulation Approach." Energies 15, no. 6 (March 13, 2022): 2103. http://dx.doi.org/10.3390/en15062103.

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The COVID-19 pandemic exacerbated the use of medical protective equipment, including face masks, to protect the individual from the virus. This work studies the feasibility of using these materials as fuel for thermochemical processes for the production of syngas. A preliminary physic-chemical characterization was made by means of moisture and ash determination, thermogravimetric analysis, X-ray fluorescence. Afterward, pyrolysis and gasification tests were executed in a laboratory-scale fluidized bed reactor with chirurgical and FFP2 masks investigating four temperature levels and three different operating conditions (fluidizing agents and dry/wet sample). A qualitative and quantitative analysis of condensable aromatic hydrocarbons in the produced gas, collected during the test campaign, was performed employing a gas chromatograph-mass spectrometer. The experimental data from the tests were used to propose a hybrid approach to simulate the gasification process, based on experimental laws for the devolatilization step and a thermodynamic equilibrium approach for char gasification. The resulting data were compared with a thermodynamic equilibrium model, showing that the new approach captures non-equilibrium effects always present in real gasifiers operation.

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Смолин and V. Smolin. "Mathematical Simulation of Biotechnical Scanner to Determine Hydration Degrees a Biological Tissue in Norme and at Different Pathologies." Journal of New Medical Technologies 22, no. 1 (February 11, 2015): 11–16. http://dx.doi.org/10.12737/9068.

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The organs and tissues of the living body depending on the structure and functional states can contain from 50 to 90% of water. Water in a living organism can be in two forms: free water and structured water. Structured water forms strong links with organic molecules. Free water is movable, its quantity can vary considerably depending on the functional state of the body and determines a hydration degree of a tissues. In clinical practice, the existing technical possibilities of determining hydration degree of biological objects are li-mited and hardly used. Any conclusions about the cause of death due to swelling are not sufficiently and quantified justified. This paper is devoted to the development of a mathematical model of biotechnical scanner to determine the degree of hydration of biological tissues, based on the physic-chemical effect caused by additive volume of the system in the interaction of the sample of biological tissue with ethanol. The mathematical model demonstrated that the violations of additivity volume are observed even with the addition of small water volume to large alcohol volume. A probabilistic model was developed and shown that the effects of the exothermic reaction, mixing water and ethanol, have a strong effect on the dates of the process. But this fixing process of a biological object is extended during times, the studied system by the end of fixation will go down in the stationary regime, which will determine the degree of hydration. Registration changes of the system volume during the interaction of a biological object with ethanol allows to studying the dynamics of physical and chemical processes in the reactor of biotechnical scanner.

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10

Katsioulas, I., I. Savvidis, and C. Eleftheriadis. "Nuclear Reactor Neutrino Detection with the Spherical Proportional Counter." HNPS Proceedings 21 (March 8, 2019): 92. http://dx.doi.org/10.12681/hnps.2010.

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Nuclear Power Reactors are the most powerful neutrino sources as they emit large numbers of antineu- trinos, at energies up to 10 MeV. The reactor neutrino detection is very important for fundamental physics goals, as well as for applications, among them being the possibility to determine the isotopic composition of the reactor’s core. This could lead to application of neutrino spectroscopy for reactor monitoring, either for improving the reliability of operation of power reactors or as a method to accomplish certain safeguard and non-proliferation objectives. We present here the conditions on detecting neutrinos coming from nuclear reactors with the Spherical Proportional Counter (SPC), by exploiting the coherent neutrino-nucleus elastic scattering.

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11

Szatmáry, Zoltán. "Reactor physics experimental data for VVER type reactors." Acta Physica Hungarica A) Heavy Ion Physics 7, no. 2 (December 1998): 219–34. http://dx.doi.org/10.1007/bf03158347.

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12

Fíla, Vlastimil, and Bohumil Bernauer. "A Mathematical Model of a Gauze Reactor for the Ammonia Oxidation." Collection of Czechoslovak Chemical Communications 59, no. 4 (1994): 855–74. http://dx.doi.org/10.1135/cccc19940855.

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The behaviour of an industrial reactor for the oxidation of ammonia with Pt-Rh gauzes was simulated by means of a mathematical model accounting for the axial dispersion of the components, radiative heat transmission in the reactor, and the effect of temperature on the physico-chemical properties of the reacting mixture. The effect of the preheating temperature, the input mixture composition, pressure and reactor load on the temperature distribution in the catalyst bed and on the NO yield was examined. The calculated NO yields agree well with the values actually attained in industrial reactors. The effect of the reaction mixture composition and total pressure on the yield is also consistent with observed dependences.

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Kalyuzhnyi, Sergey, and Vyacheslav Fedorovich. "Integrated mathematical model of UASB reactor for competition between sulphate reduction and methanogenesis." Water Science and Technology 36, no. 6-7 (September 1, 1997): 201–8. http://dx.doi.org/10.2166/wst.1997.0592.

