Generation Of Engines Research Articles

Triangle nanowall arrays of ultrathin MoS2 nanosheets vertically grown on Co-Fe bimetallic disulfide as highly efficient electrocatalysts for hydrogen evolution reaction

Hydrogen evolution reaction (HER) in water splitting normally requires efficient and durable electrocatalysts. Herein, we demonstrate Fe-CoS2@MoS2 triangle nanowall arrays grown on carbon cloth (CC) exhibiting superior electrocatalytic performance for HER. In this strategy, CC acts as conductive substrate to generate Co-MOF and Fe is introduced through ligand exchange of [Fe(CN)6]4−, and sulfidation treatment produces the Co-Fe bimetallic disulfide (noted as Fe-CoS2) nanowall arrays, on which vertically oriented MoS2 nanosheets grow via hydrothermal reaction. The as-obtained CC@Fe-CoS2@MoS2 catalyst shows an extremely low overpotential of 68 mV to deliver 10 mA cm−2 current density (η10 = 68 mV) and high stability (24 h) in acid media (0.5 M H2SO4). The vertically growing MoS2 ultrathin nanosheets expose more catalytic active sites. Meanwhile, electron transfer from Co to Mo may result in increased electron density of MoS2 thus enhancing the conductivity. The DFT calculations reveal that the hybridization of MoS2 and Fe-CoS2 dramatically reduces the Gibbs free energy of H adsorption and speeds up HER process. All the above merits contribute to the improved HER performance. This study will provide an inspiration for the design of novel electrocatalysts via interface engineering for scalable hydrogen generation.

Implementations of new generation engineering ethics in education and industry for social happiness: A macroscopic overview from Turkey to World

Implementations of new generation engineering ethics in education and industry for social happiness: A macroscopic overview from Turkey to World

Virtual reality for synergistic surgical training and data generation

ABSTRACT Surgical simulators not only allow planning and training of complex procedures, but also offer the ability to generate structured data for algorithm development, which may be applied in image-guided computer assisted interventions. While there have been efforts on either developing training platforms for surgeons or data generation engines, these two features, to our knowledge, have not been offered together. We present our developments of a cost-effective and synergistic framework, named Asynchronous Multibody Framework Plus (AMBF+), which generates data for downstream algorithm development simultaneously with users practicing their surgical skills. AMBF+ offers stereoscopic display on a virtual reality (VR) device and haptic feedback for immersive surgical simulation. It can also generate diverse data such as object poses and segmentation maps. AMBF+ is designed with a flexible plugin setup that allows for unobtrusive extension for simulation of different surgical procedures. We show one use case of AMBF+ as a virtual drilling simulator for lateral skull-base surgery, where users can actively modify the patient anatomy using a virtual surgical drill. We further demonstrate how the data generated can be used for validating and training downstream computer vision algorithms.

Semantic function module pipeline generation

Abstract With modular automation, modular industrial plants use a functional engineering approach, and modules enable plug & produce plant engineering. However, plant configuration is still a largely manual process and often not optimized with respect to the available information. In this contribution, we propose a system and algorithm to support the automation engineer in the process of joining together modules into process pipelines and in their optimization. Our solution is built upon an abstract semantic data model that facilitates the automated matching of pre- and post-condition of modules and of the things that are processed by these modules. The pipeline generation engine is further extended by means of an optimization and ranking algorithm, and thus enables automated inter-module pipeline generation and plant optimization. We evaluate our system by means of a simple fictional use case scenario and prove feasibility, applicability as well as the huge potential for time and cost savings.

Path Exploration of Integrating Ideological and Political Elements into the Teaching of “Biomass Power Generation Engineering”

Curriculum ideological and political education is not only an important way for the education reform in colleges and universities, but also the internal requirement for the fundamental task of building morality and cultivating students. Biomass power generation engineering is an essential and featured professional course of new energy science and engineering major. Taking the course teaching of "biomass power generation engineering" as an example, this study analyzed the necessity of carrying out the ideological and political education, and explored the top-level design scheme of the curriculum ideological and political education and the trinity educational objectives. Meanwhile, the ways of mutual integration of ideological and political elements and professional knowledge points were discussed, and the curriculum teaching reform and practical exploration were carried out, so that the ideological and political education could run throughout the whole process of course learning. The purpose is to provide reference for the ideological and political teaching of science and engineering courses.

