Digital twin of the rotor-shaft of a lightweight electric motor during aerobatics loads

2020 ◽  
Vol 92 (9) ◽  
pp. 1319-1326
Author(s):  
Robert Goraj
Keyword(s):  
Electric Motor ◽  
Load Capacity ◽  
Safety Margin ◽  
Element Model ◽  
Load Spectrum ◽  
Content Type ◽  
Digital Twin ◽  
Motor Set ◽  
One Step ◽  
Semi Empirical

Purpose This paper aims to present airworthiness considerations regarding a shaft of an electric motor. A fatigue lifetime prediction analysis based on one-step load spectrum is performed during high-cycle fatigue. Time-dependent normal and shear stress components are estimated using a high-fidelity digital twin built in Siemens PLM Nx Nastran as a finite element model (FEM). Linear and centrifugal acceleration as well as gyroscopic moment, motor torque, propeller thrust and thermal loads are considered. The equivalent cyclic degree of utilisation and a safety margin against the slip of a press-fitted shaft to rotor hub connection is estimated. Design/methodology/approach A load analysis using FEM is presented. The numerically obtained results are verified on an analytical and a semi-empirical basis. Findings The shaft of the electric motor can sustain 74 h of operation if burdened with aerobatic loads. Its load capacity equals 48% for the overall safety factor of 2.25. Practical implications The paper presents a specific, easily identifiable advance in knowledge that can be applicable in safety flight analysis issues. Originality/value The work presents a rotor of a novel lightweight electric motor for aircraft applications, which is a successor of the electric motor set recently in Extra 330E. The work delivers a computational estimation of the shaft life.

A four-node membrane element model with bending modification for one-step algorithm for bus rollover impact

2015 ◽  
Vol 32 (3) ◽  
pp. 607-620 ◽  
Author(s):  
Jingxin Na ◽  
Tong Wang ◽  
Changfeng Wu ◽  
Yakun Yan
Keyword(s):  
Engineering Application ◽  
Element Model ◽  
Bending Moments ◽  
Membrane Element ◽  
Computational Accuracy ◽  
Content Type ◽  
One Step ◽  
Internal Forces ◽  
Step Algorithm ◽  
The One

Purpose – The purpose of this paper is to propose a new four-node membrane element model with bending modification based on the equilibrium principle of element nodal internal forces and bending moments for the application of the one-step algorithm for bus rollover collision. And it can be concluded whether the proposed four-node membrane element model has practical value in engineering application or not. Design/methodology/approach – Based on the equilibrium principle of element nodal internal forces and bending moments, the paper puts forward a four-node membrane element model with bending modification. A case study on the rollover of a typical bus body section is carried out by using the one-step algorithm for bus rollover collision to verify the effectiveness of the proposed element model. Findings – For the simulation of bus rollover collision, the computational accuracy can be guaranteed, meanwhile, the calculated amount is much smaller than the shell element, and computational efficiency is improved significantly. Originality/value – The proposed four-node membrane element model is used for the simulation of bus rollover collision for the first time. It holds the advantage of high computational efficiency of membrane element, and the computational accuracy is improved as well. In conclusion, it has some practical value in engineering application.

scholarly journals Understanding design change propagation in complex engineering systems using a digital twin and design structure matrix

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Long Chen ◽  
Jennifer Whyte
Keyword(s):  
Large Scale ◽  
Load Capacity ◽  
Prediction Method ◽  
Change Propagation ◽  
Engineering Systems ◽  
Content Type ◽  
Design Change ◽  
Digital Twin ◽  
Complex Engineering ◽  
Complex Engineering Systems

