Generation Of Engines Research Articles

Thermodynamic responses of bleed air on separated flow high by-pass turbofan engine under constant speed and constant thrust cases

Gas turbine engines, especially turbofan, have been famous for their fuel economy and reliability attributes. Therefore, these have continued to be manufactured by updating their features. Therefore, thermodynamic analyses related to turbofan engines have drawn great attention, providing deeper insight into potential improvements. New generation aircrafts have been conceived to draw bleed air as little as possible from their aero-engines so as to provide lower fuel consumption. In this study, influences of bleed air ratio (BAR) ranging from 1 % to 6 % on high by-pass turbofan (HBT) engine are handled by considering constant speed (CS) and constant thrust (CT) cases. Specific fuel consumption of HBT engine changes between 20.68 g/kN and 22.25 g/kN at CT whereas varies between 20.63 g/kN and 21.9 g/kN at CS owing to variation of BAR. Moreover, exergy efficiency of HBT resides between 26.92 % and 25.02 % at CT while changes 26.99 % and 25.43 % at CS. It shows that to maintain thrust constant could slightly penalty the engine performance in terms of fuel efficiency. On the other hand, the higher BAR leads to lower exergy efficiency of the combustor, which changes 80.95 %–82.33 % ranges at CT and varies 80.77 %–82.31 % intervals at CS. Finally, improvement potential rate for the combustor is found higher 1 MW and increases with elevated BAR whereas that for other five components is measured less than 0.04 MW. It could be underscored that adverse effect of BAR for both cases is observed. It is thought that this study helps in observing what extent the engine is affected from usage of bleed air in terms of thermodynamic metrics.

Waste heat recovery from the biomass engine for effective power generation using a new array-based system

Thermoelectric generator (TEG)-thermosyphon-based heat recovery system (HRS) for harvesting the heat from the high temperature sources is a well-known technology for power generation. However, various thermal resistances (a total of nine) are involved in the thermosyphon-based HRS between the heat sources and TEGs which generate irreversibility that ultimately reduces its performance. In this work, a new design of HRS i.e. TEG-array-based is proposed for effective power generation even at low temperatures of sustainable heat source by minimizing the thermal resistances. This TEG-array-based HRS is driven by a salt gradient thermal storage device (SGTSD) which is used for efficiently recovering and storing of sustainable waste heat generated from a biomass(renewable energy)-based engine-generator. The proposed system is experimentally studied to analyse the temperature variations in SGTSD, characteristics of sustainable waste heat temperature, and performance features of TEGs in terms of obtained electrical parameters, output power and conversion efficiency. The experimental results showed that the maximum open circuit voltage, output power and conversion efficiency of TEG are obtained as 81.62V, 7.438W and 4.63\\% respectively. With this proposed system, seven thermal resistances (out of total nine) are totally eliminated while the others two are lowered that leads to effectively transfer the energy from sustainable heat source to TEGs via minor equivalent thermal resistance of 0.01198oC/W. The proposed system is found to be capable of charging a 12 V, 80 Ah heavy-duty battery for real life applications.

Deep generative design of RNA family sequences.

RNA engineering has immense potential to drive innovation in biotechnology and medicine. Despite its importance, a versatile platform for the automated design of functional RNA is still lacking. Here, we propose RNA family sequence generator (RfamGen), a deep generative model that designs RNA family sequences in a data-efficient manner by explicitly incorporating alignment and consensus secondary structure information. RfamGen can generate novel and functional RNA family sequences by sampling points from a semantically rich and continuous representation. We have experimentally demonstrated the versatility of RfamGen using diverse RNA families. Furthermore, we confirmed the high success rate of RfamGen in designing functional ribozymes through a quantitative massively parallel assay. Notably, RfamGen successfully generates artificial sequences with higher activity than natural sequences. Overall, RfamGen significantly improves our ability to design functional RNA and opens up new potential for generative RNA engineering in synthetic biology.

