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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.

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.

The purpose of this study is analysis on fluid flow characteristics inside a modified designed spiral bubble column photo-bioreactor. Available fluid dynamic simulation of bubble column reactor (BCR) (which is well-known conventional photobioreactor) had shown significance contribution over the past two decades, where the fluid dynamics of the culture medium and mixing will influence the average irradiance and the light regimen to which the cells are exposed. This enhances the growth. To develop this, and also to cut down the cost parameter involving the production of biodiesel from algae, the growth rate of algae has to be enhanced.

Some design modification through a staggered spiral-path inside the bubble column design had been proposed and comparative simulation of the modified design has been reported. Three-dimensional simulations of gas–liquid flow both in the BCR and spiral path column reactor have been carried out using the Euler–Euler approach. Various graphs are plotted, and from comparing, it has been seen that the proposed reactor will enhance better mixing rate, which could help the growth rate in microalgae in the present proposed model. In this paper, an earnest attempt had made to carry out computational simulation of conventional BCR and designed reactor used for cultivation of microalgae which had analyzed using commercial code ANSYS 14.

From this work, it was observed that the average turbulence kinetic energy fluctuates more in designed reactor over the conventional photo bioreactor, which will in turn increase diffusivity and enhance transfer of mass, momentum and energy. The results provide comprehensive information concerning effect of fluid flow characteristics inside a modified designed spiral bubble-column photo-bioreactor.

Some of our earlier published results (www.scientific.net/AMM.592-594.2427) are also referred in this paper. This work had been performed under the financial aid from RPS project (no. 8,023/RID/RPS/27/11/12), sponsored by All India Council for Technical Education.

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.

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.

To design a pulse power water treatment system, it is necessary to design a reactor optimally. One of the most essential types of reactors used in water treatment is the dielectric barrier discharge (DBD) reactor. The purpose of this paper is to model the electric field in the two types of planar and coaxial reactors to have an accurate analytical formula for using in the optimal design according to the required electric field of the treatment.

The method proposed in this paper focuses on the voltage of different areas in the reactor and different boundary conditions to obtain the surface charge density. In this regard, parameters of the dielectric and treated material, as well as the reactor dimension, have been affected in the equations. To confirm the analytical results, the finite element method simulation has been performed, and it shows the accuracy of this method.

The exact analytical equation of the electric field is found within the discharge zone of the planar and coaxial DBD reactors. These equations can predict the values of different parameters of the reactor required to purify the material before each design and it does not even require simulation.

The electric field formula presented in this paper can allow the manufacturers of pulse power water treatment systems to optimize their design easily, cost-effectively and in less time. Also, the formulas provided are completely general and remain effective for all materials.

This paper aims to investigate the major causes of the nuclear power plant (NPP) disasters since 1950, elucidates the commonalities between them and recommends strategies to minimize the risk of NPP disasters.

This paper analyzes facts from five case studies: Chernobyl disaster, USSR 1986; Fukushima Daiichi disaster, Japan 2011; Three Mile Island incident, USA 1979; Chalk River Accident, Canada 1952; and SL-1 Accident, USA 1961. A qualitative approach is adopted to compare and contrast the major reasons that led to the accidents, and consequent social and technological impacts of the disasters on environment, society, economy and nuclear industry are analyzed.

Although each of the nuclear accidents is unique in terms of its occurrence and impacts, this research study found some common causes behind the accidents. Faulty system design, equipment failure, inadequate safety and warning systems, violation of safety regulations, lack of training of the nuclear operators and ignorance from the operators and regulators side were found to be the major common causes behind the accidents.

This paper recommends some of the nuclear disaster risk reduction strategies in terms of “lessons learned from the past accidents”. The findings of the research paper would serve as an information tool for the nuclear professionals for informed decision-making and planning for proper preventive measures well in advance so that the mistakes which led to the occurrence of accidents in the past are not repeated in the future.

Construction work is due to start next month on Hanker Siddeley's first export Jason, ordered by the Dutch Reactor Centre near Amsterdam

The purpose of this paper is to consider a procedure of water-water energetic reactor (WWER) reactor pressure vessel (RPV) lifetime prediction at the stages of design and lifetime extension using the standard irradiation embrittlement parameters as defined in regulatory documents. A comparison is made of the brittle fracture resistance (BFR) values evaluated using two criteria: shift in the critical brittleness temperature ΔT_c or shift in the brittle-to-ductile transition temperature ΔT_p and without shifts (T_c and T_p).

The radiation resistance was determined using the following three approaches: calculation based on standard values ΔT_c and T_c0 or ΔT_p and T_p0 (a level of excessive conservatism); calculation based on standard value ΔT_c and actual value T_c0 or actual values ΔT_p and T_p0 (the level of realistic conservatism); or calculation based on actual values of T_c and T_c0 or T_p and T_p0 (the level of actual conservatism). The BFR was evaluated based on the results of testing the specimens subjected to irradiation in research reactors as well as surveillance specimens subjected to irradiation immediately under operating conditions.

The excessive conservatism in determining the actual lifetime of nuclear reactor vessel materials can be eliminated by using the immediate values of critical brittleness temperature and ductile-to-brittle transition temperature.

Obtained results can be applied to extend WWER vessel operating time at the stages of designing and operation due to substantiated decrease in conservatism. And it will allow carrying out a statistical substantiated assessment of the resistance to brittle fracture of the RPV steels.