From Textbook to Teacher: an Adaptive Intelligent Tutoring System Based on BCI.

In this work, we propose FT3, an adaptive intelligent tutoring system based on Brain Computer Interface(BCI). It can automatically generate different difficulty levels of lecturing video with teachers from textbook adapting to student engagement measured by BCI. Most current studies employ animated images to create pedagogical agents in such adaptive learning environments. However, evidence suggests that human teacher video brings a better learning experience than animated images. We design a virtual teacher generation engine consisting of text-to-speech (TTS) and lip synthesis method, being able to generate high-quality adaptive lecturing clips of talking teachers with accurate lip sync merely based on a textbook and teacher's photo. We propose a BCI to measure engagement, serving as an indicator for adaptively generating appropriate lecturing videos. We conduct a preliminary study to build and evaluate FT3. Results verify that FT3 can generate synced lecturing videos, and provide proper levels of learning content with an accuracy of 73.33%.

(Invited) Towards Addressing Fundamental Scale-up Questions for Low-Temperature Electrolysis Electrodes

Industry and government aspirations continue to converge regarding the need for energy-system-wide solutions to environmental, sustainability, and climate challenges. Among other bold programs, the Department of Energy’s Hydrogen-at-Scale initiative seeks to exploit the most abundant element on the planet as a ubiquitous energy source, touching nearly every aspect of the energy, industrial, and transportation systems as a long-term storage medium, a feedstock, a processing agent, or a fuel. Central to the concept is the ability to generate hydrogen from water by leveraging clean and low-cost electricity from renewables. Low-temperature water electrolysis (LTE) systems are seen as the primary engine for clean hydrogen generation and are envisioned to provide a pathway to gigawatt-scale production. At present, however, volumes for LTE system are still small, and thus high-volume manufacturing of the electrochemical cell materials, as well as stack and system components, is also aspirational. The membrane electrode assembly (MEA) is where the rubber meets the road for these systems, in terms of performance and lifetime, and account (depending on production volume) for approximately half of system costs. Membranes for the LTE MEAs are commercially available, though further improvements in cost, performance, and durability are still rightly sought. Electrodes on the other hand, are at present a bit of a black box. Further development of catalysts and ion-conducting polymers notwithstanding, fundamental questions about electrode structure and fabrication remain to be answered. What is their optimal morphology (and is it the same for performance and durability)? How do the formulation, properties, and processing of the dispersed catalyst-ionomer ink impact the morphology? How do the physics and parameters of the coating and drying processes also impact the morphology? Research efforts to address these questions are complicated by multiple pathways to construct the MEA – including decal-transfer, directly coating the membrane, or directly coating the porous media – as well as a great variety of coating processes that could be used. These different factors not only potentially affect the performance of the MEA, but they affect cost. In this talk, manufacturing pathways and challenges for LTE electrodes – informed by the greater breadth and maturity of similar work for low-temperature fuel cells – will be discussed. Along the way, examples of activities at the National Renewable Energy Laboratory and partner labs to address some of these fundamental questions, via several lab consortia and industry partnerships, will be given.

Software Training in HEP

The long-term sustainability of the high-energy physics (HEP) research software ecosystem is essential to the field. With new facilities and upgrades coming online throughout the 2020s, this will only become increasingly important. Meeting the sustainability challenge requires a workforce with a combination of HEP domain knowledge and advanced software skills. The required software skills fall into three broad groups. The first is fundamental and generic software engineering (e.g., Unix, version control, C++, and continuous integration). The second is knowledge of domain-specific HEP packages and practices (e.g., the ROOT data format and analysis framework). The third is more advanced knowledge involving specialized techniques, including parallel programming, machine learning and data science tools, and techniques to maintain software projects at all scales. This paper discusses the collective software training program in HEP led by the HEP Software Foundation (HSF) and the Institute for Research and Innovation in Software in HEP (IRIS-HEP). The program equips participants with an array of software skills that serve as ingredients for the solution of HEP computing challenges. Beyond serving the community by ensuring that members are able to pursue research goals, the program serves individuals by providing intellectual capital and transferable skills important to careers in the realm of software and computing, inside or outside HEP.