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The existing mathematical models of anaerobic treatment processes were mainly developed for ideally mixed reactors with no concentration gradients on substrates, intermediates, products and bacteria inside the reactor. But for conventional UASB reactors with low upward velocity, the distribution of these components along the reactor height is very far from uniform. This paper presents an integrated mathematical model of the functioning of UASB reactor taking into account this non-uniformity as well as multiple-reaction stoichiometry and kinetics. In general, our integrated model includes the following blocks: a) kinetic block, including the growth and metabolism of acidogenic, acetogenic, methanogenic and sulphate-reducing bacteria; b) physico-chemical block, for the calculation of pH in each compartment of the liquid phase; c) hydrodynamic block, describing liquid flow as well as the transport and distribution of the components along the reactor height; d) transfer block, describing a mass transfer of gaseous components from the liquid to gas phase. This model was calibrated to some experimental studies of the functioning of UASB reactors made by in 1994. Hypothetical computer simulations are presented to illustrate the influence of different factors (recycle number, hydraulic retention time, quality of seed sludge, SO42−:COD ratio etc.) on the operation performance of UASB reactor.

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Zeyer, K. P., G. Dechert, W. Hohmann, R. Blittersdorf, and F. W. Schneider. "Coupled Bistable Chemical Systems - Experimental Realization of Boolean Functions Using a Simple Feedforward Net." Zeitschrift für Naturforschung A 49, no. 10 (October 1, 1994): 953–63. http://dx.doi.org/10.1515/zna-1994-1010.

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AbstractWe use the BZ-reaction and the MBO-reaction to implement the Boolean functions AND, OR, NAND , and NOR by the coupling of three chemical reactors. The experimental setup is analogous to a simple neural feedforward network with two reactors serving as the input layer and one reactor as the output layer. Coupling between the input and output reactors is carried out through the flow rate (BZ- and MBO-reaction) and through the electrical current by the use of Pt working electrodes (BZ-reaction). The XOR- and XN OR functions may be realized with 5 reactors using combinations of the AND, NOR, NOR - and the AND, NOR, Or-chemical gates, respectively.

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Ripani, M. "Energy from nuclear fission." EPJ Web of Conferences 268 (2022): 00010. http://dx.doi.org/10.1051/epjconf/202226800010.

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The physics of nuclear fission will be briefly illustrated, from the basic mechanism behind this phenomenon to the relevant physical quantities like nuclear cross sections, neutron flux and reaction products, together with the accompanying phenomenon of neutron capture and its role in determining how the fuel transforms in a nuclear reactor. The basic concepts underlying the operation of diﬀerent types of nuclear reactors will be illustrated, along with the concept of fuel cycle. The aspects of radioactive waste, fuel resources and safety will also be briefly illustrated.

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Ochoa-Ricoux, J. P. "Neutrino Physics with Nuclear Reactors: An Overview." International Journal of Modern Physics: Conference Series 46 (January 2018): 1860001. http://dx.doi.org/10.1142/s2010194518600017.

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Nuclear reactors provide an excellent environment for studying neutrinos and continue to play a critical role in unveiling the secrets of these elusive particles. A rich experimental program with reactor antineutrinos is currently ongoing, and leads the way in precision measurements of several oscillation parameters and in searching for new physics, such as the existence of light sterile neutrinos. Ongoing experiments have also been able to measure the flux and spectral shape of reactor antineutrinos with unprecedented statistics and as a function of core fuel evolution, uncovering anomalies that will lead to new physics and/or to an improved understanding of antineutrino emission from nuclear reactors. The future looks bright, with an aggressive program of next generation reactor neutrino experiments that will go after some of the biggest open questions in the field. This includes the JUNO experiment, the largest liquid scintillator detector ever constructed which will push the limits of this detection technology.

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Davies, Sebastian, Dzianis Litskevich, Ulrich Rohde, Anna Detkina, Bruno Merk, Paul Bryce, Andrew Levers, and Venkata Ravindra. "DYN3D and CTF Coupling within a Multiscale and Multiphysics Software Development (Part I)." Energies 14, no. 16 (August 17, 2021): 5060. http://dx.doi.org/10.3390/en14165060.

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Understanding and optimizing the relation between nuclear reactor components or physical phenomena allows us to improve the economics and safety of nuclear reactors, deliver new nuclear reactor designs, and educate nuclear staff. Such relation in the case of the reactor core is described by coupled reactor physics as heat transfer depends on energy production while energy production depends on heat transfer with almost none of the available codes providing full coupled reactor physics at the fuel pin level. A Multiscale and Multiphysics nuclear software development between NURESIM and CASL for LWRs has been proposed for the UK. Improved coupled reactor physics at the fuel pin level can be simulated through coupling nodal codes such as DYN3D as well as subchannel codes such as CTF. In this journal article, the first part of the DYN3D and CTF coupling within the Multiscale and Multiphysics software development is presented to evaluate all inner iterations within one outer iteration to provide partially verified improved coupled reactor physics at the fuel pin level. Such verification has proven that the DYN3D and CTF coupling provides improved feedback distributions over the DYN3D coupling as crossflow and turbulent mixing are present in the former.

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Motevalli, Seyed Mohammad, and Fereshteh Fadaei. "A Comparison Between the Burn Condition of Deuterium–Tritium and Deuterium–Helium-3 Reaction and Stability Limits." Zeitschrift für Naturforschung A 70, no. 2 (February 1, 2015): 79–84. http://dx.doi.org/10.1515/zna-2014-0134.

