FEM Simulation as an Element Based on Infill Pattern Structures Fabricated with CFRP-AM

Coumarins are natural 1,2-benzopyrones, present in remarkable amounts as secondary metabolites in edible and medicinal plants. The low yield in the coumarins isolation from natural sources, along with the difficulties faced by the total synthesis, make them attractive for biotechnological studies. The current literature contains several reports on the biotransformation of coumarins by fungi, which can generate chemical analogs with high selectivity, using mild and eco-friendly conditions. Prompted by the enormous pharmacological interest in the coumarin-related compounds, their alimentary and chemical applications, this review covers the biotransformation of coumarins by filamentous fungi. The chemical structures of the analogs were presented and compared with those from the pattern structures. The main chemical reactions catalyzed the insertion of functional groups, and the impact on the biological activities caused by the chemical transformations were discussed. Several chemical reactions can be catalyzed by filamentous fungi in the coumarin scores, mainly lactone ring opening, C3-C4 reduction and hydroxylation. Chunninghamella sp. and Aspergillus sp. are the most common fungi used in these transformations. Concerning the substrates, the biotransformation of pyranocoumarins is a rarer process. Sometimes, the bioactivities were improved by the chemical modifications and coincidences with the mammalian metabolism were pointed out.

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FEM-SIMULATION OF LAMINAR FLAME PROPAGATION II: TWIN AND TRIPLE FLAMES IN COUNTERFLOW

Combustion Science and Technology ◽

10.1080/00102200590926941 ◽

2005 ◽

Vol 177 (5-6) ◽

pp. 955-978 ◽

Cited By ~ 8

Author(s):

B. MICHAELIS ◽

B. ROGG

Keyword(s):

Flame Propagation ◽

Laminar Flame ◽

Fem Simulation

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Modeling the Piezoelectric Cantilever Resonator with Different Width Layers

Sensors ◽

10.3390/s21010087 ◽

2020 ◽

Vol 21 (1) ◽

pp. 87

Author(s):

Zhenxi Liu ◽

Jiamin Chen ◽

Xudong Zou

Keyword(s):

Resonance Frequency ◽

Integrated Circuit ◽

Silicon Oxide ◽

Fem Simulation ◽

Control Process ◽

Design Tool ◽

Piezoelectric Cantilever ◽

Simulation And Experiment ◽

Easy Integration ◽

Tip Displacement

The piezoelectric cantilever resonator is used widely in many fields because of its perfect design, easy-to-control process, easy integration with the integrated circuit. The tip displacement and resonance frequency are two important characters of the piezoelectric cantilever resonator and many models are used to characterize them. However, these models are only suitable for the piezoelectric cantilever with the same width layers. To accurately characterize the piezoelectric cantilever resonators with different width layers, a novel model is proposed for predicting the tip displacement and resonance frequency. The results show that the model is in good agreement with the finite element method (FEM) simulation and experiment measurements, the tip displacement error is no more than 6%, the errors of the first, second, and third-order resonance frequency between theoretical values and measured results are 1.63%, 1.18%, and 0.51%, respectively. Finally, a discussion of the tip displacement of the piezoelectric cantilever resonator when the second layer is null, electrode, or silicon oxide (SiO2) is presented, and the utility of the model as a design tool for specifying the tip displacement and resonance frequency is demonstrated. Furthermore, this model can also be extended to characterize the piezoelectric cantilever with n-layer film or piezoelectric doubly clamped beam.

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Random impact FEM simulation of irregularly-shaped media for parametric study of vibratory surface enhancement

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405421990128 ◽

2021 ◽

pp. 095440542199012

Author(s):

Jing Zhang ◽

Joselito Yam Alcaraz ◽

Swee-Hock Yeo ◽

Arun Prasanth Nagalingam ◽

Abhay Gopinath

Keyword(s):