COMBINED POWER PLANT OF A MOTOR VEHICLE

Currently, the most promising areas of development of motor transport are an increase of the horsepower characteristic of their power plants as well as increase of fuel efficiency, and reduction of the toxicity level of exhaust fumes. An internal combustion engine as a power unit of the car in a number of operation modes (supplemental motion, small work load, idling, etc.) works extremely inefficiently and contains the high concentration of harmful components in the exhaust fumes. Additionally, in a context of growing shortage of carbohydrate fuels and increase in their value, the problem of the fuel-burn improvement is especially acute. To improve the environmental compatibility and efficiency of power plants of the vehicles, combined cycle power plants are used. One of the most important problems that the machine construction faces is the creation of environmentally friendly and economical power plants. A hybrid power plant, which contains several power units operating on different physical principles, is proposed by the authors. The main power unit uses the energy of liquid or gaseous fuel in the mode of an internal combustion engine; the auxiliary power unit which is made as a reverse volumetrical driving machine with swinging motion of the work tools (forcers or blades), uses air power which comes from a pneumocylinder through a cooler and / or pneumatic air tank. The auxiliary power unit is equipped with a reversible invertor of the driving direction, made on the basis of a spherical slider-crank mechanism. This insures the operation of the auxiliary power unit in the mode of a pneumatic motor or compressor in accordance with the algorithm generated by the electronic control unit of the combined power plant of the vehicle. To utilize the heat energy of the exhaust fumes of the main power unit, the combined power plant is additionally equipped with a Stirling engine or steam generation module and a steam engine; in order to break energy recuperation of the vehicle it is additionally equipped with a hydraulic or electrodrive. Naturally, when choosing the specific forms of application of combined cycle power plants, any combinations of auxiliary power units are possible. They can be supplemented and / or specified based on the knowledge of specialists. Combined cycle power plants are technically complete solution. Their industrial applicability is obvious and is substantiated by experiments. Nowadays, the creation of a combined cycle power plants of a vehicle, which are a combination of several engines operating on different physical principles is the task of great economic importance. Combined power plants this allows to reduce fuel consumption per 100 km significantly, increase energy potential, horsepower characteristic and improve the environmental performance of the vehicle. The work is planned to be continued in the direction of optimization synthesis of auxiliary power units that work on different physical principles.

Finite-time thermodynamics and exergy analysis of a Stirling engine for space power generation

In recent years, the interest of space agencies and private companies in space exploration has increased, mainly in deep space missions. This type of mission poses great challenges due to the high energy level demanded from the power systems, requiring a more efficient and compact energy conversion system. Thus, this work carried out a finite-time thermodynamic model and exergy analysis of a Stirling cycle for nuclear space power generation. The thermodynamic model was coupled to a simple dynamic Stirling engine model and takes into account several aspects such as the thermal losses between the hot and cold side of the Stirling cycle, finite-time regeneration, temperature drop along heat pipes, and variable compression ratio. The system performance and component irreversibilities were evaluated by varying the nuclear core temperature and the cold side temperature of the cycle. Then, the figure of merit mass per power output (kg.kW-1) of the energy conversion system was computed, enabling the model to find temperature conditions for a system that aligns high efficiency and compactness. The results showed that the component with the greatest irreversibility is the reactor core with a value of 496.14 kJ, representing 68.18% of the total irreversibility. The exergy analysis showed that only 5.15% of the total exergy is used for power generation and 24.33% is rejected to space. Moreover, the cold side temperature of 352 K provided the system with the lowest value of mass per power output (87.69 kg.kW-1).

The effect of fire location and the reverse stack on fire smoke transport in high-rise buildings

In this paper, smoke transport in high-rise buildings through elevator shafts and stairwells is investigated for various fire location and stack effect conditions. For this purpose, a transient network model, Fire-STORM, is upgraded and used. The results are benchmarked by using a computational fluid dynamics (CFD) model. Six scenarios are tested, which are 1st floor, mid-floor, and top-most floor fires under normal stack (cold environment) and reverse stack (hot environment) conditions. For each scenario, the time history of pressures, temperatures, and soot mass fractions in the fire floors, elevator shafts, and stairwells and the average soot mass fraction in all stories of the building are presented. Overall, Fire-STORM has reasonably good accuracy compared to CFD with significantly faster computation times (90 s on a single core vs. 4 days on 32 cores in parallel). One of the intended uses of this fast low-order model is a data generation engine for neural network modeling of high-rise building fires. As such, one of the unique features of this work is the development of a realistic random heat release rate (HRR) modeling approach created using a Gaussian process.