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AbstractThe nuclear reaction of deuterium–tritium (D–T) fusion by the usual magnetic or inertial confinement suffers from a number of difficulties and problems caused by tritium handling, neutron damage to materials and neutron-induced radioactivity, etc. The study of the nuclear synthesis reaction of deuterium–helium-3 (D–3He) at low collision energies (below 1 keV) is of interest for its applications in nuclear physics and astrophysics. Spherical tokamak (ST) reactors have a low aspect ratio and can confine plasma with β≈1. These capabilities of ST reactors are due to the use of the alternative D–3He reaction. In this work, the burn condition of D–3He reaction was calculated by using zero-dimensional particles and power equations, and, with the use of the parameters of the ST reactor, the stability limit of D–3He reaction was calculated and then the results were compared with those of D–T reaction. The obtained results show that the burn conditions of D–3He reaction required a higher temperature and had a much more limited temperature range in comparison to those of D–T reaction.

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Kliem, S. "Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2014." Kerntechnik 80, no. 4 (August 27, 2015): 304. http://dx.doi.org/10.3139/124.015041.

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Kliem, S. "Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2015." Kerntechnik 81, no. 4 (August 26, 2016): 355. http://dx.doi.org/10.3139/124.016041.

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Kliem, S. "Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2016." Kerntechnik 82, no. 4 (September 2017): 364. http://dx.doi.org/10.3139/124.017041.

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Kliem, S. "Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2017." Kerntechnik 83, no. 4 (August 27, 2018): 266–67. http://dx.doi.org/10.3139/124.018041.

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Kliem, S. "Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2018." Kerntechnik 84, no. 4 (September 16, 2019): 212–13. http://dx.doi.org/10.3139/124.019041.

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Kliem, S. "Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2019." Kerntechnik 85, no. 4 (September 14, 2020): 198. http://dx.doi.org/10.3139/124.020041.

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Davies, Sebastian, Dzianis Litskevich, Bruno Merk, Andrew Levers, Paul Bryce, and Anna Detkina. "DYN3D and CTF Coupling within a Multiscale and Multiphysics Software Development (Part II)." Energies 15, no. 13 (July 1, 2022): 4843. http://dx.doi.org/10.3390/en15134843.

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Traditionally, the complex coupled physical phenomena in nuclear reactors has resulted in them being treated separately or, at most, simplistically coupled in between within nuclear codes. Currently, coupling software environments are allowing different types of coupling, modularizing the nuclear codes or multi-physics. Several multiscale and multi-physics software developments for LWR are incorporating these to deliver improved or full coupled reactor physics at the fuel pin level. An alternative multiscale and multi-physics nuclear software development between NURESIM and CASL is being created for the UK. The coupling between DYN3D nodal code and CTF subchannel code can be used to deliver improved coupled reactor physics at the fuel pin level. In the current journal article, the second part of the DYN3D and CTF coupling was carried out to analyse a parallel two-way coupling between these codes and, hence, the outer iterations necessary for convergence to deliver verified improved coupled reactor physics at the fuel pin level. This final verification shows that the DYN3D and CTF coupling delivers improved effective multiplication factors, fission, and feedback distributions due to the presence of crossflow and turbulent mixing.

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Kong, Rui, Lingen Chen, Shaojun Xia, Penglei Li, and Yanlin Ge. "Minimization of Entropy Generation Rate in Hydrogen Iodide Decomposition Reactor Heated by High-Temperature Helium." Entropy 23, no. 1 (January 8, 2021): 82. http://dx.doi.org/10.3390/e23010082.

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The thermochemical sulfur-iodine cycle is a potential method for hydrogen production, and the hydrogen iodide (HI) decomposition is the key step to determine the efficiency of hydrogen production in the cycle. To further reduce the irreversibility of various transmission processes in the HI decomposition reaction, a one-dimensional plug flow model of HI decomposition tubular reactor is established, and performance optimization with entropy generate rate minimization (EGRM) in the decomposition reaction system as an optimization goal based on finite-time thermodynamics is carried out. The reference reactor is heated counter-currently by high-temperature helium gas, the optimal reactor and the modified reactor are designed based on the reference reactor design parameters. With the EGRM as the optimization goal, the optimal control method is used to solve the optimal configuration of the reactor under the condition that both the reactant inlet state and hydrogen production rate are fixed, and the optimal value of total EGR in the reactor is reduced by 13.3% compared with the reference value. The reference reactor is improved on the basis of the total EGR in the optimal reactor, two modified reactors with increased length are designed under the condition of changing the helium inlet state. The total EGR of the two modified reactors are the same as that of the optimal reactor, which are realized by decreasing the helium inlet temperature and helium inlet flow rate, respectively. The results show that the EGR of heat transfer accounts for a large proportion, and the decrease of total EGR is mainly caused by reducing heat transfer irreversibility. The local total EGR of the optimal reactor distribution is more uniform, which approximately confirms the principle of equipartition of entropy production. The EGR distributions of the modified reactors are similar to that of the reference reactor, but the reactor length increases significantly, bringing a relatively large pressure drop. The research results have certain guiding significance to the optimum design of HI decomposition reactors.

