Design Of System Components Research Articles

Promoting best practices in ocean forecasting through an Operational Readiness Level

Predicting the ocean state in a reliable and interoperable way, while ensuring high-quality products, requires forecasting systems that synergistically combine science-based methodologies with advanced technologies for timely, user-oriented solutions. Achieving this objective necessitates the adoption of best practices when implementing ocean forecasting services, resulting in the proper design of system components and the capacity to evolve through different levels of complexity. The vision of OceanPrediction Decade Collaborative Center, endorsed by the UN Decade of Ocean Science for Sustainable Development 2021-2030, is to support this challenge by developing a “predicted ocean based on a shared and coordinated global effort” and by working within a collaborative framework that encompasses worldwide expertise in ocean science and technology. To measure the capacity of ocean forecasting systems, the OceanPrediction Decade Collaborative Center proposes a novel approach based on the definition of an Operational Readiness Level (ORL). This approach is designed to guide and promote the adoption of best practices by qualifying and quantifying the overall operational status. Considering three identified operational categories - production, validation, and data dissemination - the proposed ORL is computed through a cumulative scoring system. This method is determined by fulfilling specific criteria, starting from a given base level and progressively advancing to higher levels. The goal of ORL and the computed scores per operational category is to support ocean forecasters in using and producing ocean data, information, and knowledge. This is achieved through systems that attain progressively higher levels of readiness, accessibility, and interoperability by adopting best practices that will be linked to the future design of standards and tools. This paper discusses examples of the application of this methodology, concluding on the advantages of its adoption as a reference tool to encourage and endorse services in joining common frameworks.

Numerical simulation of miniature high-speed aviation fuel pump using immersed solid method

Abstract Aviation fuel pumps are developing toward lightweight design and high rotational speeds at the same time that vehicles, such as missiles and unmanned aerial vehicles (UAVs), gradually get smaller. To investigate the internal flow field characteristics of a miniature aviation gear pump under conditions of high rotational speed, three-dimensional numerical simulations are conducted using computational fluid dynamics (CFD) software ANSYS CFX. The simulations use the immersed-solid method and employ the SST k-ω turbulence model. The findings reveal that under identical conditions, augmenting the tooth width by 1mm leads to a notable 27.32% increase in the average outlet flow rate and a corresponding enhancement of 7.22% in maximum efficiency. Furthermore, a 2mm increment in tooth width results in a substantial surge of 62.74% in the average outlet flow rate and a significant enhancement of 14.61% in maximum efficiency. Nevertheless, concurrently, the augmentation of tooth width corresponds with a gradual rise in trapped oil pressure and significant deterioration of the internal flow field. The study findings offer valuable insights into the integrated design of the oil supply system and engine components of aerospace engines.

Optimal design and analyzing the techno-economic-environmental viability for different configurations of an autonomous hybrid power system

In the present day, there is widespread acceptance of autonomous hybrid power systems (AHPSs) that rely on renewable energy sources (RESs), owing to their minimal adverse effects on the environment. This paper evaluates and compares three various AHPS configurations comprising photovoltaic (PV) modules, wind turbines (WTs), batteries, and diesel generators (DGs), using a recent optimization approach. A new optimizer 'Dandelion-Optimizer' (DO) is applied to tackle design problems. Real-time meteorological data from Siwa Oasis in northwest Egypt was utilized to determine an optimum design of system components for the purpose of providing sustainable power to this remote region. The system configurations are effectively modelled and optimized to achieve the minimum cost of energy (COE), while also minimizing the loss of power supply probability (LPSP) and carbon dioxide (CO2) emissions. As per the results, the last configuration (PV with both backup equipment) is the most optimal one in terms of the lowest cost, whereas the first configuration (PV and WT with both types of backup equipment) is the most optimal one with regards to the lowest carbon emissions.

Optimizing the Design of a Dry-Type Single Phase Gapped-Core Shunt Reactor to Empower National Industries

The import dependency of essential components in our country's electrical power system poses a significant challenge, emphasizing the importance of focusing on the design, development, and maintenance of power system components, particularly shunt reactors, from an economic standpoint. Domestic production of these components contributes to employment opportunities and enhances self-sufficiency. This study aims to address these challenges by optimizing the design of a dry-type single phase gapped-core shunt reactor with a rating of 100 kVAr and 10 kV. The reactor operates at a frequency of 50 Hz and experiences a maximum core flux density of 1.2 T. The study thoroughly examines the fundamental aspects related to the design of gapped-core shunt reactors. An optimal design is achieved by determining the optimal ratio of the cross-sectional area to the height of each core disk, employing a MATLAB code to minimize the reactor's initial manufacturing cost (IC) or losses. In addition, the proposed design undergoes simulation and analysis using the finite element method (FEM) in the MAXWELL software. The reactor's inductance is obtained through both Maxwell three-dimensional (3D) simulation and analytical methods, demonstrating a reasonable agreement that validates the effectiveness and reliability of the proposed approach.