Residual Stress ◽

Fatigue Life ◽

Parametric Study ◽

Thermal Loading ◽

Low Cycle Fatigue ◽

Fem Simulation ◽

Surface Finishing ◽

Aerospace Materials ◽

Surface Enhancement ◽

Steel Balls

Aerospace materials experience high levels of mechanical and thermal loading, high/low cycle fatigue, and damage from foreign objects during service, which can lead to premature retirement. Mechanical surface treatments of metallic components, for example, fan blades and blisks, are proven to improve fatigue life, improve wear resistance and avoid stress corrosion by introducing work hardening, compressive residual stresses of sub-surface, and surface finishing. Vibropeening can enhance aerospace materials’ fatigue life involving the kinetic agitation of hardened steel media in a vibratory finishing machine that induces compressive stresses into the component sub-layers while keeping a finished surface. Spherical steel balls are the most widely used shape among steel-based media and have been explored for decades. However, they are not always versatile, which cannot access deep grooves, sharp corners, and intricate profiles. Steel ballcones or satellites, when mixed with round steel balls and other steel media (diagonals, pins, eclipses, cones), works very well in such areas that ball-shaped media are unable to reach. However, a methodology of study the effect of irregularly-shaped media in surface enhancement processes has not been established. This paper proposes a finite element-based model to present a methodology for the parametric study of vibratory surface enhancement with irregularly-shaped media and investigates residual stress profiles within a treated area of an Inconel component. The methodology is discussed in detail, which involves a stochastic simulation of orientation, impact force, and impact location. The contrasting effects of a high aspect ratio, or an edge contact, as opposed to rounded and oblique contacts are demonstrated, with further analysis on the superposition of these effects. Finally, the simulation results are compared with actual residual stress measurements and was found to have a max percent difference of 34% up to 20 [Formula: see text]m below the media surface.

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3D-FEM Simulation of Hot Rolling Process and Characterization of the Resultant Microstructure of a Light-Weight Mn Steel

Crystals ◽

10.3390/cryst11050569 ◽

2021 ◽

Vol 11 (5) ◽

pp. 569

Author(s):

Ana Claudia González-Castillo ◽

José de Jesús Cruz-Rivera ◽

Mitsuo Osvaldo Ramos-Azpeitia ◽

Pedro Garnica-González ◽

Carlos Gamaliel Garay-Reyes ◽

...

Keyword(s):

Hot Rolling ◽

Thermomechanical Processing ◽

Computational Simulation ◽

Effective Strain ◽

Fem Simulation ◽

Rolling Process ◽

3D Fem ◽

Hot Rolling Process ◽

Mn Steel

Computational simulation has become more important in the design of thermomechanical processing since it allows the optimization of associated parameters such as temperature, stresses, strains and phase transformations. This work presents the results of the three-dimensional Finite Element Method (FEM) simulation of the hot rolling process of a medium Mn steel using DEFORM-3D software. Temperature and effective strain distribution in the surface and center of the sheet were analyzed for different rolling passes; also the change in damage factor was evaluated. According to the hot rolling simulation results, experimental hot rolling parameters were established in order to obtain the desired microstructure avoiding the presence of ferrite precipitation during the process. The microstructural characterization of the hot rolled steel was carried out using optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). It was found that the phases present in the steel after hot rolling are austenite and α′-martensite. Additionally, to understand the mechanical behavior, tensile tests were performed and concluded that this new steel can be catalogued in the third automotive generation.

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Torque Ripple Reduction in PM Synchronous Motor - FEM simulation

2020 International Conference on Electrical Machines (ICEM) ◽

10.1109/icem49940.2020.9270720 ◽

2020 ◽

Author(s):

Martin Sumega ◽

Marek Stulrajter ◽

Pavol Rafajdus

Keyword(s):

Fem Simulation ◽

Torque Ripple ◽

Synchronous Motor ◽

Torque Ripple Reduction ◽

Pm Synchronous Motor ◽

Ripple Reduction

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Fem Simulation of Micro-Rotating-Structures and Their Applications in Measurement of Residual Stresses in Thin Films

MRS Proceedings ◽

10.1557/proc-505-21 ◽

1997 ◽

Vol 505 ◽

Cited By ~ 5

Author(s):

Xin Zhang ◽

Tong-Yi Zhang ◽

Yitshak Zohar

Keyword(s):

Thin Films ◽

Residual Stresses ◽

Fem Simulation ◽

Sensitivity Factor ◽

Local Measurement ◽

Micro Structure ◽

Micro Raman Spectroscopy ◽

Before And After ◽

Polysilicon Films ◽

Simulation Results

ABSTRACTFEM simulation of micro-rotating-structures was performed for local measurement of residual stresses in thin films. A sensitivity factor is introduced, studied and tabulated from the simulation results. The residual stress can be evaluated from the rotating deflection, the lengths of rotating and fixed beams, and the sensitivity factor. The micro-structure technique was applied to measure residual stresses in both silicon nitride and polysilicon thin films, before and after rapid thermal annealing (RTA), and further confirmed by wafer curvature method. Residual stresses in polysilicon films at different RTA stages were also characterized by micro-Raman spectroscopy (MRS). The experimental results indicate that micro-rotating-structures indeed have the ability to measure spatially and locally residual stresses in MEMS thin films with appropriate sensitivities.

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FDTD and FEM Simulation of Microwave Waveguide Polarizers

2020 IEEE 2nd International Conference on Advanced Trends in Information Theory (ATIT) ◽

10.1109/atit50783.2020.9349339 ◽

2020 ◽

Author(s):

Stepan Piltyay ◽

Andrew Bulashenko ◽

Yevhenii Herhil ◽

Oleksandr Bulashenko

Keyword(s):

Fem Simulation

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