Reacting Flow Prediction of the Low-Swirl Lifted Flame in an Aeronautical Combustor With Angular Air Supply

Abstract The development of lean-burn combustion systems is of paramount importance for reducing the pollutant emissions of future aero engine generations. By tilting the burners of an annular combustor in circumferential direction relative to the rotational axis of the engine, the potential of increased combustion stability is opened up due to an enhanced exhaust gas recirculation between adjacent flames. The innovative gas turbine combustor concept, called the short helical combustor (SHC), allows the main reaction zone to be operated at low equivalence ratios. To exploit the higher stability of the fuel-lean combustion, a low-swirl lifted flame is implemented in the staggered SHC burner arrangement. The objective is to reach ultralow NOx emissions by complete evaporation and extensive premixing of fuel and air upstream of the lean reaction zone. In this work, a modeling approach is developed to investigate the characteristics of the lifted flame in an enclosed single-burner configuration, using the gaseous fuel methane. It is demonstrated that by using the large eddy simulation method, the shape and liftoff height of the flame are adequately reproduced by means of the finite-rate chemistry approach. For the numerical prediction of the lean lifted flame in the SHC arrangement, the focus is on the interaction of adjacent burners. It is shown that the swirling jet flow is deflected toward the sidewall of the staggered combustor dome, which is attributed to the asymmetrical confinement. Since the stabilization mechanism of the low-swirl flame relies on outer recirculation zones, the upstream transport of hot combustion products back to the flame base is studied by the variation of the combustor confinement ratio. It turns out that increasing the combustor size amplifies the exhaust gas recirculation along the sidewall, and increases the temperature of recirculating burned gases. This study emphasizes the capability of the proposed lean-burn combustor concept for future aero engine applications.

Molecular Gas-Phase Conformational Ensembles.

Accurately determining the global minima of a molecular structure is important in diverse scientific fields, including drug design, materials science, and chemical synthesis. Conformational search engines serve as valuable tools for exploring the extensive conformational space of molecules and for identifying energetically favorable conformations. In this study, we present a comparison of Auto3D, CREST, Balloon, and ETKDG (from RDKit), which are freely available conformational search engines, to evaluate their effectiveness in locating global minima. These engines employ distinct methodologies, including machine learning (ML) potential-based, semiempirical, and force field-based approaches. To validate these methods, we propose the use of collisional cross-section (CCS) values obtained from ion mobility-mass spectrometry studies. We hypothesize that experimental gas-phase CCS values can provide experimental evidence that we likely have the global minimum for a given molecule. To facilitate this effort, we used our gas-phase conformation library (GPCL) which currently consists of the full ensembles of 20 small molecules and can be used by the community to validate any conformational search engine. Further members of the GPCL can be readily created for any molecule of interest using our standard workflow used to compute CCS values, expanding the ability of the GPCL in validation exercises. These innovative validation techniques enhance our understanding of the conformational landscape and provide valuable insights into the performance of conformational generation engines. Our findings shed light on the strengths and limitations of each search engine, enabling informed decisions for their utilization in various scientific fields, where accurate molecular structure determination is crucial for understanding biological activity and designing targeted interventions. By facilitating the identification of reliable conformations, this study significantly contributes to enhancing the efficiency and accuracy of molecular structure determination, with particular focus on metabolite structure elucidation. The findings of this research also provide valuable insights for developing effective workflows for predicting the structures of unknown compounds with high precision.

Motivation and the role of empathy in engineering work

ABSTRACT Societal perceptions of engineering as a discipline now depict engineering as a profession that enables social, economic, and environmental problems to be addressed on a global scale. This expanded view of engineering has had myriad impacts on priorities for engineering education and practice. One such impact has been to foreground discussions about the role that empathy may play in engineering practice. This manuscript discusses the evolution of the concept of empathy in the engineering field, and the relevance of empathy to various generic engineering attributes, including leadership, problem-solving, and design thinking. The manuscript then discusses the idea that motivation plays a central role in improving and increasing empathy in engineering work.

Development and investigation of a hydrogen enriched natural gas fuelled HCCI engine for combined generation of power, heating, and cooling

Development and investigation of a hydrogen enriched natural gas fuelled HCCI engine for combined generation of power, heating, and cooling

APPLICATIONS AND ANALYSIS METHODS OF TURBULENT COMBUSTION: A REVIEW

Currently, about 80% of the world's energy is generated through the combustion of various fuel types. As this trend is anticipated to persist for the next several decades, combustion technology is poised to retain its pivotal role in energy production. Industries such as power generation, automobile manufacturing, and aerospace engineering invariably rely on combustion engineering applications, all of which frequently involve turbulent flows. Therefore, a comprehensive understanding of the intricate interplay between turbulence and combustion, along with the underlying structure and dynamics of flames, becomes imperative for facilitating optimal design and advancement of these applications. This article undertakes a review of the noteworthy contributions made in recent decades, along with the diverse applications of turbulent combustion across various industries. It provides an overview of computational simulation approaches and experimental methodologies employed in this field. Furthermore, it delves into the current state of knowledge, assessing the capabilities and limitations of present techniques. The article also outlines several ongoing challenges in modeling, indicating pathways for future research endeavors.

