Browsing by Author "Pagone, Emanuele"
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Item Unknown Advanced low carbon power systems - the advanced zero emissions power plant(Cranfield University, 2009-10) Pagone, Emanuele; Ogaji, S.The global warming issue is becoming more and more important in the public opinion, because its effects on everyday life of the entire mankind are starting to become appreciable. On the next (2009) December will be held in Copenhagen the fifteenth United Nations Climate Change Conference which is expected to be crucial for the future choices to deal with the anthropogenic greenhouse gases issue. The power generation sector is one of the most important contributors to the emissions of greenhouse gases (of which the carbon dioxide is the main anthropogenic example), and it is facing in the last decades a problem that will exacerbate surely the already alarming effect on the global warming: the rapid increase of the world power demand. For these reasons the carbon capture topic is gaining nowadays a lot of attention, especially in the industrial sector, since it will be a strategic field for the power generation in the short-medium term. In fact, it is really likely that will be introduced soon a so-called “cap and trade” system, with the trading of pollution licences related to the CO2 emissions, as the USA president Obama has recently proposed to the Congress. This option would turn out in a completely new scenario in the power generation sector with novel, cleaner concepts being economically more attractive than the conventional ones. This project investigates the performance of a novel thermodynamic cycle with carbon capture, called Advanced Zero Emissions Power plant (AZEP), which has been analysed in the open literature just partially and superficially up to now. Since this project is part of a bigger one in which several carbon capture novel cycles options will be compared, the main objective is to provide a flexible, modular, modern computational tool, called eAZEP, developed from scratch. The second objective is the evaluation of the four main layouts of the AZEP concept as a stand alone power plant, assessing their inclination to be included in an unfired combined cycle featured with an Heat Recovery Steam Generator (HRSG). A final, third objective is the development of a routine for the off-design performance calculation to be included in on old pre-existing computational tool. The original contribution of this work to the knowledge on the topic comprises 1. the conception of two new layouts for the AZEP cycle (the Post Expan-sion Heat exchanger layouts); 2. the performance evaluation of the long term potential for the power plant; 3. a sensitivity analysis of the thermodynamic concept. The best suitable arrangements of the plant layout are identified together with the main parameters which influence their performance, both for the combined cycle perspective implementation and for the stand alone option. Thanks to the flexibility of eAZEP will be easy to consider, in a future work, a pretty wide number of alternative concepts and investigate more cycle parameters in order to broaden the conclusions obtained in this work. Moreover the combined cycle off-design new routine must be debugged and validated.Item Open Access An approach to airline MRO operators planning and scheduling during aircraft line maintenance checks using discrete event simulation(Elsevier, 2021-07-30) Albakkoush, Salah; Pagone, Emanuele; Salonitis, KonstantinosThe process of scheduling and planning refers to examining aircraft history based on when and where the aircraft should go for service checks. In this paper, the authors focused on line maintenance activities and examined the impact of unexpected factors (Missing tools and safety requirements) on such activities during the process through a Discrete Event Simulation (DES) model. The DES was used to determine the following: 1. The plan time of each maintenance task according to maintenance scheduling based on the X airline company in Libya; 2. A tasks and productivity evaluation which involved examining the number of tasks required to do per check according to the scheduling plan and planned tasks performed by technicians, and; 3. The total elapsed time involved by analysing the average time for each task according to maintenance schedule planning. The results show that, for all scenarios conducted, the DES model was operating at a high level, and in some scenarios, there was a breakdown in service tasks; a clear indication that the workload factor was high during check periods. However, the main finding in this study highlights how a number of different tasks or the breakdown of maintenance work packages were not being completed before the actual time that had been allocated for the general external condition A-check of the aircraft. This made it necessary to study the work package for each check separately and examine these work packages as they relate to DES which presents a potential solution to a more efficient planning approach. This feature enhances the applicability of the proposed method in real-life, and helps airlines cope with the dynamic environment of airline MRO.Item Unknown Approach to value stream mapping for make-to-order manufacturing(Elsevier, 2020-09-22) Mudgal, Devanshu; Pagone, Emanuele; Salonitis, KonstantinosThis paper presents a new approach to the Value