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Kong, Rui, Lingen Chen, Shaojun Xia, Penglei Li, and Yanlin Ge. "Minimization of Entropy Generation Rate in Hydrogen Iodide Decomposition Reactor Heated by High-Temperature Helium." Entropy 23, no. 1 (January 8, 2021): 82. http://dx.doi.org/10.3390/e23010082.

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The thermochemical sulfur-iodine cycle is a potential method for hydrogen production, and the hydrogen iodide (HI) decomposition is the key step to determine the efficiency of hydrogen production in the cycle. To further reduce the irreversibility of various transmission processes in the HI decomposition reaction, a one-dimensional plug flow model of HI decomposition tubular reactor is established, and performance optimization with entropy generate rate minimization (EGRM) in the decomposition reaction system as an optimization goal based on finite-time thermodynamics is carried out. The reference reactor is heated counter-currently by high-temperature helium gas, the optimal reactor and the modified reactor are designed based on the reference reactor design parameters. With the EGRM as the optimization goal, the optimal control method is used to solve the optimal configuration of the reactor under the condition that both the reactant inlet state and hydrogen production rate are fixed, and the optimal value of total EGR in the reactor is reduced by 13.3% compared with the reference value. The reference reactor is improved on the basis of the total EGR in the optimal reactor, two modified reactors with increased length are designed under the condition of changing the helium inlet state. The total EGR of the two modified reactors are the same as that of the optimal reactor, which are realized by decreasing the helium inlet temperature and helium inlet flow rate, respectively. The results show that the EGR of heat transfer accounts for a large proportion, and the decrease of total EGR is mainly caused by reducing heat transfer irreversibility. The local total EGR of the optimal reactor distribution is more uniform, which approximately confirms the principle of equipartition of entropy production. The EGR distributions of the modified reactors are similar to that of the reference reactor, but the reactor length increases significantly, bringing a relatively large pressure drop. The research results have certain guiding significance to the optimum design of HI decomposition reactors.

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Bernnat, W., and W. Feltes. "Models for reactor physics calculations for HTR pebble bed modular reactors." Nuclear Engineering and Design 222, no. 2-3 (June 2003): 331–47. http://dx.doi.org/10.1016/s0029-5493(03)00036-0.

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Jagannathan, V., Usha Pal, R. Karthikeyan, Devesh Raj, Argala Srivastava, and Suhail Ahmad Khan. "Reactor physics ideas to design novel reactors with faster fissile growth." Energy Conversion and Management 49, no. 8 (August 2008): 2032–46. http://dx.doi.org/10.1016/j.enconman.2008.02.019.

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TAKEDA, Toshikazu. "Microscopic Reactor Physics." Journal of the Atomic Energy Society of Japan / Atomic Energy Society of Japan 41, no. 11 (1999): 1157–61. http://dx.doi.org/10.3327/jaesj.41.1157.

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Williams, M. M. R. "Nuclear Reactor Physics." Annals of Nuclear Energy 28, no. 17 (November 2001): 1783–87. http://dx.doi.org/10.1016/s0306-4549(01)00071-8.

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Liu, Ren Wei, Zhong Dong Yin, Song Wei Cao, and Heng Rui Ma. "Research on Neutral Grounding Reactance Allocation with MCR." Advanced Materials Research 816-817 (September 2013): 997–1001. http://dx.doi.org/10.4028/www.scientific.net/amr.816-817.997.

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For the arc current generated during the reclosing of the high-voltage transmission system, small reactance configuration compensation and control strategy. By the magnetically controlled reactor is researched. First analyzing the principle that high-pressure single-circuit and double-circuit on the same pole line suppresses arc current, then establishing the magnetron controlled reactor equivalent model in PSCAD, on this basis, establishing simulation using magnetron reactors to suppress secondary arc current circuit under the conditions of high voltage transmission lines , designing and implementing of a magnetic valve controllable reactor inhibition of arc current physics experiments under of a low-voltage experimental conditions analoging high-voltage actual line condition. At last, the comparison of PSCAD simulation waveform and physics experiments of Power Quality the analyzer topas2000 and oscilloscope output verify the magnetic valve controllable reactor to suppress the arc current theory feasibility and effectiveness.

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Losa, Evžen, Michal Košťál, Tomáš Czakoj, Jan Šimon, Nicola Burianová, Vlastimil Juříček, and Vojtěch Rypar. "NEUTRON FIELD MOCK-UP DEVELOPMENT FOR THE FLUORIDE SALT REACTORS NEUTRONIC RESEARCH." EPJ Web of Conferences 247 (2021): 08013. http://dx.doi.org/10.1051/epjconf/202124708013.

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Experimental work at the LR-0 reactor was carried out to determine the possibility of the mock-up neutron field creation for the fluoride salt-based reactors. Previous calculations and experiments have shown that the fast part of the molten salt reactor (MSR) spectrum is shaped by fluorine and even the Teflon material is suitable for neutronics in that energy range. Properly selected spectrum indices can describe the neutron field of the MSR in fast thermal and intermediate parts of the spectrum. Current research has focused on a deeper study of the possibility of using the filtered thermal and intermediate neutron spectrum of the experimental light water reactor for the physics of fluoride salt-based reactor. LiF-BeF2 (FLIBE) capsule and teflon cylinders are used as a spectrum filters in the LR-0 reactor. Measured results show acceptable C/E-1 agreement in the reaction rates and satisfactory agreement for usage of the FLIBE filtered neutron spectrum determined by the 181Ta(n, γ) monitor as a mock-up in thermal to intermediate energy in the fluoride high-temperature reactor (FHR). Concerning MSR, intermediate spectrum can be reproduced to some extent but not as good as in the case of FHR.