A Sustainability-Driven Comparison of Methods for the Identification of Lightweight Design Potentials in Product Generation Engineering

Today's product development is challenged with redesigning products into more sustainable variants while maintaining economic and technical feasibility. Among the ways to address this, lightweight design offers numerous opportunities to increase the product's resource efficiency while reducing emissions and emerging life cycle costs. However, this requires advanced analysis concepts to be applied in the early phase of development to efficiently allocate engineering capacities and to subsequently exploit environmental sustainability potentials in the best possible way. Therefore, the present work contrasts two lightweight design methods: the ‘extended target weighing approach’ (ETWA) and the ‘functional life cycle energy analysis’ (FLCEA). Based on the use case of the generation development of a semi-mobile handling system, their respective strengths, and weaknesses for a sustainable life cycle engineering are highlighted. While the widely known ETWA focuses on three coupled impact categories (mass, costs, and CO2 emissions), the novel FLCEA method only addresses the mass-related energy consumptions, albeit more detailed across three life cycle stages. As a result of it, the application effort can be decreased, while on the one hand the meaningfulness for the environmental sustainability effects of design changes remains unaltered and, on the other hand, the derivation of recommendations for action is facilitated.

Utilizing Generative Design Algorithms for Innovative Structural Engineering Solutions

The present research paper examines the application of generative design algorithms in the area of structural engineering. This new approach has transformed the field of structural engineering through its innovative solutions. The integration of algorithms and AI in generative engineering enables the investigation of broad possibilities for design, with a goal of increasing the productivity, environmental sustainability and aesthetically appeal of constructions. The current research examines the effective implementation of generative design algorithms for dealing with difficult structural issues to generate creative solutions. The text explores into the mathematical methods included its effect on sustainable design, and the potential for customization throughout the area of structural engineering. This study also explores case studies in which the use of generative design is being successfully implemented, providing valuable insights into its real-world benefits and limitations. The main objective is to prove the consequences of generative design algorithms for the design procedure, as well as their involvement in increased creativity, efficiency, as well as environmental sustainability in the field of construction engineering.

ChatGPT Search as a tool for scholarly tasks: evolution or devolution?

ChatGPT Search was launched on October 31 by OpenAI as a new AI-powered search engine. Among its features, it stands out for its ability to retrieve information from various online sources, including scholarly databases, which potentially allows the use of this tool for academic tasks, both quantitative and qualitative. To test its features, five academic tasks are designed: two quantitative (collecting hit count estimates from Google Search and scraping bibliometric indicators from ResearchGate); two qualitative tasks (performing a narrative synthesis of an academic topic and generating a brief academic author profile), and a mixed task (identifying, collecting and describing a list of publications from Google Scholar Profiles). The results show the inability of ChatGPT Search to conduct quantitative tasks correctly, fabricating the results (hallucination). Qualitative tasks are performed with better results; however, errors are detected, which prevent recommending the tool without manual analysis and refinement. Finally, the ability to generate links to scientific publications can open up competition among academic sites to be mentioned in the ChatGPT Search responses, giving rise to Academic Generative Engine Optimization (A-GEO).

The thermal and stored heat energy driving a Stirling engine for power generation

South Africa’s national power grid is currently in dire straits. The lack of a dependable power supplier and rising electricity costs force the public and businesses to look for alternatives to meet their energy needs. These alternatives are costly to implement and beyond the financial reach of most South Africans. The most common alternative energy source is solar photovoltaic systems with large battery banks to survive Eskom's long, regular load-shedding schedules. This research aims to design and simulate a combined solar-thermal and stored heat energy-powered Stirling engine for power generation. The output of the research simulation was compared to a standard photovoltaic installation of similar power output. The results for this paper were generated from the simulation software package MATLAB. Such a system must have a lower capital cost to compete with solar photovoltaic systems with battery backup. The Stirling system was found to be cheaper than the deep-cycle gel system and about 11% cheaper than the PV system using lithium iron phosphate.