Stream Mapping (VSM), a proven tool of Lean Manufacturing (LM) in a Make-To-Order (MTO) manufacturing environment. The use of VSM in mass production has proven to be successful due to the predictable volume and repetitive product type. Within a MTO environment the product is tailored to specific requirements and varying volumes make it hard to balance production causing lean waste. The approach combines the classic VSM technique with commonality analysis to get a better understanding of the processes. Author illustrates this approach using a case study. Using VSM for MTO requires some changes to capture the attributes of product families required at different frequencies and volumes successfullyItem Open Access Automatically weighted high-resolution mapping of multi-criteria decision analysis for sustainable manufacturing systems(Elsevier, 2020-02-01) Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.A common feature of Multi-Criteria Decision Analysis (MCDA) to evaluate sustainable manufacturing is the participation (to various extents) of Decision Makers (DMs) or experts (e.g. to define the importance, or “weight”, of each criterion). This is an undesirable requirement that can be time consuming and complex, but it can also lead to disagreement between multiple DMs. Another drawback of typical MCDA methods is the limited scope of weight sensitivity analyses that are usually performed for one criterion at the time or on an arbitrary basis, struggling to show the “big picture” of the decision making space that can be complex in many real-world cases. This work removes all the mentioned shortcomings implementing automatic weighting through an ordinal combinatorial ranking of criteria objectively set by four pre-defined weight distributions. Such solution provides the DM not only with a fast, rational and systematic method, but also with a broader and more accurate insight into the decision making space considered. Additionally, the entropy of information in the criteria can be used to adjust the weights and emphasise the differences between potentially close alternativeItem Open Access Carbon footprint comparison of bitcoin and conventional currencies in a life cycle analysis perspective(Elsevier, 2023-04-18) Pagone, Emanuele; Hart, Alexandre; Salonitis, KonstantinosCryptocurrencies are a digital form of money based on the blockchain technology. Their relatively recent raise in popularity and use, together with the energy-intensive nature of some of their algorithms, has raised environmental concerns about growing energy consumption (and associated carbon dioxide emissions). This paper aims at comparing the environmental impact of the most common cryptocurrency (i.e., Bitcoin) and fiat currencies (i.e. coins, banknotes, credit and debit card networks). Such comparison is carried out assessing and analyzing the life cycle main phases of each currency in terms of carbon dioxide equivalent emissions. Results show that Bitcoin has a carbon footprint almost 4 to 5 times greater than the sum of all forms of traditional currency together in one year. Furthermore, environmental impact “hotspots” of fiat currency including raw material production of coins, transportation of banknotes and electric energy consumption of ATMs are identified. Finally, considering future scenarios and the sensitivity of various parameters on the results, some solutions are proposed to reduce the environmental impact of currencies.Item Open Access Comparative study of multi-criteria decision analysis methods in environmental sustainability(KES International, 2022-09-16) Pagone, Emanuele; Salonitis, KonstantinosMulti-Criteria Decision Analysis (MCDA) is an operations research framework used to support decision-makers in choosing alternatives characterized by multiple conflicting criteria. Over the past years, several MCDA methods have been developed and a significant drawback of using more than one algorithm for a given problem is the potential conflicting ranking that they may yield. This work aims at setting the first steps toward a systematic framework that reconciles different rankings from MCDA methods and returns to the decision maker a unique solution. The proposed method is contextualised within the existing scientific literature and illustrated considering four case studies to select environmentally sustainable solutions. Results show that a ranking agreed by multiple MCDA methods is more reliable than a ranking obtained by one method.Item Open Access A computational framework towards energy efficient casting processes(Springer, 2018-12-01) Papanikolaou, Michail; Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.; Makatsoris, MakatsorisCasting is one of the most widely used, challenging and energy intensive manufacturing processes. Due to the complex engineering problems associated with casting, foundry engineers are mainly concerned with the quality of the final casting component. Consequently, energy efficiency is often disregarded and huge amounts of energy are wasted in favor of high quality casting parts. In this paper, a novel computational framework for the constrained minimization of the pouring temperature is presented and applied on the Constrained Rapid Induction Melting Single Shot Up-Casting (CRIMSON) process. Minimizing the value of the pouring temperature can lead to significant energy savings during the melting and holding processes as well as to