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Nuclear energy is of vital importance for the energy independence of countries. Therefore, some of the countries have given priority to nuclear energy investments. However, there are some risks in nuclear reactors. For this reason, some countries are uneasy about nuclear energy investments. Thorium-based nuclear power plants are also recommended to minimize these risks. It is possible to talk about many advantages of these power plants. However, there are some negative aspects to these investments. In this study, both positive and negative aspects of thorium-based nuclear power plants are discussed simultaneously. In this context, first, the literature was comprehensively examined, and seven different factors were determined. An analysis is then carried out using the DEMATEL method. It is concluded that the cost and uncertainties have the greatest weight. In addition, suitability and physical and chemical reasons are other significant items. The results obtained show that thorium-based nuclear power plants are not very efficient now. In this context, the costs of thorium-based nuclear reactors should be reduced by new research and development activities. Otherwise, the high-cost problem reduces the efficiency of these reactors. With the developing technology, it is necessary to reduce the high costs. If the costs cannot be reduced, financial sustainability of thorium-based nuclear reactors will not be possible, although there are many benefits.

To present dynamical analysis of axisymmetric and three‐dimensional (3D) simulations of a nuclear fluidized bed reactor. Also to determine the root cause of reactor power fluctuations.

We have used a coupled neutron radiation (in full phase space) and high resolution multiphase gas‐solid Eulerian‐Eulerian model.

The reactor can take over 5 min after start up to establish a quasi‐steady‐state and the mechanism for the long term oscillations of power have been established as a heat loss/generation mechanism. There is a clear need to parameterize the temperature of the reactor and, therefore, its power output for a given fissile mass or reactivity. The fission‐power fluctuates by an order of magnitude with a frequency of 0.5‐2 Hz. However, the thermal power output from gases is fairly steady.

The applications demonstrate that a simple surrogate of a complex model of a nuclear fluidised bed can have a predictive ability and has similar statistics to the more complex model.

This work can be used to analyze chaotic systems and also how the power is sensitive to fluctuations in key regions of the reactor.

The work presents the first 3D model of a nuclear fluidised bed reactor and demonstrates the value of numerical methods for modelling new and existing nuclear reactors.

The purpose of this paper is to review the applications of the chemical reactor network (CRN) approach for modeling the combustion in gas turbine combustors and classify the CRN construction methods that have been frequently used by researchers.

This paper initiates with introducing the CRN approach as a practical tool for precisely predicting the species concentrations in the combustion process with lower computational costs. The structure of the CRN and its elements as the ideal reactors are reviewed in recent studies. Flow field modeling has been identified as the most important input for constructing the CRNs; thus, the flow field modeling methods have been extensively reviewed in previous studies. Network approach, component modeling approach and computational fluid dynamics (CFD), as the main flow field modeling methods, are investigated with a focus on the CRN applications. Then, the CRN construction approaches are reviewed and categorized based on extracting the flow field required data. Finally, the most used kinetics and CRN solvers are reviewed and reported in this paper.

It is concluded that the CRN approach can be a useful tool in the entire process of combustion chamber design. One-dimensional and quasi-dimensional methods of flow field modeling are used in the construction of the simple CRNs without detailed geometry data. This approach requires fewer requirements and is used in the initial combustor designing process. In recent years, using the CFD approach in the construction of CRNs has been increased. The flow field results of the CFD codes processed to create the homogeneous regions based on construction criteria. Over the past years, several practical algorithms have been proposed to automatically extract reactor networks from CFD results. These algorithms have been developed to identify homogeneous regions with a high resolution based on the splitting criteria.

This paper reviews the various flow modeling methods used in the construction of the CRNs, along with an overview of the studies carried out in this field. Also, the usual approaches for creating a CRN and the most significant achievements in this field are addressed in detail.

The purpose of this paper is to describe cost effective structural design procedures to support catalytic reactors used in hydrocarbon industry. Three case studies are presented using various reactor models. Modularization and transportation challenges are also discussed. The scope of the paper is limited only to the structural and construction aspects. The chemical and mechanical designs are not covered in this paper.

Finite element strategies are developed to model load transfer to reactor’s supports and to simulate soil/structure interaction. Fictitious nodes are generated at bolt locations to transfer the reactor’s loadings from the skirt to the pile cap. Soil-pile interaction is modeled using horizontal and vertical springs along the pile embedded length. Flexible supports are used at the bottom of the piles to stimulate the end bearing of the soil bed. The approach is demonstrated for several case studies of reactors support system.

The described algorithm is accurate and computationally efficient. Furthermore, the procedure can be used in practice for design catalytic reactor support.

The paper provides very useful guidelines that can be utilized in practice for design of catalytic reactor supports system. The procedure is cost effective and computationally efficient.

Extensive efforts were made in the past to develop economical procedures for catalytic reactors design. Much of the work focused on the process and mechanical aspects of catalytic reactors. Very limited work addressed the structural design aspects. Furthermore, no guidelines are available in current codes of practice.

During the past ten years, anaerobic process has become a popular technology for treating concentrated effluents. Research and development programmes led by both engineers and microbiologists have resulted in a better understanding of the microbiology of anaerobic reactions and reactor design for anaerobic processes. Considerable progress has been achieved in the development of high rate anaerobic reactors with several configurations for treating concentrated industrial effluents. In this review, attention is paid to highlighting the conceptual and full scale developments of anaerobic fluidized bed reactors, in respect of process performance, design concepts, start‐up of the reactor, stability of the system with respect to various operating parameters, reactor configurations, comparison with competing reactor designs for concentrated industrial effluents and kinetics and modelling of reactor systems.