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Ripani, M. "Energy from nuclear fission." EPJ Web of Conferences 246 (2020): 00010. http://dx.doi.org/10.1051/epjconf/202024600010.

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The physics of nuclear fission will be briefly illustrated, from the basic mechanism behind this phenomenon to the relevant physical quantities like nuclear cross sections, neutron flux and reaction products, together with the accompanying phenomenon of neutron capture and its role in determining how the fuel transforms in a nuclear reactor. The basic concepts underlying the operation of different types of nuclear reactors will be illustrated, along with the concept of fuel cycle. After touching on the aspect of safety, the current situation of nuclear power in the world, with its costs, its role in reducing carbon emissions, the available resources and finally the issues of waste management and accidents will be briefly illustrated.

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Franklin, Simon. "Reactor reaction." Physics World 11, no. 5 (May 1998): 22. http://dx.doi.org/10.1088/2058-7058/11/5/20.

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Schwarz, Alexander, Marek Mösche, Ahrend Wittenberg, Hans-Joachim Jördening, Klaus Buchholz, and Matthias Reuss. "Mathematical modelling and simulation of an industrial scale fluidized bed reactor for anaerobic wastewater treatment – scale-up effect on pH-gradients." Water Science and Technology 36, no. 6-7 (September 1, 1997): 219–27. http://dx.doi.org/10.2166/wst.1997.0594.

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A mathematical model of anaerobic wastewater treatment in an industrial scale fluidized bed reactor (FBR) is presented together with simulation results for reactors in lab-scale (1 l) and industrial scale (500 m3). The model was developed to study the effect of scale up on the anaerobic wastewater treatment in FBRs by examining the interactions between biological degradation and the physico-chemical environment upon the outcome of this process. Material balance equations for substrates and products in gas and liquid phase are basis of the model. Hereby, the following effects were taken into account: biological degradation steps, convection and dispersion, chemical equilibria and calcium carbonate precipitation under consideration of ion activities. Model extensions are discussed, for example the calcium carbonate precipitation and the pH-dependency of degradation reactions. Simulation results show the strong impact of reactor performance on axial pH-gradients and thus on process stability in dependence of reactor scale. In this context the crucial role of the precipitation reaction together with the substrate degradation und carbon dioxide production reactions on local pH-values in the system is illustrated.

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Dranga, Ruxandra, Laura Blomeley, and Rebecca Carrington. "AN MCNP PARAMETRIC STUDY OF GEORGE C. LAURENCE'S SUBCRITICAL PILE EXPERIMENT." AECL Nuclear Review 3, no. 2 (December 1, 2014): 91–99. http://dx.doi.org/10.12943/anr.2014.00037.

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In the early 1940s at the National Research Council (NRC) Laboratories in Ottawa, Canada, Dr. George Laurence conducted several experiments to determine if a sustained nuclear fission chain reaction in a carbon–uranium arrangement (or “pile”) was possible. Although Dr. Laurence did not achieve criticality, these pioneering experiments marked a significant historical event in nuclear science, and they provided a valuable reference for subsequent experiments that led to the design of Canada’s first heavy-water reactors at the Chalk River Nuclear Laboratories. This paper summarizes the results of a recent collaborative project between Atomic Energy of Canada Limited and the Deep River Science Academy undertaken to numerically explore the experiments carried out at the NRC Laboratories by Dr. Laurence, while teaching high school students about nuclear science and technology. In this study, a modern Monte Carlo reactor physics code, MCNP6, was utilized to identify and study the key parameters impacting the subcritical pile’s neutron multiplication factor (e.g., moderation, geometry, material impurities) and quantify their effect on the extent of subcriticality. The findings presented constitute the first endeavour to model, using a current computational reactor physics tool, the seminal experiment that provided the foundation of Canada’s nuclear science and technology program.

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Avramova, Maria, Agustin Abarca, Jason Hou, and Kostadin Ivanov. "Innovations in Multi-Physics Methods Development, Validation, and Uncertainty Quantification." Journal of Nuclear Engineering 2, no. 1 (March 7, 2021): 44–56. http://dx.doi.org/10.3390/jne2010005.