Generator Design Considering Mover Action to Improve Energy Conversion Efficiency in a Free-Piston Engine Generator

In a free-piston engine generator (FPEG), the power of the engine can be directly regenerated by linear generators without a crank. The mover motion of this system is interrelated with engine and power generation efficiencies due to the direct connection between the mover of the generator and the piston of the engine. The generator should be designed to improve the overall energy conversion efficiency. The dimensions and mass of the mover limit its operating stroke and drive frequency. Herein, we propose a method for designing linear generators and constructing FPEG systems, considering the mover operation to improve engine efficiency. We evaluated the effect of mover operation on the engine and generation efficiencies using thermal and electromagnetic field analysis software. The proposed design method improves the overall energy conversion efficiency compared with a generator that considers only the maximization of generation efficiency. Setting the mover operation for higher engine efficiency and designing a linear generator to realize the operation can effectively improve the energy conversion efficiency of FPEGs.

Utilization and Loss of Available Energy for Chemical Rockets in Atmospheric Flight

The physical basis and application of the fundamental relationship governing the balance and utilization of available energy for a chemical rocket operating within the atmosphere are described. The relative contributions of the thermochemical availability and the kinetic energy of the stored propellant to the overall energy availability are shown. There are optimal flight velocities for which 1) overall entropy generation is minimized and 2) effectiveness of the conversion of available energy to vehicle force power is maximized. The fundamental impacts of entropy generation within a rocket engine flowfield on energy utilization and thrust/performance characteristics of a rocket-powered vehicle are studied analytically. Highly nonlinear coupling between entropy generation in the engine and entropy generation in the wake is observed; this is true as well as for other energy utilization parameters, such as thrust losses. Representative energy utilization-based performance maps for selected (example) legacy rocket systems across altitude/flight velocity confirm the theoretical results. Propulsion models and available flight data are then used to provide the time evolution of energy utilization characteristics for the flight of Apollo 11 (Saturn V).

Моделювання течії в дворядному вентиляторі турбореактивного двоконтурного двигуна

Modern trends in the global aircraft industry are prompting aircraft engine engineers to create and develop various methods to improve the aerodynamic characteristics of turbomachines. The urgent need to improve the efficiency of new generation engines leads to a rapid increase in the bypass ratio of engines, which requires the development of fans with large diametrical dimensions and high aerodynamic perfection. Boundary layer control in turbomachines using tandem blade rows is one of the most promising ways to improve the aerodynamic characteristics of aircraft engine fans with a high bypass ratio. The work aims to evaluate the aerodynamic characteristics of a fan with a tandem impeller for a turbofan engine. Two fan impellers were investigated: a single-row and an equivalent tandem-row (the equivalence was ensured by the equality of the structural angles of the flow inlet and outlet and the equality of the chord of the profiles). The blade row consisted of 33 blades, the tip diameter at the inlet to the impeller was 2.37 m, the hub diameter was 0.652 m. The flow was simulated in the range of axial velocity at the inlet from 80 to 200 m/s at a relative rotor speed of 0.65, 0.85, and 0.9. For the investigated tandem fan impeller, the chord of the first row was 60% of the total chord of the profile, the length of the slotted channel was 10% of the total chord. The flow was simulated using a numerical experiment. When closing the system of Navier-Stokes equations, Menter's SST turbulence model was used. The computational grid is unstructured, with an adaptation of the boundary layer. The work shows that the use of a tandem impeller will improve the aerodynamic characteristics of the fan. As a result of the study, it was found that the pressure ratio in a fan with tandem impeller increases from 0.32 to 20% for an operating mode at a relative rotor speed of n=0.65, n=0.85, and n=0.9 in the range of values of the gas-dynamic flow rate function q (λ)=0.4...1. The greatest growth is observed on the left branches of the pressure lines. The obtained data on the efficiency of a fan with a tandem impeller showed that in the range of values of the gas-dynamic flow rate function q(λ)=0.4...0.6 and q(λ)=0.76...0.98 a tandem impeller is higher than the efficiency of a fan with a single-row impeller, for values of the gas-dynamic flow function q(λ)=0.64...0.76 - the efficiency of a fan with a tandem impeller is 4% less than the efficiency of a fan with a single-row impeller.