higher yield rate due to the resulting reduction of the solidification time. Moreover, a multi-objective optimization component has been integrated into our scheme to assist decision makers with estimating the trade-off between process parameters.Item Open Access Cradle-to-grave lifecycle environmental assessment of hybrid electric vehicles(MDPI, 2023-07-14) Rashid, Shafayat; Pagone, EmanueleDemand for sustainable transportation with a reduced environmental impact has led to the widespread adoption of electrified powertrains. Hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs) produce lower greenhouse gas (GHG) emissions during the use phase of their lifecycle, compared to conventional internal combustion engine vehicles (ICEVs). However, a full understanding of their total environmental impact, from resource extraction to end-of-life (EOL), of a contemporary, real-world HEV and PHEV remains broadly elusive in the scientific literature. In this work, for the first time, a systematic cradle-to-grave lifecycle analysis (LCA) of a Toyota Prius XW50, as a HEV and PHEV, was used to comprehensively assess its environmental impact throughout its entire lifecycle using established lifecycle inventory databases. The LCA revealed that the gasoline fuel cycle (extraction, refinement, and transportation) is a major environmental impact “hotspot”. The more electrified PHEV model consumes 3.2% more energy and emits 5.6% more GHG emissions within the vehicle’s lifecycle, primarily owed to the manufacturing and recycling of larger traction batteries. However, when factoring in the fuel cycle, the PHEV model exhibits a 29.6% reduction in overall cradle-to-grave life energy consumption, and a 17.5% reduction in GHG emissions, in comparison to the less-electrified HEV. This suggests that the higher-electrified PHEV has a lower environmental impact than the HEV throughout the whole lifecycle. The presented cradle-to-grave LCA study can be a valuable benchmark for future research in comparing other HEVs and PHEVs or different powertrains for similarly sized passenger vehicles.Item Open Access Defect minimisation in vacuum assisted plaster mould investment casting through simulation of high value aluminium alloy components(Springer, 2023-02-09) Pagone, Emanuele; Jones, Christopher A.; Forde, John; Shaw, William; Jolly, Mark; Salonitis, KonstantinosVacuum-assisted plaster mould investment casting is one of the best available processes to manufacture ultra-high complexity castings for the aerospace and defence sectors. In light of the emerging cross-sectoral manufacturing industry digitalisation, process simulation appears as a very important tool to improve casting yield, reduce metallurgical scrap, and reduce lead time to new product introduction. Considering the unique aspects and the level of customisation of the process system, this work will present a Computational Fluid Dynamics-based simulation tool with bespoke settings (that include thermophysical properties). Optimal fill and solidification parameters are identified for a representative geometry able to describe a variety of very complex, high-value aluminium alloy components through an iterative process.Item Open Access Design optimisation of the feeding system of a novel counter-gravity casting process(MDPI, 2018-10-11) Papanikolaou, Michail; Pagone, Emanuele; Georgarakis, Konstantinos; Rogers, Keith; Jolly, Mark R.; Salonitis, KonstantinosThe appropriate design of feeders in a rigging system is critical for ensuring efficient compensation for solidification shrinkage, thus eliminating (shrinkage-related) porosity and contributing to the production of superior quality castings. In this study, a multi-objective optimisation framework combined with Computational Fluid Dynamics (CFD) simulations has been introduced to investigate the effect of the feeders’ geometry on shrinkage porosity aiming to optimise casting quality and yield for a novel counter-gravity casting process (CRIMSON). The weighted sum technique was employed to convert this multi-objective optimisation problem to a single objective one. Moreover, an evolutionary multi-objective optimisation algorithm (NSGA-II) has been applied to estimate the trade-off between the objective functions and support decision makers on selecting the optimum solution based on the desired properties of the final casting product and the process characteristics. This study is one of the first attempts to combine CFD simulations with multi-objective optimisation techniques in counter-gravity casting. The obtained results indicate the benefits of applying multi-objective optimisation techniques to casting processesItem Open Access The development of a tool to promote sustainability in casting processes(Elsevier, 2016-11-02) Pagone, Emanuele; Jolly, Mark R.; Salonitis, KonstantinosThe drive of the manufacturing industry towards productivity, quality and profitability has been supported in the last century by the availability of relatively cheap and abundant energy sources with limited focus on the minimisation of energy and material waste. However, in the last decades, more and more stringent regulations aimed at reducing pollution and consumption of resources have been introduced worldwide and in particular in Europe. Consequently, a highly mature and competitive industry like foundry is expecting challenges that an endeavour towards sustainability can turn into