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This paper provides a review of current and upcoming innovations in development, validation, and uncertainty quantification of nuclear reactor multi-physics simulation methods. Multi-physics modelling and simulations (M&S) provide more accurate and realistic predictions of the nuclear reactors behavior including local safety parameters. Multi-physics M&S tools can be subdivided in two groups: traditional multi-physics M&S on assembly/channel spatial scale (currently used in industry and regulation), and novel high-fidelity multi-physics M&S on pin (sub-pin)/sub-channel spatial scale. The current trends in reactor design and safety analysis are towards further development, verification, and validation of multi-physics multi-scale M&S combined with uncertainty quantification and propagation. Approaches currently applied for validation of the traditional multi-physics M&S are summarized and illustrated using established Nuclear Energy Agency/Organization for Economic Cooperation and Development (NEA/OECD) multi-physics benchmarks. Novel high-fidelity multi-physics M&S allow for insights crucial to resolve industry challenge and high impact problems previously impossible with the traditional tools. Challenges in validation of novel multi-physics M&S are discussed along with the needs for developing validation benchmarks based on experimental data. Due to their complexity, the novel multi-physics codes are still computationally expensive for routine applications. This fact motivates the use of high-fidelity novel models and codes to inform the low-fidelity traditional models and codes, leading to improved traditional multi-physics M&S. The uncertainty quantification and propagation across different scales (multi-scale) and multi-physics phenomena are demonstrated using the OECD/NEA Light Water Reactor Uncertainty Analysis in Modelling benchmark framework. Finally, the increasing role of data science and analytics techniques in development and validation of multi-physics M&S is summarized.

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Saadatian-derakhshandeh, Farahnaz, Omid Safarzadeh, and Amir Saiid Shirani. "Estimation of Control Rod Worth in a VVER-1000 Reactor using DRAGON4 and DONJON4." Nukleonika 59, no. 2 (July 8, 2014): 67–72. http://dx.doi.org/10.2478/nuka-2014-0006.

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Abstract One of the main issues in safety and control systems design of power and research reactors is to prevent accidents or reduce the imposed hazard. Control rod worth plays an important role in safety and control of reactors. In this paper, we developed a justifiable approach called D4D4 to estimate the control rod worth of a VVER-1000 reactor that enables to perform the best estimate analysis and reduce the conservatism that utilize DRAGON4 and DONJON4. The results are compared with WIMS-D4/CITATION to show the effectiveness and superiority of the developed package in predicting reactivity worth of the rod and also other reactor physics parameters of the VVER-1000 reactor. The results of this study are in good agreement with the plant's FSAR.

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Lindley, Ben, Brendan Tollit, Peter Smith, Alan Charles, Robert Mason, Tim Ware, Ray Perry, Jean Lavarenne, Una Davies, and Robert Gregg. "FAST REACTOR MULTIPHYSICS AND UNCERTAINTY PROPAGATION WITHIN WIMS." EPJ Web of Conferences 247 (2021): 06002. http://dx.doi.org/10.1051/epjconf/202124706002.

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For liquid metal-cooled fast reactors (LMFRs), improved predictive modelling is desirable to facilitate reactor licensing and operation and move towards a best estimate plus uncertainty (BEPU) approach. A key source of uncertainty in fast reactor calculations arises from the underlying nuclear data. Addressing the propagation of such uncertainties through multiphysics calculations schemes is therefore of importance, and is being addressed through international projects such as the Sodium-cooled Fast Reactor Uncertainty Analysis in Modelling (SFR-UAM) benchmark. In this paper, a methodology for propagation of nuclear data uncertainties within WIMS is presented. Uncertainties on key reactor physics parameters are calculated for selected SFR-UAM benchmark exercises, with good agreement with previous results. A methodology for coupled neutronic-thermal-hydraulic calculations within WIMS is developed, where thermal feedback is introduced to the neutronic solution through coupling with the ARTHUR subchannel code within WIMS and applied to steady-state analysis of the Horizon 2020 ESFR-SMART project reference core. Finally, integration of reactor physics and fuel performance calculations is demonstrated through linking of the WIMS reactor physics code to the TRAFIC fast reactor fuel performance code, through a Fortran-C-Python (FCP) interface. Given the 3D multiphysics calculation methodology, thermal-hydraulic and fuel performance uncertainties can ultimately be sampled alongside the nuclear data uncertainties. Together, these developments are therefore an important step towards enabling propagation of uncertainties through high fidelity, multiphysics SFR calculations and hence facilitate BEPU methodologies.

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41

Mo¨ller, S., and R. Palumbo. "The Development of a Solar Chemical Reactor for the Direct Thermal Dissociation of Zinc Oxide." Journal of Solar Energy Engineering 123, no. 2 (November 1, 2000): 83–90. http://dx.doi.org/10.1115/1.1349717.

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A solar chemical reactor was designed, constructed and tested for the direct thermal decomposition of zinc oxide at temperatures as high as 2250 K using concentrated sunlight. Along with the reactor, a 1-dimensional numerical model was developed to predict the reactor’s thermal performance under various solar flux levels and to identify the physio-chemical properties of ZnO that are critical for designing the reactor. An experimental study was also conducted to ascertain how best to employ a curtain of inert gas to keep the reactor’s window clean of Zn and ZnO. The reactor proved to be a reliable research tool for effecting the decomposition reaction and it possesses many features characteristic of a reactor scale-able to an industrial level: it is resilient to thermal shock; it has a low effective thermal inertia, and it can operate in a continuous mode when ZnO as a powder is fed to the reactor. Furthermore, experimental work led to insight on how best to keep the window clean in the course of an experiment. Also, comparisons between output from the numerical model and experimental results show that the solar flux and the ZnO’s thermal conductivity and emissivity are the most critical variables affecting the exergy efficiency of the reactor and the mass flux of product gases. The comparison further reveals the need to investigate whether or not the magnitude of the published pre-exponential term in the decomposition rate equation used in the numerical model should be reduced for improving agreement between the model and the experimental results.