Research progress of rare earth doped thermal barrier coatings

Thermal barrier coating (TBC) is a kind of thermal insulation and protective ceramic material, which can effectively improve the working temperature and service life of aero-engine. It has important economic value and strategic position in this field. With the further improvement of thrust-to-weight ratio, the traditional YSZ coating no longer can meet the technical requirements of the new generation engine. In recent years, scholars both at home and abroad have shown that rare earth doping can improve the performance of TBCs to a certain extent. Therefore, rare earth doping modification has become the focus of the development of new high-performance TBCs. In this paper, the applications of rare earth doping in high-performance TBCs are summarized, with emphasis on the effects of rare earth doping on the mechanical, thermal-physical and corrosion resistance of TBCs to molten CMAS. The problem of performance deterioration of TBCs when rare earth is over doped and the deficiency in rare earth selection standard is discussed. Moreover, it is considered that the selection basis of rare earth doping amount and type will be the research focus of TBC materials in the next generation. How to further improves the performance of TBCs is the future development direction of rare earth doped TBCs.

Characteristic of low-density polyethylene reinforcement with nano/micro particles of carbon black: a comparative study

Purpose: Low density polyethylene is commonly used polymer in the industry because of its unique structure and excellent overall performance. LDPE, is relatively low mechanical properties and thermal stability can sometimes limit its application in industry. Therefore, the development of particulate reinforced polymer composites is one of the highly promising methodologies in the area of next generation engineering products. Design/methodology/approach: Nano and Micro composite from low density polyethylene LDPE reinforced with different weight fraction of carbon black particles (CB) (2, 4 and 8)% prepared by first dispersion Nano and Micro carbon black particles CB in solvent and then mixing manually with low density polyethylene LDPE pellet and blended by twin-screw extruder, the current research study the mechanical properties (tensile strength, elastic modulus,and hardness), FTIR, DSC,and thermal conductivity of prepared nano and micro composites using two methodes and the morphological properties of nano-micro composites. Findings: The tensile strength of the LDPE/CB nano and micro composites improved at 2% and 4%, respectively, and decreasing at 8%, addition of carbon black nanoparticles led to increase the tensile strength of pure low-density polyethylene from 13.536 MPa to 19.71 MPa, and then dropping to 11.03 MPa at 8% percent,while the elastic modulus of LDPE/ CB nano and miro composites shows an improvement with all percentages of CB. The results show that the mechanical properties were improved by the addition carbon black nanoparticles more than addition micro- carbon black . FTIR show that physical interaction between LDPE and carbon black. The thermal conductivity improvement from 0.33 w/m.k for pur LDPE to 0.62234 w/m.k at 2% CB microparticle content and the reduced to 0.18645 w/m.k and 0.34063 w/m.k at (4 and 8)% micro-CB respectively , The thermal conductivity of LDPE-CB nano-composites is low in general than that the LDPE-CB microcomposite. DSC result show improvement in crystallization temperature Tc, melting temperature and degree of crystallization with addition nano and micro carbon black. Morever, SEM images revealed to uniform distribution and good bonding between LDPE and CB at low percentages and the precence of some agglomeration at high CB content.Research limitations/implications: This research studied the characteristics of both nano and micro composite materials prepared by two steps: mixing CB particles with solvent and then prepared by twin extruder which can be used packaging material, but the main limitation was the uniform distribution of nano and micro CB particles within the LDPE matrix. In a further study, prepare a blend from LDPE with other materials and improve the degradation of the blend that used in packaging application. Originality/value: LDPE with nanocomposites are of great interest because of their thermal stability, increased mechanical strength, stiffness, and low gas permeability, among other properties that have made them ideal for applications in the packaging and automotive industries. LDPE reinforcements nano-sized carbon black can have better mechanical and thermal properties than micron, resulting in less material being needed for a given application at a lower cost.