Multi-objective optimization and configurations comparison of closed-air Brayton cycle

The microreactor power system is distinguished by its efficiency, compactness, and remarkable environmental adaptability. In this study, closed-air Brayton cycle (CABC) is proposed as the microreactor thermoelectric conversion system, and thermodynamic model of CABC with different configurations are established. The design of cycle parameters and component structures is accomplished through a combined system-component design approach. To obtained the optimal system design, the genetic algorithm and nondominated sorting genetic algorithm II are separately employed for single-objective and multi-objective optimization. In accordance with the results of multi-objective optimization, the intercooling reheat recuperative cycle attains the highest cycle efficiency at 35.4% and a power to mass ratio of 59.1 kW t−1. Conversely, the reheat recuperative cycle achieves the highest power density at 179.6 kW m−3 and its simpler structure renders it the optimal configuration for CABC. In comparison to single-objective optimization, the design results of multi-objective optimization exhibit a more balanced performance across three key indicators, signifying a superior overall performance of the optimized design scheme.

(Invited) Reach for the Sky: Solid Oxide Fuel Cell Hybrid Systems Enable Carbon-Neutral Flight in ARPA-E’s REEACH Program

The carbon-neutral economy of 2050 may rely on several sustainable fuels, including hydrogen, ammonia, and renewable hydrocarbons. Solid Oxide Fuel Cells (SOFCs) deliver value for each candidate carbon-neutral fuel thanks to their inherent fuel flexibility and high efficiency. This talk examines the additional benefits that can be realized in hybrid systems comprised of an SOFC with an engine bottoming cycle. Developments in ARPA-E’s REEACH program involving SOFC-turbogenerator hybrids for electrified flight will be discussed. The interplays between design and operation of system components can significantly impact the energy storage and power generation (ESPG) system metrics. Modeling work has been performed to inform hybrid system design and will be presented. Finally, next steps for hybrid system deployment at commercial scale will be discussed.

Thermal stabilization and energy harvesting in a solar PV/T-PCM-TEG hybrid system: A case study on the design of system components

In PV cells consisting of p-type and n-type semiconductor materials, electricity is produced with part of the solar radiation coming to the cell surfaces, while the rest causes the cells to rise in temperature, thus decreasing the conversion efficiency. Therefore, controlling the cell temperature is very important in terms of conversion efficiency. In this paper, passive cooling was performed by storing the heat acting on the PV panel with a 40 W harvesting capacity in the phase change material (PCM) in contact with the back surface. Simultaneously, active cooling was achieved by transferring the heat stored in the PCM to the hot-side surface of the integrated thermoelectric generator (TEG) with the help of the heat transfer fluid circulated in the copper pipes inside the PCM. Thus, the base hybrid system (PV/T-PCM-TEG) design (Case_1), which increases thermal stabilization of cells, was realized. While 20 thermoelectric modules are used in TEG, RT55 paraffin wax is used as PCM in the empty space on the back surface of the PV panel. In addition, to improve the PV/T-PCM-TEG system efficiency, three different cases were created by adding Al2O3 nanoparticles into the PCM (Case_2) and by placing copper fins around the copper pipes (Case_3). As a result, the power output of PV/T-PCM-TEG is 10.29%, 12.73%, and 14.22% higher for Case_1, Case_2, and Case_3, respectively, than the standard PV panel. In addition, the maximum PV panel efficiency is 30%, while the efficiency of PV/T-PCM-TEG increased to 32.8% with Case_1, 33.9% with Case_2, and 35.2% with Case_3.

Graph-based data management system for efficient information storage, retrieval and processing

Data management systems rely on a correct design of data representation and software components. The data representation scheme plays a vital role in how the data are stored, which influences the efficiency of its processing and retrieval. The system components design realizes software engineering concepts to enable performance metrics such as scalability, efficiency, flexibility, maintainability, and extendibility. This paper presents a data management system that uses a graph-based data representation scheme to achieve an efficient data retrieval when using graph-based databases. Input data are transformed into vertices, edges, and labels while inserting them into the database. The proposed system consists of three layers which are: system beans layer, data access layer, and the database engine. Healthcare data are used to evaluate the system in comparison with resource description framework (RDF) semantics. Extensive experiments are conducted to compare different scenarios of data storage and retrieval using Neo4J, OrientDB, and RDF4J. Experimental results show that the performance of the proposed graph-based approach outperforms RDF4J framework in terms of insertion and retrieval time.