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42

Hill, I. "IDENTIFICATION OF REACTOR PHYSICS BENCHMARKS FOR NUCLEAR DATA TESTING: TOOLS AND EXAMPLES." EPJ Web of Conferences 247 (2021): 10028. http://dx.doi.org/10.1051/epjconf/202124710028.

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Measurements of reactor physics quantities aimed at identifying the reactivity worth of materials, spectral ratios of cross-sections, and reactivity coefficients have ensured reactor physics codes can accurately predict nuclear reactor systems. These measurements were critical in the absence of sufficiently accurate differential data, and underpinned the need for experiments through the 50s, 60s, 70s and 80s. Data from experimental campaigns were routinely incorporated into nuclear data libraries either through changes to general nuclear data libraries, or more commonly in the local libraries generated by a particular institution or consortium interested in accurately predicting a specific nuclear system (e.g. fast reactors) or parameters (e.g. fission gas release, yields). Over the last three decades, the model has changed. In tandem access to computing power and monte carlo codes rose dramatically. The monte carlo codes were well suited to computing k-eff, and owing to the availability of high quality criticality benchmarks and these benchmarks were increasing used to test the nuclear data. Meanwhile, there was a decline in the production of local libraries as new nuclear systems were not being built, and the existing systems were considered adequately predicted. The cost-to-benefit ratio of validating new libraries relative to their improved prediction capability was less attractive. These trends have continued. It is widely acknowledged that the checking of new nuclear data libraries is highly skewed towards testing against criticality benchmarks, ignoring many of the high quality reactor physics benchmarks during the testing and production of general-purpose nuclear data libraries. However, continued increases in computing power, methodology (GPT), and additional availability reactor physics experiments from sources such as the International Handbook of Evaluated Reactor Physics Experiments should result in better testing of new libraries and ensured applicability to a wide variety of nuclear systems. It often has not. Leveraging the wealth of historical reactor physics measurements represents perhaps the simplest way to improve the quality of nuclear data libraries in the coming decade. Resources at the Nuclear Energy Agency can be utilized to assist in interrogating available identify benchmarks in the reactor physics experiments handbook, and expediting their use in verification and validation. Additionally, high quality experimental campaigns that should be examined in validation will be highlighted to illustrate potential improvements in the verification and validation process.

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Ma, Yi Hua. "Dense Palladium and Perovskite Membranes and Membrane Reactors." MRS Bulletin 24, no. 3 (March 1999): 46–49. http://dx.doi.org/10.1557/s0883769400051915.

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The development of high-temperature processes and tighter environmental regulations requires utilization of efficient gas-separation processes that will provide high fluxes, high selectivity of separation, and the ability to operate at elevated temperatures. Dense inorganic membranes and membrane reactors are especially well suited for high-temperature reactions and separations, due in part to their thermal stability and high separation selectivity (in theory, infinite). Furthermore, membrane reactors offer an inherent advantage of combining reaction, product concentration, and separation in a single-unit operation for the improvement of process economics and waste minimization.The classification of membrane reactors can either be by membrane material and geometry or by the configuration of the reactor. Porous and dense membranes in both tubular and disk forms have been used for membrane reactors. The membrane can either be catalytically active (catalytic membrane reactor [CMR]) or simply act as a separation medium. In the latter case, the catalyst is packed in the reactor, whose walls are formed by the membrane (packed-bed membrane reactor [PBMR]). In addition, if the membrane is also catalytically active, the reactor is called a packed-bed catalytic membrane reactor (PBCMR).The principal materials from which porous inorganic (ceramic) membranes are made are alumina, zirconia, and glass. Alumina and zirconia membranes are usually asymmetric and composite, with a porous support (0.5–2.0 mm thick) for mechanical strength and one or more thin layers for carrying out separations.On the other hand, glass membranes, such as Vycor and microporous glass, have symmetric pores. Materials commonly used as the porous support are alumina, granular carbon, sintered metal, and silicon carbide.

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44

Fukaya, Y., M. Goto, S. Nakagawa, K. Nakajima, K. Takahashi, A. Sakon, T. Sano, and K. Hashimoto. "REACTOR PHYSICS EXPERIMENT IN A GRAPHITE-MODERATION SYSTEM FOR HTGR." EPJ Web of Conferences 247 (2021): 09017. http://dx.doi.org/10.1051/epjconf/202124709017.

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The Japan Atomic Energy Agency (JAEA) started the Research and Development (R&D) to improve nuclear prediction techniques for High Temperature Gas-cooled Reactors (HTGRs). The objectives are to introduce a generalized bias factor method to avoid full mock-up experiment for the first commercial HTGR and to introduce reactor noise analysis to High Temperature Engineering Test Reactor (HTTR) experiment to observe sub-criticality. To achieve the objectives, the reactor core of graphite-moderation system named B7/4”G2/8”p8EUNU+3/8”p38EU(1) was newly composed in the B-rack of Kyoto University Critical Assembly (KUCA). The core is composed of the fuel assembly, driver fuel assembly, graphite reflector, and polyethylene reflector. The fuel assembly is composed of enriched uranium plate, natural uranium plate and graphite plates to realize the average fuel enrichment of HTTR and it’s spectrum. However, driver fuel assembly is necessary to achieve the criticality with the small-sized core. The core plays a role of the reference core of the bias factor method, and the reactor noise was measured to develop the noise analysis scheme. In this study, the overview of the criticality experiments is reported. The reactor configuration with graphite moderation system is rare case in the KUCA experiments, and this experiment is expected to contribute not only for an HTGR development but also for other types of a reactor in the graphite moderation system such as a molten salt reactor development.