Guide to Education and Employment Matching Supply and Demand Project by Ministry of Education and GMT Technology (SHENZHEN) Co.,Ltd.

Under the guidance of the Ministry of Education, GMT Technology (Shenzhen) Co., Ltd. has carried out Education and Employment Matching Supply and Demand Project, including three major categories: targeted talent cultivation and training projects, employment internship base projects, and human resource improvement projects, totaling 35 projects, involving economics and trade, art and design, computer science and technology, bioengineering, food science and engineering, new energy power generation engineering, aerospace, and transportation Majors such as art studies.

From Human Labor to Electric Vehicles: The Evolution of Engines

Engines have come a long way since humans first used their own labour and muscle power to perform mechanical work. This research paper traces the remarkable journey of engine evolution, highlighting key milestones in the transition from human and animal labour to waterwheels, windmills, internal combustion engines, and ultimately, electric vehicles (EVs). The paper examines the drawbacks of each engine type, from the limitations of human and animal power to the geographical constraints of waterwheels and windmills. It then delves into the invention of the steam engine, a pivotal moment in the Industrial Revolution, which freed machines from the need for proximity to water or wind sources. The paper provides a detailed explanation of how steam engines work, emphasizing their historical significance and continued relevance, particularly in electricity generation and even nuclear submarines. However, it also acknowledges the limitations and safety concerns associated with steam engines. Transitioning to the present, the paper introduces the concept of internal combustion engines, both gasoline and diesel-powered, highlighting their efficiency and the pros and cons of each type. The importance of fuel efficiency is emphasized, as fossil fuels are finite resources. The paper concludes by examining the latest generation of engines – electric motors, particularly in EVs. It discusses the various types of batteries used in EVs, such as Lithium-ion, Nickel-Metal Hydride, and Lead-Acid batteries, highlighting their characteristics and environmental impact. In summary, this research paper provides a comprehensive overview of the evolution of engines over time, from the simplest human-powered machinesto the cutting-edge technology of electric vehicles. It underscores the importance of technological advancements in addressing energy efficiency and environmental sustainability in the automotive industry. This research paper will explore the following key questions: ● What are the key milestones in the evolution of engines? ● What are the challenges and opportunities associated with the transition to electric mobility? ● What are the implications of this shift for the future of transportation?

High-Temperature Oxidation and Microstructural Changes of Al0.75CoCrFeNi High-Entropy Alloy at 900 and 1100 °C

The development of high-entropy alloys (HEAs) for high-temperature applications has been driven by the limitation of nickel-based superalloys in achieving optimal efficiency at higher temperatures for higher efficiency in power generation engines. The alloys must have high oxidation resistance and microstructural stability at high temperatures. Relatively equimolar multi elements involved in HEAs produce microstructure containing a single solid solution or multiphase that improves the mechanical properties and oxidation resistance resulting from sluggish diffusion and core effects. In this study, the oxidation behavior and microstructural changes of Al0.75CoCrFeNi HEA at 900, 1000, and 1100 °C in air atmosphere were investigated. Based on the XRD and SEM-EDS analysis, the mechanism of oxide scale formation and microstructural changes of the substrate are proposed. The results show that the oxidation behavior of the alloy follows a logarithmic rate law. Different oxide compounds of CoO, NiO, Cr2O3, and CrO3, θ-Al2O3, α-Al2O3, and Ni(Cr,Al)2O4 with semicontinuous oxides of Al2O3 with Cr2O3 subscale and an oxide mixture consisting of spinel of Ni(Cr,Al)2O4 and Co(Cr,Al)2O4 were found. During oxidation, Widmanstätten of FCC-A1 and BCC-B2/A2 phases in the substrate have changed. Spheroidization of B2 and a reduction in volume fraction decrease the hardness of the substrates.

Characteristics of ocean current meandering and potential efficacy of maximizing power capacity by tracking short-term meanders with hydro sail enabled active mooring

This research studies the characteristics of ocean current meanders from the viewpoint of power generation engineering and the potential of maximizing ocean current power generation capacity by making generator turbines to track the meanders applying a recently proposed Cross-stream Active Mooring concept. The current meanders will hurt capacity factor of marine turbines moored at fixed locations, somewhat like the issue of wind availability for wind farms. The new mooring concept features a hydro sail system that can deploy generator turbines transversely across streams in a marine current. The hydro sail system can further adjust the horizontal position of the turbines, by changing sail angle of attack, to actively track fast streams in an ocean current. This paper first reviews and discusses the characteristics of short-term track variations of the Florida Current and the Kuroshio near Taiwan and then analyzes potential improvement in power generation using measured and simulated current velocity data in the two ocean currents, suggesting a potential increase of 10–40 % power generation achievable by tracking the meanders. Operations of the hydro sail were demonstrated by tests using remote controllable and passive scale models. Control methods are discussed. Approaches to observe, predict and track the meanders are conceptualized.