A new statistical approach to identify critical mass flow rate in CO2 nozzles near saturation conditions

The pressing needs to increase efficiency in heat pumps require refined design of various system components. In common reverse cycles, the throttling valve performs pure energy dissipation, and therefore it is well suited to be replaced by technologies such as ejectors and turbines, to augment system performance. In both two-phase turbines and two-phase ejectors a supersonic convergent-divergent nozzle is commonly required, which is responsible for accelerating the refrigerant fluid from the high-pressure part (e.g. condenser) to the low pressure part (e.g. evaporator). In the design phase of these nozzles, the accurate prediction of the maximum mass flow rate, also known as the critical mass flow rate, is particularly complex due to the two-phase nature of the expansion. In this paper, a new statistical approach to determine the value of the critical mass flow rate for CO2, as refrigerant fluid, is presented and assessed. This approach is based on the MF (Massflow Factor) parameter, which well correlates the value of mass flow rate in sonic conditions. The relationship shown here is based on open experimental information and it is validated on data from the open literature and the industry. The relative error on critical flow rate is less than 15% in the validation range, placing this statistical approach at a level of accuracy comparable to other physical models. An example of design is provided in this paper to demonstrate the potential of the relationship found. This approach provides the designer with a straightforward and validated basis for a reliable preliminary design of expanding two-phase nozzles.

Review of liquid desiccant air dehumidification systems coupled with heat pump: System configurations, component design, and performance

Vapor Compression Systems (VCS) are the most common air conditioning technology. VCS cool the air to its dew point temperature (overcooling) to remove water vapor in the air through condensation and then reheats the air back to the comfort temperature for direct use. The VCS process is inefficient due to overcooling and reheating. Liquid Desiccant Dehumidification (LDD) is a potentially energy-efficient air conditioning. LDD removes water vapor in the process air using liquid desiccant’s high-water affinity. It hybrids with sensible cooling to control temperature and humidity separately. The LD in the LDD becomes weak after dehumidification. The LDD needs additional heating to regenerate the weak Liquid Desiccant (LD) to a high concentration for dehumidification.Earlier versions of the LDD systems use highly concentrated liquid desiccant (large water removal capability) to dehumidify the air by only dealing with latent load. It leads to highly elevated temperatures above 60 °C of heat sources (combustion or electric resistance-based heating) for regeneration. The energy needed for the elevated temperature heat resource significantly reduces or demolishes the benefit of LDD systems. In the recent two decades, researchers have investigated a new configured LDD system that couples an LDD with a heat pump at both dehumidification and regeneration sides for better efficiency.The heat pump provides cooling (from the evaporator) for both dehumidification and sensible cooling and simultaneous heating from the condenser for regeneration. The highly integrated system (HP-LDD) with improved efficiency enables the LDD to operate at lower concentrations and temperatures in dehumidification and regeneration.This paper depicts the working principle behind HP-LDD and its heating and cooling requirements. It reviews the comparison between the HP-LDD systems and the conventional LDD systems regarding system configurations, component design, energy efficiency, and dehumidification performance characteristics. The main findings from the review include the preferred use of packed bed over membrane-based dehumidifiers, the use of internally cooled dehumidifiers enabled by the HP cooling capacity, the high dispersion of HP operation conditions, and the dependence of dehumidification performance on various dehumidifiers. An outlook for future research on HP-LDD strategies is presented based on the reviewed works and their limitations.

METHODS AND MODELS OF RESEARCH OF INVESTMENT ATTRACTIVENESS AND COMPETITIVENESS OF PROJECT-ORIENTED ENTERPRISE IN THE PROCESS OF CREATING INNOVATIVE HIGH-TECH