Environment-dependent vibrational heat transport in molecular junctions: Rectification, quantum effects, vibrational mismatch.

Vibrational heat transport in molecular junctions is a central issue in different contemporary research areas such as chemistry, materials science, mechanical engineering, thermoelectrics, and power generation. Our model system consists of a chain of molecules which are sandwiched between two solids that are maintained at different temperatures. We employ a quantum self-consistent reservoir model, which is built on a generalized quantum Langevin equation, to investigate quantum effects and far from equilibrium conditions on thermal conduction at nanoscale. The present self-consistent reservoir model can easily mimic the phonon-phonon scattering mechanisms. Different thermal environments are modeled as (i) Ohmic, (ii) sub-Ohmic, and (iii) super-Ohmic environments, and their effects are demonstrated for the thermal rectification properties of the system with spring graded or mass graded features. The behavior of heat current across molecular junctions as a function of chain length, temperature gradient, and phonon scattering rates are studied. Further, our analysis reveals the effects of vibrational mismatch between the solids phonon spectra on heat transfer characteristics in molecular junctions for different thermal environments.

CORRELATION BETWEEN CUTTING TEMPERATURES AND METALLURGICAL PROPERTIES OF COMPACTED GRAPHITE CAST IRONS IN THE END MILLING PROCESS

In the search for more energy-efficient internal combustion engines, the automotive companies keep pushing the working temperatures and pressures of the engines, leading to more extreme working conditions and so the necessity of new materials. Among the most promising materials for the new generations of engines is the compacted graphite cast iron, which is more wear-resistant than aluminum and tougher than gray cast iron. However, this combination of properties also leads to decreased machinability, increasing production costs and, therefore, their market competitiveness. This paper evaluated the correlation of mechanical and metallurgical properties and the cutting power and surface roughness of three grades of compacted graphite cast iron with the cutting temperature in the end milling process under different two different feed rates and cutting speeds. This analysis showed that the temperatures near the cutting zone are closely correlated to the material's mechanical properties, machining power, and resulting roughness. These results indicate that thermographic images are a good indicator of the overall correlation between the changes in material properties and the most usual machinability output parameters.

SELECTION OF REFERENCE SYSTEM ELEMENTS IN THE MODEL OF PGE - PRODUCT GENERATION ENGINEERING: METHOD FOR THE INTEGRATION OF CUSTOMER AND USER SATISFACTION IN PRODUCT PLANNING

AbstractIn the development of mechatronic systems, it is important to differentiate the products to be developed from those of the competitors, but also from the own product generations already available on the market. However, there are uncertainties regarding the correct features to be differentiated from the customer and user perspective and how these features should be designed. Nevertheless, despite the high impact, decisions must be taken early in the development process. Within this publication, a method to support in this respect was derived based on the findings of the Model of PGE - Product Generation Engineering and the Kano-Model. Therefore, experienceable product features and reference system elements as characteristics of these are evaluated according to the Kano-Model and thus made comparable with regard to the customers and user satisfaction. The objective is to select the product features to be differentiated and the corresponding reference system elements in such a way that a desired level of customer and user satisfaction is achieved. In order to evaluate the method, it was applied in a real development project. It was found that the application of the method led to a reduction of the existing uncertainty.

MODELLING AND VISUALIZING KNOWLEDGE ON THE REFERENCE SYSTEM AND VARIATIONS BASED ON THE MODEL OF PGE – PRODUCT GENERATION ENGINEERING FOR DECISION SUPPORT

AbstractIn 2019, Dyson had to cancel its ambitious electric car project after having already 500 Million pounds spent. This example shows how difficult it is to assess the consequences of decisions on development targets as cost, risk, and innovation potential. Knowledge about references, variation types and their impact on development targets can help to increase the maturity of the decision basis. The model of PGE - product generation engineering describes these interrelations using the reference system. This contribution deals with the question of how knowledge about the impact of variation types and characteristics of reference system elements on new product generations can be made usable through modelling and visualization. Therefore, characteristics of reference system elements and their impacts on common development targets are collected through literature research. To process this knowledge base in technical information systems, an Entity-Relationship data model is developed. Through the implementation of a VR visualization, the data model is validated and a first visualisation approach is shown. The findings of this work can be used to systematise research on impact factors in PGE and to develop further digital methods.