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Toward net zero: an engine electrification strategy approach of fuel cell and steam injection
Get PDFThe turbofan engine electrification is a promising element in the global effort to achieve the 2050 net-zero emission target. This transformative shift embraces alternative energy sources and amplifies system efficiency. Power injection, using the electric motor to provide power assistance for the gas turbine, is a promising concept. Batteries and fuel cells are emerging as prime candidates for replacing traditional fossil fuel power requirements, offering compelling advantages, particularly with electric powertrains offering superior efficiency compared to conventional gas turbines. This direct power injection assistance reduces the power requirement from the combustion, thus reducing the fuel flow and Turbine Entry Temperature (TET). As an outcome, this alteration yields favourable consequences, notably in the form of diminished Carbon Dioxide (CO2) and Nitrogen Oxide (NOx) emissions and lower engine fuel consumption. However, this transition comes at the cost of a potential thermal efficiency penalty, impacts engine stability, and adds extra weight. These drawbacks compromise the power injection’s benefit, highlighting the necessity for introducing electrification strategies in future engine designs.
This paper presents an innovative electrification strategy using fuel cells as the power source for engine electrification. The strategy highlights the collection of water as a by-product, followed by treatment processes involving condensation, pressurisation, and superheating. In this configuration, the fuel cell is designed to provide power to the electric motor, which injects power into the low-pressure shaft of the engine and provides assistance. Additionally, steam injection, leveraging the by-product water, enhances the benefits derived from electrification by recovering and redirecting the waste heat from exhaust gases into the combustor.
To evaluate the potential impact of this electrification strategy, this research selected and modelled three representative engines, each representative of typical thermodynamic cycles. Two different approaches to steam management were considered, including instantaneous injection with production and storage of steam during production for release during specific flight segments.
This research established the synergy between steam injection and different engine thermodynamic cycles, providing a visualised evaluation method. The impact of fuel cell electrification on fuel consumption has been quantified. An estimation of the weight penalty, including fuel cells, hydrogen storage and heat exchanger, is also provided. Furthermore, the sizing of the superheating heat exchanger is analysed to assess its influence on the electrification strategy.
This research discovered the impact of steam injection on different engine cycles, established the benefits and constraints, and explained the physics. This research has captured the physics of recovering the waste heat from exhaust pipes, which could compromise fuel consumption benefit and impose a penalty on electrification. This research also indicated under what conditions and phases it is better to use the fuel cell with steam injection.
The results and assessments reach the conclusion that the electrification strategy of fuel cell and steam injection is preferable for high-temperature, low-specific thrust engines. An improper deployment could lead to a penalty instead of a benefit. The temperature of the steam is the dominant factor in bringing fuel consumption benefits. Thus, the preferable steam management approach is to inject during T/O and climb.ASME Turbo Expo 2024: Turbomachinery Technical Conference and Expositio
Integrating digital twin technologies into the group design project for the Advanced Air Mobility Systems MSc course
Get PDFThis study aims to develop the content and material for the Group Design Project (GDP) with Digital Twin (DT) technologies, aligned with Future Flight Challenge (FFC) project deliveries involving Cranfield, the emerging Research and Development (R&D) capacities, and the increasing demands for talent and workforce from the industry. The GDP delivery and learning approach, structured as a five-phase process - project and technical management, Concept of Operations (ConOps) and requirements definition, system development, case study and evaluation, and final results - is stated in the paper. This proposed approach has been evaluated with the AAMS 23/24 academic year MSc GDP.2nd IFAC Workshop on Aerospace Control Education - WACE 2024IFAC-PapersOnLin
Negative social tipping dynamics resulting from and reinforcing Earth system destabilization
Get PDFIn recent years, research on normatively positive social tipping dynamics in response to the climate crisis has produced invaluable insights. In contrast, relatively little attention has been given to the potentially negative social tipping processes that might unfold due to an increasingly destabilized Earth system and to how they might in turn reinforce social and ecological destabilization dynamics and/or impede positive social change. In this paper, we discuss selected potential negative social tipping processes (anomie, radicalization and polarization, displacement, conflict, and financial destabilization) linked to Earth system destabilization. We draw on related research to understand the drivers and likelihood of these negative tipping dynamics, their potential effects on human societies and the Earth system, and the potential for cascading interactions (e.g. food insecurity and displacement) contributing to systemic risks. This first attempt to provide an explorative conceptualization and empirical account of potential negative social tipping dynamics linked to Earth system destabilization is intended to motivate further research into an under-studied area that is nonetheless crucial for our ability to respond to the climate crisis and for ensuring that positive social tipping dynamics are not averted by negative ones.UK Research and Innovation, Science and Technology Facilities Council, European Commission, Deutsche Forschungsgemeinschaft, European Research Council, Engineering and Physical Sciences Research Council, Natural Environment Research CouncilThis research has been supported by the UK Research and Innovation (grant no. MR/V021141/1).Earth System Dynamic