The subject of the research is the investment attractiveness of enterprises producing competitive products with modern component architecture. The aim of the article is to develop complex methods for research of investment attractiveness of projects on creation of new high-tech products with component architecture. Tasks to be solved are: to use component method for the analysis of innovativeness of created high-tech products; to study investment attractiveness of an innovation project with the use of expert assessments and the method of planning experiments; to substantiate the composition of a diversification project portfolio for investment taking into account the limited possibilities of the enterprise based on the method of integer optimization; to study the performance of the project portfolio using agent-based imitational modeling. Methods used are: system analysis, component design, multi-criteria optimization, expert assessment and agent-based simulation modeling in the form of applied information technology. The results have been obtained: the analysis of investment attractiveness of projects on creation of new high-tech products with component architecture is carried out. The architecture of a complex product built with components from previous positive development experience is investigated. A classification of possible components in the architecture of a complex product is created. A set of indicators for assessing the investment attractiveness of an innovative component-based product is formed. The qualitative assessments of experts for the main indicators of the component composition of the product in the form of linguistic variables are proposed. The use of multifactor experiment to assess the investment attractiveness of a project to create a complex product with a component-based architecture is proposed. An optimization model for selecting the rational composition of components in an innovative product is developed. An agent-based simulation model is built to study the performance of work on the preparation of production of innovative products on a component basis. Conclusions: The use of a set of developed methods and applied information technology for the creation of high-tech products with component-based architecture allows you to plan a diversification portfolio of projects with investment attractiveness and competitiveness of products.

Analysis-Based Key Components Selection of Latent Heat Thermal Energy Storage System Along With Active Heat Transfer Enhancement

Abstract Energy storage is an effective approach to bridging the gap between energy supply and demand created due to the sporadic nature of solar energy. Thermal performance enhancement is a key research subject for effective energy storage using latent heat thermal energy storage (LHTES) systems. This paper focuses on the analysis-based design of suitable LHTES system components for solar absorption-based cooling applications with a working temperature of up to 200 °C. Initially, the medium-temperature range (80 °C to 200 °C) phase change material (PCM) is selected using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). Further, a suitable heat transfer fluid (HTF) is selected along with the design of a geometrical assessment and an appropriate LHTES system. Finally, the effect of the stirrer on the thermal performance of the LHTES system has been discussed. The melting time of PCM reduces by 58% while input energy increases by 20 kJ with an increase in HTF inlet temperature from 180 °C to 190 °C. However, input energy increases faster with a further increase in HTF inlet temperature while melt time does not reduce significantly. Therefore, selecting optimum HTF inlet temperature is an important criterion for efficient LHTES system design. Implanting a rotating stirrer at 200 RPM inside a PCM tube decreases the net-input energy by 73 kJ. Using back-of-the-envelope calculations, the analysis-based selection of key components of the LHTES system will pave the way forward to designing an application-specific LHTES system. Further, this study can be instrumental in theoretically scrutinizing the stirring effect on PCM charging before experimental analysis.

Architectural and Urban Planning Solutions for the Protection of Heritage Buildings in the Context of Terrorist Attacks: Following the Example of Passive Protection Systems

Events in recent years showing numerous terrorist attacks raise awareness regarding the necessity of considering the safety of heritage buildings. The analysis of available data allows us to conclude that it is not possible to fully prevent terrorist attacks. On the other hand, it is possible to minimize the impact of such incidents through proper design of passive protection system (PPS) components. One possible architectural solution to be deployed as a passive defense system is laminated glass panel walls. The study presented in this article is innovative, considering there are no current standard documents or recommendations to determine the conditions of destruction as well as the methods of testing the strength of glass components used in laminated glass panel walls under vehicle impact. The present work represents the material used in PVB interlayers using the Mooney–Rivlin constitutive model, which correctly describes the non-linear characteristics of PVB. Based on the obtained results, new parameters of PVB laminated glass exposed to vehicle impact were developed. The newly developed parameters underwent quality verification through a comparison of results from experimental studies and numerical simulations. Finally, the strength of laminated glass panel walls was subject to evaluation, considering the amount and thickness of individual VSG glass layers and the number of PVB interlayers at ground floor level of a heritage building with high susceptibility to terrorist attacks. The newly developed parameters of laminated glass may be implemented as a premade input .mat file for the material available in the KEYWORD database under the name MAT_32-LAMINATED_GLASS in the LS-DYNA software.