PurposeAs the engineering design process becomes increasingly complex, multidisciplinary teams need to work together, integrating diverse expertise across a range of disciplinary models. Where changes arise, these design teams often find it difficult to handle these design changes due to the complexity and interdependencies inherent in engineering systems. This paper aims to develop an innovative approach to clarifying system interdependencies and predicting the design change propagation at the asset level in complex engineering systems based on the digital-twin-driven design structure matrix (DSM).Design/methodology/approachThe paper first defines the digital-twin-driven DSM in terms of elements and interdependencies, where the authors have defined three types of interdependency, namely, geospatial, physical and logical, at the asset level. The digital twin model was then used to generate the large-scale DSMs of complex engineering systems. The cluster analysis was further conducted based on the improved Idicula–Gutierrez–Thebeau algorithm (IGTA-Plus) to decompose such DSMs into modules for the convenience and efficiency of predicting design change propagation. Finally, a design change propagation prediction method based on the digital-twin-driven DSM has been developed by integrating the change prediction method (CPM), a load-capacity model and fuzzy linguistics. A section of an infrastructure mega-project in London was selected as a case study to illustrate and validate the developed approach.FindingsThe digital-twin-driven DSM has been formally defined by the spatial algebra and Industry Foundation Classes (IFC) schema. Based on the definitions, an innovative approach has been further developed to (1) automatically generate a digital-twin-driven DSM through the use of IFC files, (2) to decompose these large-scale DSMs into modules through the use of IGTA-Plus and (3) predict the design change propagation by integrating a digital-twin-driven DSM, CPM, a load-capacity model and fuzzy linguistics. From the case study, the results showed that the developed approach can help designers to predict and manage design changes quantitatively and conveniently.Originality/valueThis research contributes to a new perspective of the DSM and digital twin for design change management and can be beneficial to assist designers in making reasonable decisions when changing the designs of complex engineering systems.

scholarly journals Synthesis of Artemiside and Its Effects in Combination with Conventional Drugs against Severe Murine Malaria

2011 ◽  
Vol 56 (1) ◽  
pp. 163-173 ◽  
Author(s):  
Jin Guo ◽  
Armand W. Guiguemde ◽  
Annael Bentura-Marciano ◽  
Julie Clark ◽  
Richard K. Haynes ◽  
...  
Keyword(s):  
Safety Margin ◽  
Drug Combinations ◽  
Parasite Development ◽  
Content Type ◽  
Drug Concentrations ◽  
One Step ◽  
High Concentrations ◽  
Malaria Model

ABSTRACTThis research describes the use of novel antimalarial combinations of the new artemisinin derivative artemiside, a 10-alkylamino artemisinin. It is a stable, highly crystalline compound that is economically prepared from dihydroartemisinin in a one-step process. Artemiside activity was more pronounced than that of any antimalarial drug in use, both inPlasmodium falciparumculture andin vivoin a murine malaria model depicting cerebral malaria (CM).In vitrohigh-throughput testing of artemiside combinations revealed a large number of conventional antimalarial drugs with which it was additive. Following monotherapy in mice, individual drugs reduced parasitemias to nondetectable levels. However, after a period of latency, parasites again were seen and eventually all mice became terminally ill. Treatment with individual drugs did not prevent CM in mice with recrudescent malaria, except for piperaquine at high concentrations. Even when CM was prevented, the mice developed later of severe anemia. In contrast, most of the mice treated with drug combinations survived. A combination of artemiside and mefloquine or piperaquine may confer an optimal result because of the longer half life of both conventional drugs. The use of artemiside combinations revealed a significant safety margin of the effective artemiside doses. Likewise, a combination of 1.3 mg/kg of body weight artemiside and 10 mg/kg piperaquine administered for 3 days from the seventh day postinfection was completely curative. It appears possible to increase drug concentrations in the combination therapy without reaching toxic levels. Using the drug combinations as little as 1 day before the expected death of control animals, we could prevent further parasite development and death due to CM or anemic malaria. Earlier treatment may prevent cognitive dysfunctions which might occur after recovery from CM.

Investigation on the shaft voltage generation of large synchronous turboalternators

2020 ◽  
Vol 39 (5) ◽  
pp. 1145-1156
Author(s):  
Kevin Darques ◽  
Abdelmounaïm Tounzi ◽  
Yvonnick Le-menach ◽  
Karim Beddek
Keyword(s):  
Finite Element ◽  
Design Methodology ◽  
Short Circuit ◽  
Element Model ◽  
Stator Winding ◽  
Content Type ◽  
Voltage Generation ◽  
The Impact ◽  
Investigation Process ◽  
Circulating Currents