significant opportunities for the future. A tool to undertake a systematic analysis of energy and material flows in the casting process is being developed. An overview of the computer program architecture is presented and its output has been validated against real-world data collected from foundries.Item Open Access Eco-social sustainability assessment of manufacturing systems: an LCA-based framework(Elsevier, 2023-04-18) Haddad, Yousef; Atescan Yuksek, Yagmur; Jagtap, Sandeep; Jenkins, Simon; Pagone, Emanuele; Salonitis, KonstantinosIn this paper, model-based sustainability assessment framework with social impact considerations is developed. The framework integrates the stochastic, nonlinear, and complex interrelationships that characterize most manufacturing systems, and incorporates their impact in the sustainability assessment module. The framework consists of three models that run successively, namely: stochastic discrete-event simulation (DES) model, environmental lifecycle assessment (LCA) and social LCA models. To test and validate the model, and to demonstrate its applicability and usefulness in industrial settings, a case study on the environmental and social impacts associated with the manufacturing of an aerospace component is carried out. Results revealed that integrating the stochastic behaviour of production systems can unveil production issues that are likely to arise at the strategic level and affect the sustainability performance, while not being instantly perceptible. Social LCA indicated that, although input data suffered from quality issues, there is a potential higher risk associated with overseas upstream supply chains. This risk can, however, be potentially mitigated through technology-based enhanced traceability and transparency of upstream supply chains, or even the localization of upstream activities, where possible.Item Open Access The effect of operational policies on production systems robustness: an aerospace case study(Elsevier, 2019-06-24) Pagone, Emanuele; Efthymiou, Konstantinos; Mahoney, Brandon; Salonitis, KonstantinosThis study aims to evaluate the robustness of a low volume mixed model production line under different operating conditions. A real production line that builds six different aircraft heat exchangers is modelled, simulated and analysed under different operating conditions. A number of experiments are conducted in order to assess the effect of dispatching rules and disturbances related to reworks, and processing time variance on tardiness robustness. A penalty function to quantitatively assess tardiness is defined based on lead time at capacity and it is used to measure the robustness of the system. The results of the assessment are then discussed in order to give some practical guidance to production planners with controlling the line in the face of uncertainty or disturbances similar to those evaluated in the study.Item Open Access Energy and material efficiency metrics in foundries(Elsevier, 2018-03-07) Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.Most of the current foundry processes are based on well-developed and established practices typical of mature technologies. Contemporary economic, environmental and societal developments have concurrently changed at an unprecedented rate the context where traditional metal casting methodologies have not really developed much over time. Consequently, significant challenges and opportunities arise. This work will present the founding metrics of a novel approach to metal casting with the development of a new philosophy (called “Small is Beautiful”) aimed at tackling the current pressures on the industry with a focus on energy and materials’ efficiencies and flexible production. Traditional and well-established parameters are presented and compared to new metrics defined from first principles and thermodynamic properties. All metrics are validated using industrial and scientific literature data of five sand casting plants melting different ferrous and non-ferrous alloys.Item Open Access Energy efficiency status-quo at UK foundries: the “small-is-beautiful” project(Springer, 2017-02-12) Jolly, Mark R.; Salonitis, Konstantinos; Charnley, Fiona; Ball, Peter D.; Ahmad Mehrabi, Hamid; Pagone, EmanueleItem Open Access Energy efficiency status-quo at UK foundries: the “small-is-beautiful” project(Springer, 2017-02-12) Jolly, Mark R.; Salonitis, Konstantinos; Charnley, Fiona; Ball, Peter; Mehrabi, Hamid; Pagone, EmanueleEnergy efficiency is a critical issue for all manufacturing sectors. In the present paper the energy efficiency of UK foundries was assessed. In the context of this research 80 foundries were studied, 60 were contacted and 10 were visited. General energy data were collected using structured questionnaires, interviewing energy managers and process operators. A number of foundries are operating to a good standard, by employing energy managers and regularly auditing; they are in control of their process and working rigorously to improve their efficiency. Simultaneously though, smaller foundries have not adjusted to the new market demands and are not operating in the most energy efficient manner. Important barriers to energy efficiency in these foundries include lack of knowledge on auditing methods, poor knowledge in managing energy consumption, the inefficiency of individual process steps, production disruptions, aging equipment, personnel