Microbial electrochemical enhanced composting of sludge and kitchen waste: electricity generation, composting efficiency and health risk assessment for land use
Get PDFTo realize the energy and resource utilization from organic solid waste, a two-phase microbial desalination cell (TPMDC) was constructed using dewatered sludge and kitchen waste as the anode substrate. The performance of electricity generation and composting efficacy was investigated, along with a comprehensive assessment of the potential health risks associated with the land use of the resulting mixed compost products. Experimental outcomes revealed a maximum open-circuit voltage of 0.893 ± 0.005 V and a maximum volumetric power density of 0.797 ± 0.009 W/m³. After 90 days of composting enhanced by microbial electrochemistry, a significant organic matter removal rate of 31.13 ± 0.44 % was obtained, and the anode substrate electric conductivity was reduced by 30.02 ± 0.04 % based on the anode desalination. Simultaneously, there was an increase in the content of available nitrogen, phosphorus, and potassium, as well as an improvement in the seed germination index. The forms of heavy metals shifted from bioavailable to stable residual states. The non-carcinogenic hazard index (HI) values for heavy metals and polycyclic aromatic hydrocarbons (PAHs) during the land use of compost products were less than 1, and the total carcinogenic risk (TCR) values for heavy metals and PAHs were below the acceptable threshold of 10−4. The occupational population risk of infection from five pathogens was higher than that of the general public, with all risk values ranging from 8.67 × 10−8 to 1, where the highest risk was attributed to occupational exposure to Legionella. These outcomes demonstrated that the mixture of dewatered sludge and kitchen waste was an appropriate anode substrate to enhance TPMDC stability for electricity generation, and its compost products have promising land use suitability and acceptable land use risk, which will provide important guidance for the safe treatment and disposal of organic solid waste.The authors gratefully acknowledge funding from Project 52270122 and 51608155 supported by National Nature Science Foundation of China, Project LH2021E097 supported by the Natural Science Foundation of Heilongjiang Province, Project QMPT-2007 supported by Harbin Medical University, support of China Scholarship Council.Heliyo
Diversity and bioactivity of endophytic actinobacteria associated with the roots of artemisia herba-alba asso from Algeria
Get PDFThe datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request, while 16S rRNA data generated are available in the Genbank repository.The isolation of endophytic actinobacteria from the roots of wild populations of Artemisia herba-alba Asso, a medicinal plant collected from the arid lands of Algeria, is reported for the first time. Forty-five actinobacterial isolates were identified by molecular analysis and in vitro evaluated for antimicrobial activity and plant growth-promoting (PGP) abilities (1-Aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, nitrogen fixation, phosphate and potassium solubilization, ammonia, and siderophores production). The phylogenetic relationships based on 16S rRNA gene sequences show that the genus Nocardioides (n = 23) was dominant in the sampled localities. The remaining actinobacterial isolates were identified as Promicromonospora (n = 11), Streptomyces (n = 6), Micromonopora (n = 3), and Saccharothrix (n = 2). Only six (13.33%) strains (five Streptomyces and one Saccharothrix species) were antagonistic in vitro against at least one or more indicator microorganisms. The antimicrobial activity of actinobacterial strains targeted mainly Gram-positive bacteria. The results demonstrate that more than 73% of the isolated strains had ACC deaminase activity, could fix atmospheric nitrogen and were producers of ammonia and siderophores. However, only one (2.22%) strain named Saccharothrix sp. BT79 could solubilize phosphorus and potassium. Overall, many strains exhibited a broad spectrum of PGP abilities. Thus, A. herba-alba provides a source of endophytic actinobacteria that should be explored for their potential biological activities.Ministry of Higher Education and Scientific ResearchCurrent Microbiolog
A framework for enabling metaverse for sustainable manufacturing
Get PDFNewly introduced technologies often require time for adoption and integration into manufacturing environments, for several reasons including technological maturity, adoption costs, and skills gaps. The inclusion of sustainability as a new requirement for both customers and producers adds further complexity to the equation. As metaverse technology became available, it became logical to establish a set of requirements to harness its new potential and create a sustainability-oriented framework for seamless integration into modern smart manufacturing environments. Against this background, the current work introduces a framework aimed at harnessing the potential of the metaverse to enhance manufacturing sustainability. As a case study, an industrial workshop was analysed and evaluated using the proposed framework. The findings help create a future plan for leveraging the use of the metaverse and prioritising its requirements.34th CIRP Design Conference 2024Procedia CIR
Design of nonlinear gradient sheet-based TPMS-lattice using artificial neural networks