Investigation of the basic parameters for alternative solid rocket propellant engines for research and civilian use

Investigation of the basic parameters for new generation of alternative solid rocket propellant engines for research and civilian use was implemented. This was caused from needs for substitution of the widely used construction materials of the aircraft units based on polymers and of petroleum composites. Numerous fire tests, both static and flight, in a real working environment of a new generation of environmentally friendly solid rocket propellant engines that are completely degradable in the nature were carried out. The obtained results after burning of rocket fuel for internal engine ballistics and thermo-mechanical coupled characteristics of composite materials are presented.

Efficient Spatially Sparse Inference for Conditional GANs and Diffusion Models.

During image editing, existing deep generative models tend to re-synthesize the entire output from scratch, including the unedited regions. This leads to a significant waste of computation, especially for minor editing operations. In this work, we present Spatially Sparse Inference (SSI), a general-purpose technique that selectively performs computation for edited regions and accelerates various generative models, including both conditional GANs and diffusion models. Our key observation is that users prone to gradually edit the input image. This motivates us to cache and reuse the feature maps of the original image. Given an edited image, we sparsely apply the convolutional filters to the edited regions while reusing the cached features for the unedited areas. Based on our algorithm, we further propose Sparse Incremental Generative Engine (SIGE) to convert the computation reduction to latency reduction on off-the-shelf hardware. With about 1%-area edits, SIGE accelerates DDPM by 3.0× on NVIDIA RTX 3090 and 4.6× on Apple M1 Pro GPU, Stable Diffusion by 7.2× on 3090, and GauGAN by 5.6× on 3090 and 5.2× on M1 Pro GPU. layers and apply it to Stable Diffusion. Additionally, we offer support for Apple M1 Pro GPU and include more results to substantiate the efficacy of our method.

Noise Prediction of an Open Fan Using Acoustic Analogy Approaches

The purpose of this study is to evaluate numerical aero-acoustic methods for the noise prediction of an open fan, which is expected to reduce CO2 emissions for the next generation of aircraft engines. The far-field noise is computed using a CFD/CAA approach. The unsteady Reynolds Averaged Navier-Stokes (uRANS) and the Ffowcs Williams-Hawkings (FWH) analogy using solid and permeable surfaces are applied. The phase-lag method (single-blade passage) is used for the purpose of calculation for aerodynamic flow and noise sources with ONERA elsA finite volume solver. The sensitivities to the numerical CFD setup as well as the position and formulation of FWH permeable surface for noise computation are discussed in this paper. The present noise prediction strategy is evaluated for approach and take-off operating conditions. In particular, several spatial discretization schemes and FWH surface locations are tested and compared to evaluate their influence on the noise levels and directivity.

CRAFTing Delivery of Membrane Proteins into Protocells using Nanodiscs.

For the successful generative engineering of functional artificial cells, a convenient and controllable means of delivering membrane proteins into membrane lipid bilayers is necessary. Here we report a delivery system that achieves this by employing membrane protein-carrying nanodiscs and the calcium-dependent fusion of phosphatidylserine lipid membranes. We show that lipid nanodiscs can fuse a transported lipid bilayer with the lipid bilayers of small unilamellar vesicles (SUVs) or giant unilamellar vesicles (GUVs) while avoiding recipient vesicles aggregation. This is triggered by a simple, transient increase in calcium concentration, which results in efficient and rapid fusion in a one-pot reaction. Furthermore, nanodiscs can be loaded with membrane proteins that can be delivered into target SUV or GUV membranes in a detergent-independent fashion while retaining their functionality. Nanodiscs have a proven ability to carry a wide range of membrane proteins, control their oligomeric state, and are highly adaptable. Given this, our approach may be the basis for the development of useful tools that will allow bespoke delivery of membrane proteins to protocells, equipping them with the cell-like ability to exchange material across outer/subcellular membranes.