This paper presents a novel concept for design of concrete support system for chemical reactors used in refineries and petrochemical plants. Graphical method is described that can be used to size the concrete base and piling system. Recommendations are also provided to optimize the parameters required for the design. The procedure is illustrated for design of two reactor models commonly used in gas recovery units.

Design space representation for the foundation system is described for chemical reactors with variable heights. The key points of the design graph are extracted from the numerical finite element models. The reactor load is idealized at discrete points to transfer the loads to the piles. Bilateral spring system is used to model the soil restrains.

The graphical approach is economical and provides the design engineer the flexibility to select the foundation parameters from wide range of options.

The concept presented in the paper can be utilized by engineers in the industry for design of chemical reactors. It must be noted that little guidelines are currently available in practice addressing the structural design aspects.

A novel concept is presented in this paper based on significant industrial design experience of reactor supports. Using the described method leads to significant cost savings in material quantity and engineering time.

Carbonate-based heterogeneous reacting systems are investigated for the applications of thermochemical carbon dioxide capture and energy storage. This paper aims to review recent progress in numerical modeling of thermal transport phenomena in such systems.

Calcium oxide looping is selected as the model carbonate-based reacting system. Numerical models coupling heat and mass transfer to chemical kinetics are reviewed for solar-driven calcium oxide looping on the sorbent particle, particle bed, and reactor levels.

At the sorbent particle level, a transient numerical model of heat and mass transfer coupled to chemical kinetics has been developed for a single particle undergoing cyclic calcination and carbonation driven by time-periodic boundary conditions. Modeling results show cycle times impact the maximum sorbent utilization and solar-to-chemical energy efficiency. At the reactor level, a model of heat and mass transfer coupled to chemical kinetics of calcination of a packed-bed reactor concept has been developed to estimate the reactor’s performance. The model was used to finalize reactor geometry by evaluating pressure drops, temperature distributions, and heat transfer in the reactor.

Successful solar thermochemical reactor designs maximize solar-to-chemical energy conversion by matching chemical kinetics to reactor heat and mass transfer processes. Modeling furthers the understanding of thermal transport phenomena and chemical kinetics interactions and guides the design of solar chemical reactors.

The purpose of this paper is to review technologies for nuclear power and to assess their suitability in pursuit of clean, safe and secure energy independence.

Technologies and potentials associated with the industry standard, light water reactors (LWR), as well as fast breeder reactors and TRISO‐fueled reactors, are reviewed. The key features and issues include: waste disposal and toxicity, heat pollution, vulnerability to terrorist attack, proliferation of weapon materials, global fuel depletion, safety, and cost.

The paper finds that, on balance, TRISO‐fueled reactors with helium as coolant offer solutions to the issues causing public nuclear concerns, and since they have significant cost benefits they should be the design of choice for new installations.

Nuclear power can make a contribution to rising energy demands but raise many concerns. This paper considers the principal types of nuclear reactors and analyzes them for their potential to address those important public concerns.

The paper's aim is to suggest a new micro‐thermonuclear reactor for aerospace.

Methods of the thermonuclear physics are used for the research.

The result is new micro‐thermonuclear reactor with very small fuel pellet that uses plasma confinement generated by multi‐reflection of laser beam or its own magnetic field. The Lawson criterion increases by hundreds of times. The author also suggests a new method of heating the power‐making fuel pellet by outer electric current as well as new direct method of transformation of ion kinetic energy into harvestable electricity. These offered innovations dramatically decrease the size, weight and cost of thermonuclear reactor, installation, propulsion system and electric generator.

The author is researching the efficiency of these innovations for two types of the micro‐thermonuclear reactors: multi‐reflection reactor (inertial confinement fusion) and self‐magnetic reactor (magnetic confinement fusion).

The author offers several innovations. Results may be used for the design of thermonuclear aerospace engines, propulsion and electric generators.

Modularity in design and construction of nuclear power plants (NPPs) is widely used for reduction in project construction time and cost. This paper aims to improve understanding of existence, rationale, relevance, types and definitions of modularity in NPPs.

The paper approaches study of modularity in NPPs through review of existing literature. The objective of this paper is to answer the questions such as “what is the meaning of module in the context of NPPs?”, “what is the meaning of modularity in the context of NPPs?”, “why modularity is considered in the design and construction of NPPs?”, “what are the types of modules and modularity?” and “what are the emerging trends?”

Findings of the paper indicate towards widespread use of modularity to reduce construction time and cost, improve safety performance and enable smarter applications of NPPs. Large NPPs tend to use modularity to shorten the project gestation period, and thereby reduce capital cost. Small and medium size NPPs plan to use modularity for simpler and safer reactors that can be factory manufactured, transported, installed and scaled up as permitted by the economic environment.

This being a review, it has the usual limitations associated with the literature review papers.

Findings of the paper may influence policy regarding option, type, size, design, engineering, procurement and construction of NPPs.

Findings of the paper may influence the safety, cost, time and quality performance of future NPPs and facilitate cheaper and more reliable supply of electricity to consumers.

The systematic literature review presents issues and emerging trends in modularity of NPPs, enabling the future work to progress as modularity continues to develop and evolve. The paper also proposes a comprehensive classification and definitions of modules and modularity in NPPs that may facilitate understanding of these terms precisely and uniformly by researchers and practitioners alike.