Get PDFGradient triply periodic minimal surface (TPMS) structures are renowned for lightweight design and enhanced performance, but their complex and nonlinear configurations pose challenges in achieving targeted design goals. A new design methodology for the nonlinear gradient structure was proposed in this study, with the aim of achieving efficient and accurate modeling of complex and gradient sheet-based TPMS structures under specific performance objectives. This method utilized automated finite element (FE) simulations to obtain structure topology element densities under various boundary conditions. An artificial neural network (ANN) was then employed to efficiently predict the correspondence between these boundary conditions and topology element densities. A mapping was established between topology element densities and TPMS structural parameters, and the gradient structure was accurately constructed by using the voxel modeling technique. Taking a typical cantilever beam TPMS structure as an example of nonlinear gradient design, the results indicate that the error between the ANN-predicted and FE-simulated structure topology element densities is only 2.73 %, with prediction time being only 0.15 % of the simulation time. The thin regions of the gradient structure align with those geometrically removed in regular topology optimization scheme, achieving up to 65.45 % weight reduction, a 28.72 % improvement over the regular scheme, along with uniform structural stress transition and maximum stress reduction. TC4 alloy nonlinear gradient TPMS structures, printed by metal selective laser melting (SLM) technique, confirm the practical application value of this design method.National Natural Science Foundation of ChinaThe authors wish to gratefully acknowledge the financial support from the National Natural Science Foundation of China (Grant No. 52105418), the Natural Science Foundation of Hunan Province (Grant No. 2023JJ20069, 2023JJ40752 and 2022JJ40600), and the key scientific research project of Hunan Provincial Department of Education (Grant No. 23A0001).Journal of Materials Research and Technolog
Automatic defect detection in infrared thermal images of ancient polyptychs based on numerical simulation and a new efficient channel attention mechanism aided Faster R-CNN model
Get PDFIn recent years, the preservation and conservation of ancient cultural heritage necessitate the advancement of sophisticated non-destructive testing methodologies to minimize potential damage to artworks. Therefore, this study aims to develop an advanced method for detecting defects in ancient polyptychs using infrared thermography. The test subjects are two polyptych samples replicating a 14th-century artwork by Pietro Lorenzetti (1280/85–1348) with varied pigments and artificially induced defects. To address these challenges, an automatic defect detection model is proposed, integrating numerical simulation and image processing within the Faster R-CNN architecture, utilizing VGG16 as the backbone network for feature extraction. Meanwhile, the model innovatively incorporates the efficient channel attention mechanism after the feature extraction stage, which significantly improves the feature characterization performance of the model in identifying small defects in ancient polyptychs. During training, numerical simulation is utilized to augment the infrared thermal image dataset, ensuring the accuracy of subsequent experimental sample testing. Empirical results demonstrate a substantial improvement in detection performance, compared with the original Faster R-CNN model, with the average precision at the intersection over union = 0.5 increasing to 87.3% and the average precision for small objects improving to 54.8%. These results highlight the practicality and effectiveness of the model, marking a significant progress in defect detection capability, providing a strong technical guarantee for the continuous conservation of cultural heritage, and offering directions for future studies.Ministry of Education, Universities and Research, Ministry of Science and Technology of the People's Republic of ChinaThis work is supported by the Ministry of Science and Technology of China (MOST) through the National Key R&D Program (Grant No. 2023YFE0197800). This work is also supported by the Ministry of University and Research of Italy (Grant No. PGR02016).Heritage Scienc
Nonlinear behaviour in flexible, large-scale space structures: dynamics and control
No full textLarge-scale structures are becoming increasingly common for space applications, driven by advances in in-orbit manufacturing and construction, lightweight materials, and robotics. While these structures have the potential to be key enablers for the next generation of space applications—see, for example, recent interest in space-based solar power—their ability to deliver such goals depends on the stability and controllability of their dynamics. Large-scale space structures, which often have architectures at the kilometre length scale, face several important dynamic challenges. In this work, we propose a novel control strategy for flexible satellites based on a dual unscented Kalman filter strategy. The methodology is outlined and then applied to a smaller satellite, which is assumed to be linear. A key aim of this research is the accurate identification of the moment of inertia of the system, which we demonstrate the methodology can achieve within 1% (or significantly closer), even when the initial assumptions are inaccurate. Finally, we discuss the implications for larger structures, and how the work will be expanded in the future.42nd IMAC, A Conference and Exposition on Structural Dynamics, 2024Nonlinear Structures & Systems, Vol.
UAVs as a tool for optimizing boat-supported flood evacuation operations
Get PDFThe frequency and intensity of flood events are increasing year by year as a result of climate change. This poses significant threats to human settlements and adversely affects biodiversity, agriculture, and infrastructure. One of the most prominent and traditional flood evacuation approaches is through the use of boats. Nonetheless, serious challenges exist with respect to determining the optimal deployment locations, routes, and timing. Given research advances in the Unmanned Aerial Vehicles (UAVs) sector—and their ability to offer real-time data and aerial monitoring services—we argue that their applications could help enhance boat-supported flood evacuation operations. In this opinion piece, we explore new opportunities for disaster management and underscore the advantages of integrating UAVs into flood evacuation methodologies, including areas of rapid field assessment, optimal route planning, and improved coordination between rescue boats. Notwithstanding the potential of UAVs, we emphasize several gaps to be explored in terms of large-scale data management/processing, regulatory limitations, and technological know-how. Furthermore, we provide recommendations for bolstering boat deployment protocols, disaster preparedness training programs, policy frameworks, and emergency response systems, which could maximize their efficacy in flood evacuation scenarios.Drone