Design and characterization of a 3D printed miniature actuator using shape memory alloy wires

Microfluidics has been at the center of attention in chemical and biological sciences over the last decade since it can miniaturize many laboratory-based applications. However, the transition from concept to a practical microfluidic chip is greatly hindered due to the widespread conventional soft lithography techniques which are used for the fabrication of the microfluidic chips. These methods are not time- and cost-efficient. Additive manufacturing technique (i.e. 3D printing) has grown in many research fields. Many conventional microfluidic system component designs have been adapted to the 3D printing manufacturing techniques. Three-dimensional printed active components such as microvalves and micropumps have also been studied, however, almost all the designs depend on an external pneumatic control unit or syringe pumps so far. In this study, we aimed to address the lack of a microfluidic active component with an integrated actuator unit. We used a shape memory alloy as the actuator. In doing so, we employed an innovative batch fabrication method that utilizes 3D printing. The proposed actuator design can produce high work and concurrently isolate the heat source from the fluidic sample which is of utmost importance for biological samples. The results show that the miniature actuator can block high pressure (up to 150 mmHg) silicone channel partially or completely depending on the application requirements. The actuation time can be controlled electronically and reduced to times as low as 100 ms. In conclusion, this design proved to be a promising candidate for the development of flow control components such as microvalves, micropumps, or micromixers.

Quantification of vertical, lateral, and longitudinal fastener demand in broken spike track: Inputs to mechanistic-empirical design

To address a recent challenge related to broken spikes in premium elastic fastening systems that have led to at least ten derailments and require manual walking inspections as well as build upon mechanistic-empirical (M-E) design principles for future fastening system component design, this paper quantifies the vertical, lateral, and longitudinal fastening system loads under revenue service traffic in a curve that has regularly experienced spike fastener fatigue failures. Previous data has indicated that the high rail of Track 3 experienced the most failures at this location. The data from this investigation sheds light into why failures are more predominant at this location than others and how the vertical, lateral, and longitudinal loads cannot be considered independently. Specifically, while the magnitude of the applied loading was the lowest on the high rail of Track 3, the threshold for failure was also the lowest given the operations at this location led to unloading of the high rail, thus indirectly highlighting the importance of friction within a fastening system. The data also show the high rail of Track 3 was subjected to the highest L/V load ratios and was an outlier in the typical lateral load reversals applied likely leading to spike stress reversals and thus a shorter fatigue life. Finally, based upon the data, it is recommended that to mitigate spike failures, as well as similar fastener challenges in other track types (e.g. rail seat deterioration, etc.) railroads should ensure trains operate close to the balance speed and use fastening system that transfer loads through friction. This study also provides novel data for M-E design of fastening systems.

The development of a techno-economic model for the assessment of the cost of flywheel energy storage systems for utility-scale stationary applications

Flywheel energy storage systems are increasingly being considered as a promising alternative to electro-chemical batteries for short-duration utility applications. There is a scarcity of research that evaluates the techno-economic performance of flywheels for large-scale applications. Evaluating the capital cost, levelized cost of storage, and scale factor is crucial to make an informed decision in future development and deployment of the technology. This study, therefore, focuses on developing a bottom-up techno-economic model to design system components and to evaluate the total investment cost and levelized cost of storage of flywheels with a capacity of 20 MW/5 MWh for frequency regulation. Two rotor configurations were considered: composite rotor flywheel and steel rotor flywheel. The total investment costs of the composite rotor and steel rotor flywheel storage systems are $25.88 million and $18.28 million, respectively. The corresponding levelized costs of storage are $189.94/MWh and $146.41/MWh. The model results are highly sensitive to the cost of the rotor material, discount rate, factor of safety, number of cycles per year, and tensile strength of the rotor material. The ranges obtained in the uncertainty analysis for the levelized cost of storage are $122.08-$253.52/MWh and $108.63-$187.64/MWh for the composite rotor and steel rotor flywheel storage systems, respectively.

External function for GOTHIC code to estimate critical heat flux conditions for in-vessel retention assessment