Purpose This paper aims to go deeper on the analysis of the shaft voltage of large turbogenerators. The main interest of this study is the investigation process developed. Design/methodology/approach The analysis of the shaft voltage because of several defects is based on a two-dimensional (2D) finite element modeling. This 2D finite element model is used to determine the shaft voltage because of eccentricities or rotor short-circuit. Findings Dynamic eccentricities and rotor short circuit do not have an inherent impact on the shaft voltage. Circulating currents in the stator winding because of defects impact the shaft voltage. Originality/value The original value of this paper is the investigation process developed. This study proposes to quantify the impact of a smooth stator and then to explore the contribution of the real stator winding on the shaft voltage.

scholarly journals Squalene-Hopene Cyclases

2011 ◽  
Vol 77 (12) ◽  
pp. 3905-3915 ◽  
Author(s):  
Gabriele Siedenburg ◽  
Dieter Jendrossek
Keyword(s):  
Common Ancestor ◽  
Amino Acid Sequences ◽  
Enzymatic Reactions ◽  
Covalent Bonds ◽  
Content Type ◽  
Oxidosqualene Cyclase ◽  
Ring Structures ◽  
One Step ◽  
Alicyclobacillus Acidocaldarius ◽  
Eukaryotic Organisms

ABSTRACTHopanoids and sterols are members of a large group of cyclic triterpenoic compounds that have important functions in many prokaryotic and eukaryotic organisms. They are biochemically synthesized from linear precursors (squalene, 2,3-oxidosqualene) in only one enzymatic step that is catalyzed by squalene-hopene cyclase (SHC) or oxidosqualene cyclase (OSC). SHCs and OSCs are related in amino acid sequences and probably are derived from a common ancestor. The SHC reaction requires the formation of five ring structures, 13 covalent bonds, and nine stereo centers and therefore is one of the most complex one-step enzymatic reactions. We summarize the knowledge of the properties of triterpene cyclases and details of the reaction mechanism ofAlicyclobacillus acidocaldariusSHC. Properties of other SHCs are included.

Investigation of slip/no-slip surface for two-dimensional large tilting pad thrust bearing

2017 ◽  
Vol 69 (6) ◽  
pp. 995-1004 ◽  
Author(s):  
Zhixiang Song ◽  
Fei Guo ◽  
Ying Liu ◽  
Songtao Hu ◽  
Xiangfeng Liu ◽  
...  
Keyword(s):  
Reynolds Number ◽  
Slip Surface ◽  
Load Capacity ◽  
Slip Condition ◽  
Optimized Design ◽  
Two Dimensional ◽  
Boundary Slip ◽  
Content Type ◽  
Tilting Pad ◽  
Turbulence Effect

Purpose This paper aims to present the slip/no-slip design in two-dimensional water-lubricated tilting pad thrust bearings (TPTBs) considering the turbulence effect and shifting of pressure centers. Design/methodology/approach A numerical model is established to analyze the slip condition and the effect of turbulence according to a Reynolds number defined in terms of the slip condition. Simulations are carried out for eccentrically and centrally pivoted bearings and the influence of different slip parameters is discussed. Findings A considerable enhancement in load capacity, as well as a reduction in friction, can be achieved by heterogeneous slip/no-slip surface designs for lubricated sliding contacts, especially for near parallel pad configurations. The optimized design largely depends on the pivot position. The load capacity increases by 174 per cent for eccentrically pivoted bearings and 159 per cent for centrally pivoted bearings for a suitable design. When slip zone locates at the middle of the radial direction or close to the inner edge, the performance of the TPTB is better. Research limitations/implications The simplification of slip effect on the turbulence (definition of Reynolds number) can only describe the trend of the increasing turbulence due to slip condition. The accurate turbulence expression considering the boundary slip needs further explorations. Originality/value The shifting of pressure center due to the slip/no-slip design for TPTBs is investigated in this study. The turbulence effect and influence of slip parameters is discussed for large water-lubricated bearings.