behavior, inadequate maintenance and lack of investment, automation and research.Item Open Access Energy resilient foundries: the “Small is beautiful” projects(Springer, 2022-02-05) Jolly, Mark R.; Salonitis, Konstantinos; Pagone, Emanuele; Papanikolaou, Michail; Saxena, PrateekApplying the concept of “small is beautiful” into a conservative relatively low technology manufacturing sector where the “economies of scale” argument has been used to build ever more so-called efficient process lines is a major challenge. The energy efficiency of the casting process has only been investigated in a limited fashion. The two “Small is Beautiful” projects aimed to introduce a new concept into foundries with regards to the use of their resources. The new philosophy, “small is beautiful”, starts by encouraging the use of high-quality feedstock, only melting what is required and only when it is required. Recycling of internal scrap is not necessarily acceptable but an aim for higher yields is. Applying counter gravity casting methods to improve yield and give enhanced quality is encouraged as is the recovery of low-grade heat from solidification. The present paper discusses the research undertaken and the key findings from the two projects.Item Open Access Energy-efficient casting processes(Springer, 2018-12-13) Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.Metal casting is one of the most energy-intensive manufacturing processes that have developed along the evolution of mankind. Although nowadays its scientific and technological aspects are well established, in the context of future resource scarcity and environmental pollution pressures, new studies appear necessary to describe the “foundry of the future” where energy and material efficiency are of great importance to guarantee competitiveness alongside environmental protection. In this chapter, both managerial and technical good practices aimed at implementing energy-efficient casting processes are presented alongside a few examples. The “Small is Beautiful” philosophy is presented as a systematic approach towards energy resilient manufacturing and, potentially, sustainability in the long term. Thus, this chapter aims at providing an overview of the different aspects comprising the state of the art in the industry and examples of research themes in academia about energy-efficient casting processes.Item Open Access Life cycle and energy assessment of automotive components manufacturing: The dilemma between aluminium and cast iron(MDPI, 2019-07-03) Salonitis, Konstantinos; Jolly, Mark R.; Pagone, Emanuele; Papanikolaou, MichailConsidering the manufacturing of automotive components, there exists a dilemma around the substitution of traditional cast iron (CI) with lighter metals. Currently, aluminum alloys, being lighter compared to traditional materials, are considered as a more environmentally friendly solution. However, the energy required for the extraction of the primary materials and manufacturing of components is usually not taken into account in this debate. In this study, an extensive literature review was performed to estimate the overall energy required for the manufacturing of an engine cylinder block using (a) cast iron and (b) aluminum alloys. Moreover, data from over 100 automotive companies, ranging from mining companies to consultancy firms, were collected in order to support the soundness of this investigation. The environmental impact of the manufacturing of engine blocks made of these materials is presented with respect to the energy burden; the “cradle-to-grave approach” was implemented to take into account the energy input of each stage of the component life cycle starting from the resource extraction and reaching to the end-of-life processing stage. Our results indicate that, although aluminum components contribute toward reduced fuel consumption during their use phase, the vehicle distance needed to be covered in order to compensate for the up-front energy consumption related to the primary material production and manufacturing phases is very high. Thus, the substitution of traditional materials with lightweight ones in the automotive industry should be very thoughtfully evaluatedItem Open Access Life cycle assessment of graphene as heating element(Springer, 2019-12-31) Ampah, Araba Darkoa; Pagone, Emanuele; Salonitis, KonstantinosAmong the various applications of graphene is the heating purpose due to its promising thermal conductivity. This paper presents a life cycle model of graphene, capturing the “cradle to gate” approach, focusing on energy consumption and environmental impact of gra-phene. The embodied energy consumption was calculated based on em-pirical data in scientific papers, patents and databases while life cycle assessment modelling software was utilised for analysing its environ-mental impact. The result from the analysis shows that, the embodied energy for the synthesis of 1 kg of graphene ranges between 264-304 MJ. Further analysis shows that, 42% of graphene embodied energy is consumed from powder preparation through to graphitization process. Moreover, the result obtained from the modelling shows dust particles and CO2 emissions into air during graphene production. This paper should be followed by further study on graphene use and end of life phases to establish a comparison with the traditional heating materials.
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