GOTHIC is an integrated, general purpose thermal hydraulic software package for design, licensing, safety and operating analysis of Nuclear Power Plant containments, confinement buildings and system components. It bridges the gap between the lumped parameter codes frequently used for containment analysis (such as MELCOR, MAAP, COCOSYS, ASTEC codes) and Computational Fluid Dynamics codes. Within a single model, GOTHIC can include regions treated in conventional lumped parameter mode and regions with three-dimensional flows in complex geometries. The heat transfer correlations built into GOTHIC cover the portion of the boiling curve which spans single phase heat transfer up to pre-Critical Heat Flux (CHF) heat transfer. The implemented boiling curve is truncated to exclude post-CHF heat transfer as it has not been adequately verified and was considered by the developers to have little application in general containment analysis. As such, one area that the code is not currently qualified for is post-CHF heat transfer, which could occur for example in the case of In-Vessel Corium Retention, where cooling water enters in contact with the high temperature of the Reactor Pressure Vessel wall. The presented research focuses on creating an external subroutine that solves this limitation, enabling the GOTHIC code to account for CHF phenomena. The modeling of CHF would be very useful in order to enable the code to simulate the external Reactor Pressure Vessel (RPV) Cooling , as well as other types of severe accidents or analyses where post-CHF simulation is required. Several subroutine function switches were implemented in order to facilitate its usage for different types of heat structures and correlations. The subroutine determines the CHF values based on either: the 2006 Groeneveld Look-up Tables, Lookup Tables for Large Diameter Vertical Tubes, Look-up Tables for Large Diameter Horizontal Tubes, or the correlation used by the MELCOR code for critical heat flux situations. It shall be noted that the developed subroutine and its implementation were performed without the need to have access to the GOTHIC source code. In a previous paper, the GOTHIC code was used to perform a containment safety analysis for the Atucha-I NPP (CNA-I) for an in-vessel retention type of analysis. Highly conservative vapour generating boundary conditions were used in order to simulate the boiling between the cavity water and the RPV surface, and to bypass the GOTHIC limitation. The newly developed subroutine was used for the analysis of two postulated Atucha-I in-vessel retention scenarios, a Large Break Loss Of Coolant Accident (LBLOCA) and a Station Black-Out (SBO), with the simulation of heat transfer between RPV and cavity water. Specifically for in-vessel retention situations, a separate user selectable option for the subroutine was developed, in which the Critical Heat Flux is determined based on experiments performed at the ULPU facility from the University of California, Santa Barbara, USA, which were combined with the 2006 Groeneveld Look-up Tables primarily in order to have a pressure dependence. This was performed because for the Atucha-I analysis, the pressure was higher than in the ULPU facility.

A reduction of Dynamic Fault Tree to a Simple Form

The dynamic fault tree expands fault tree by giving the design of complex system components’ actions and crossings. Because DFT is high grade design and simple to use it is proving a rising not fail through reliability researchers. Unluckily, an issue of problems as yet stays when we using DFT These problems are (1) There are no formalities, (2) restriction in symbolic analysis and thus sensitiveness to increasing the trouble, and (3) there is a few of modular type-structure. Chain of Markov (I/O-IMC) input/output formularization are used to analyse DFT. I/O-IMC have accurate semantics and are expansion of uninterrupted-time Markov chains with output and input conducts.

A study on sodium - the fast breeder reactor coolant

Sodium, the second alkali metal in the first group of periodic table is highly chemically reactive. Sodium is widely used in pharmaceutical industries to manufacture lifesaving medicines. Liquid sodium is an excellent reducing agent and heat transport medium, which makes it an important industrial material. The application of this element in liquid form at high temperature as a coolant in fast breeder nuclear reactors necessitated development of sodium technology. Physical, chemical and nuclear properties of sodium led to the choice of sodium as the universally accepted fast breeder reactor (FBR) coolant. The manufacturing of sodium is by electrolysis process. The design and manufacturing requirements of high temperature liquid sodium system components are successfully addressed. Special type of sensors needed for high temperature liquid sodium system are specifically designed and developed. Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam is involved in the development of sodium technology in India. Sodium technology is matured to an extent and around twenty FBRs with sodium as the coolant were constructed, commissioned and successfully operated all over the world. Five sodium cooled fast reactors are currently in operation including fast breeder test reactor (FBTR) in India. Prototype fast breeder reactor (PFBR) is in the advanced stage of commissioning at Kalpakkam. This review paper explains the choice of sodium as FBR coolant and gives highlights on the research and development took place in sodium technology all over the world especially in India with an aim to give an exposure to this technology to the academic community.

A Traveling Wave Thermoacoustic Engine—Design and Test

Abstract The demand for clean, sustainable, and cost-effective energy continues to increase due to global population growth and the corresponding use of consumer products. The provision of heat to a thermoacoustic prime mover results in the generation of an acoustic wave that can be converted into electrical power. Thermoacoustic devices offer highly reliable and transportable power generation with low environmental impact using a variety of fuel sources. This paper focuses on the design and testing of a single-stage, traveling-wave, thermoacoustic engine. The system configuration, component design, and integration of sensors will be described. Performance testing and system analysis show that for a 300 W heat source, the thermoacoustic machine generates a 54 Hz acoustic wave with a thermal efficiency of 7.8%. The system’s acoustic power output may be increased by 84% through improved heat exchanger design. Tuning of the acoustic system and optimization of the bi-directional turbine merit attention to realize an applicable waste heat energy harvesting system.