A coupled FE model for the joint resolution of the shallow water and the groundwater flow equations

2014 ◽  
Vol 24 (7) ◽  
pp. 1553-1569 ◽  
Author(s):  
H.G. Rábade ◽  
P. Vellando ◽  
F. Padilla ◽  
R. Juncosa
Keyword(s):  
Groundwater Flow ◽  
Shallow Water ◽  
Free Surface Flow ◽  
Element Model ◽  
Surface Flow ◽  
Fe Model ◽  
Content Type ◽  
Flow Equations ◽  
Natural Watersheds ◽  
Joint Resolution

Purpose – A new coupled finite element model has been developed for the joint resolution of both the shallow water equations, that governs the free surface flow, and the groundwater flow equation that governs the motion of water through a porous media. The paper aims to discuss these issues. Design/methodology/approach – The model is based upon two different modules (surface and ground water) previously developed by the authors, that have been validated separately. Findings – The newly developed software allows for the assessment of the fluid flow in natural watersheds taking into account both the surface and the underground flow in the way it really takes place in nature. Originality/value – The main achievement of this work has dealt with the coupling of both models, allowing for a proper moving interface treatment that simulates the actual interaction that takes place between surface and groundwater in natural watersheds.

scholarly journals One-Step Multiplex PCR Assay for Differentiating Proposed New Species “Clostridium neonatale” from Closely Related Species

2015 ◽  
Vol 53 (11) ◽  
pp. 3621-3623 ◽  
Author(s):  
Laurent Ferraris ◽  
Sophia Schönherr ◽  
Philippe Bouvet ◽  
Brunhilde Dauphin ◽  
Michel Popoff ◽  
...  
Keyword(s):  
New Species ◽  
Sensu Stricto ◽  
Preterm Neonates ◽  
Content Type ◽  
Colony Pcr ◽  
Multiplex Pcr Assay ◽  
Colonization Frequency ◽  
Content Identification ◽  
One Step ◽  
Neonatal Necrotizing Enterocolitis

“Clostridium neonatale” sp. nov., previously involved in an outbreak of neonatal necrotizing enterocolitis, was recently proposed as a new species of theClostridiumgenussensu stricto. We developed a one-step multiplex colony PCR forC. neonataleidentification and investigatedC. neonataleintestinal colonization frequency in healthy preterm neonates.

An analytical model for the behavior of I-shaped beam to cylindrical column connections at room temperature and high temperatures

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Seied Ahmad Hosseini ◽  
Mostafa Zeinoddini
Keyword(s):  
Analytical Solution ◽  
Elevated Temperatures ◽  
Element Model ◽  
Small Scale ◽  
Offshore Platforms ◽  
Rotational Stiffness ◽  
Rotation Curves ◽  
Content Type ◽  
Shaped Beam ◽  
Cylindrical Column

PurposeIn this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, are presented.Design/methodology/approachAn analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections is presented. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors.FindingsIn this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, is presented. The required yield and plastic moments in this model are provided as an extension to Roark's relationships. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors. A reasonable agreement has been found between the analytical model results and the experimental/numerical modeling results.Originality/valueThis article is extracted from the author’s doctoral thesis, and all its achievements belong to the authors of the article.

Influence of different flow regimes on the performance characteristics of a four-pad hydrostatic squeeze film damper loaded between pads

2019 ◽  
Vol 71 (3) ◽  
pp. 440-446
Author(s):  
Amina Nemchi ◽  
Ahmed Bouzidane ◽  
Aboubakeur Benariba ◽  
Hicham Aboshighiba
Keyword(s):  
Turbulent Flow ◽  
Load Capacity ◽  
Flow Regimes ◽  
Performance Characteristics ◽  
Squeeze Film ◽  
Eccentricity Ratio ◽  
Flow Conditions ◽  
Content Type ◽  
Turbulent Flow Regime ◽  
Squeeze Film Dampers

Purpose The purpose of this paper is to study the influence of different flow regimes on the dynamic characteristics of four-pad hydrostatic squeeze film dampers (SFDs) loaded between pads. Design/methodology/approach A numerical model based on Constantinescu’s turbulent lubrication theory using the finite difference method has been developed and presented to study the effect of eccentricity ratio on the performance characteristics of four-pad hydrostatic SFDs under different flow regimes. Findings It was found that the influence of turbulent flow on the dimensionless damping of four-pad hydrostatic SFDs appears to be essentially controlled by the eccentricity ratio. It was also found that the laminar flow presents higher values of load capacity compared to bearings operating under turbulent flow conditions. Originality/value In fact, the results obtained show that the journal bearing performances are significantly influenced by the turbulent flow regime. The study is expected to be useful to bearing designers.

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