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Goto, T., T. Tanaka, H. Tamura, J. Miyazawa, A. Iwamoto, N. Yanagi, T. Fujita, R. Kodama, and Y. Mori. "Feasibility study of tokamak, helical and laser reactors as affordable fusion volumetric neutron sources." Nuclear Fusion 61, no. 12 (November 15, 2021): 126047. http://dx.doi.org/10.1088/1741-4326/ac3367.

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Abstract The applicability of tokamak, helical and laser fusion reactors as a volumetric fusion neutron source has been examined using the systems codes that have been utilised for the conceptual design of DEMO and commercial reactors in Japan. This study has clarified the characteristics of reactor-based volumetric neutron sources that can be designed based on the current physics and engineering basis with a reasonable running cost (∼5B Yen/year). Although the achievable neutron flux is 2–3 orders lower than that of accelerator driven neutron sources, tokamak and helical neutron sources can provide a much larger irradiation area for the test of large components. Laser neutron sources have both high operability and tritium breeding capacity. These reactor-based neutron sources also serve as an integrated test bed of the entire reactor system.

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Chiba, Go, and Akio Yamamoto. "Mission of Reactor Physics." Journal of the Atomic Energy Society of Japan 61, no. 4 (2019): 254–56. http://dx.doi.org/10.3327/jaesjb.61.4_254.

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Qian, Xin, and Jen-Chieh Peng. "Physics with reactor neutrinos." Reports on Progress in Physics 82, no. 3 (February 25, 2019): 036201. http://dx.doi.org/10.1088/1361-6633/aae881.

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TAKEDA, Toshikazu, Shinya KOSAKA, Masahiro TATSUMI, Koichi SAKURADA, Shigeaki OKAJIMA, Akiko YAMAMOTO, Shunichi IDA, et al. "Contribution of Reactor Physics in Past and Future ; Is Reactor Physics Useful?" Journal of the Atomic Energy Society of Japan / Atomic Energy Society of Japan 45, no. 2 (2003): 85–111. http://dx.doi.org/10.3327/jaesj.45.85.

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Eberhardt, Klaus, and Christopher Geppert. "The research reactor TRIGA Mainz – a strong and versatile neutron source for science and education." Radiochimica Acta 107, no. 7 (July 26, 2019): 535–46. http://dx.doi.org/10.1515/ract-2019-3127.

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Abstract The TRIGA Mark II-reactor at the Johannes Gutenberg University Mainz (JGU) is one of three research reactors in Germany. The TRIGA Mainz became first critical on August 3rd, 1965. It can be operated in the steady state mode with a maximum power of 100 kWth and in the pulse mode with a peak power of 250 MWth and a pulse length of 30 ms. The TRIGA Mainz is equipped with a central thimble, a rotary specimen rack, three pneumatic transfer systems, four beam tubes, and a graphite thermal column. The TRIGA Mainz is intensively used both for basic and applied research in nuclear chemistry and nuclear physics. Two sources for ultra-cold neutrons (UCN) are operational at two beam ports. At a third beam port a Penning-Trap for highly precise mass measurements of exotic nuclides is installed. Education and training is another main field of activity. Here, various courses in nuclear and radiochemistry, reactor operation and reactor physics are held for scientists, advanced students, engineers, and technicians utilizing the TRIGA Mainz reactor.

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Li, Penglei, Lingen Chen, Shaojun Xia, and Lei Zhang. "Entropy Generation Rate Minimization for Methanol Synthesis via a CO2 Hydrogenation Reactor." Entropy 21, no. 2 (February 13, 2019): 174. http://dx.doi.org/10.3390/e21020174.

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The methanol synthesis via CO2 hydrogenation (MSCH) reaction is a useful CO2 utilization strategy, and this synthesis path has also been widely applied commercially for many years. In this work the performance of a MSCH reactor with the minimum entropy generation rate (EGR) as the objective function is optimized by using finite time thermodynamic and optimal control theory. The exterior wall temperature (EWR) is taken as the control variable, and the fixed methanol yield and conservation equations are taken as the constraints in the optimization problem. Compared with the reference reactor with a constant EWR, the total EGR of the optimal reactor decreases by 20.5%, and the EGR caused by the heat transfer decreases by 68.8%. In the optimal reactor, the total EGRs mainly distribute in the first 30% reactor length, and the EGRs caused by the chemical reaction accounts for more than 84% of the total EGRs. The selectivity of CH3OH can be enhanced by increasing the inlet molar flow rate of CO, and the CO2 conversion rate can be enhanced by removing H2O from the reaction system. The results obtained herein are in favor of optimal designs of practical tubular MSCH reactors.

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Journal articles on the topic 'Reactor physic'

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