Lightning strike damage can severely affect the thermo-mechanical performance of composite laminates. It is essential to quantify the effect of lightning strikes considering the inevitable influence ...of material and geometric uncertainties for ensuring the operational safety of aircraft. This paper presents an efficient support vector machine (SVM)-based surrogate approach coupled with computationally intensive transient thermal-electrical finite element simulations to quantify the uncertainty in lightning strike damage. The uncertainty in epoxy matrix thermal damage and electrical responses of unprotected carbon/epoxy composite laminates is probabilistically quantified considering the stochasticity in temperature-dependent multi-physical material properties and ply orientations. Further, the SVM models are exploited for variance-based global sensitivity analysis to investigate the input parameters' relative influence on the lightning strike-induced damage behavior. Due to the adoption of a coupled SVM-based simulation approach here, it has become possible to carry out a comprehensive uncertainty quantification leading to complete probabilistic descriptions of the electrical and lightning damage parameters despite the requirement of performing a large number of computationally intensive function evaluations. The results reveal that source-uncertainty of the unprotected laminates significantly influences the epoxy matrix decomposition, electrical current density and electric potential, wherein longitudinal electrical conductivity is most sensitive to stochastic variations followed by other electrical, thermal and geometric parameters.
Electric vehicle (EV) fleet is constantly increasing over the years and higher adoption is expected in the coming decades. A key aspect to support and boost the EV uptake is the adequate availability ...(number, locations and sizes) of fast charging stations (FCSs) to enable inter- and intra-city travels. Since these studies require modelling large regions with uncertainties, a methodology able to provide the least-cost solution is needed. This study proposes a scalable methodology that integrates high-resolution traffic flow and multi-phase electrical simulations to find the number, locations and sizes of FCSs at the least societal cost considering the uncertainties in driving patterns. It determines potential FCSs locations based on traffic flow and progressively explores these FCSs quantifying capital (equipment and land) and indirect (loss of productivity and reinforcements) costs to identify the least-cost solution. Results from a Brazilian case study comprising of a metropolitan region with six cities and 26 primary substations show that, with high adoption of EVs, the investments in equipment represent the most significant components of societal cost. Moreover, for metropolitan regions, the societal least-cost solution is found with more but smaller FCSs. Finally, is found that neglecting the loss of productivity can significantly affect the results.
Fast changing irradiation on vehicle‐integrated photovoltaic (VIPV) modules may impose demanding requirements for maximum power point tracking (MPPT) to ensure high energy conversion efficiency. In ...this work, the results of simulations regarding the output and efficiency of an exemplary VIPV module under real‐life irradiation conditions as measured with high time resolution are resulted. Herein, resistive as well as voltage source load is used as two idealized models of the MPPT. The simulations show that, in most cases, tracking with a resistive load at 1 Hz preserves above 90%rel of the convertible energy determined by the cell performances under given irradiance levels. With a voltage source load, these values do not undercut 97%rel at 0.1 Hz. Herein, it is also found that partial shading across the exemplary series connected module can reduce the converted energy in the range of 5–10%rel in relation to complete negligence of this effect.
The performance of vehicle‐integrated photovoltaics and demands on maximum power point tracking is evaluated with high‐resolution irradiation data and transient electrical modelling. Voltage based tracking yields significantly better results than resistance‐based tracking and in both cases 1 Hz tracking frequency preserves above 90% of convertible electrical energy. Partial shading makes up for losses up to 10%.
Interface recombination in sub-mu m optoelectronics has a major detrimental impact on devices' performance, showing the need for tailored passivation strategies to reach a technological boost. In ...this article, SiO$_x$ passivation based substrates were developed and integrated into ultrathin Cu(In,Ga)Se$_2$ (CIGS) solar cells. This article aims to understand the impact of a passivation strategy, which uses several SiO$_x$ layer thicknesses (3, 8, and 25 nm) integrated into high-performance substrates (HPS). The experimental study is complemented with 3-D lumerical finite-difference time-domain and 2-D Silvaco ATLAS optical and electrical simulations, respectively, to perform a decoupling of optical and electronic gains, allowing for a deep discussion on the impact of the SiO$_x$ layer thickness in the CIGS solar cell performance. This article shows that as the passivation layer thickness increases, a rise in parasitic losses is observed. Hence, a balance between beneficial passivation and optical effects with harmful architectural constraints defines a threshold thickness to attain the best solar cell performance. Analyzing their electrical parameters, the 8-nm novel SiO$_x$ based substrate achieved a light to power conversion efficiency value of 13.2%, a 1.3% absolute improvement over the conventional Mo substrate (without SiO$_x$).
The aim of this project is the use of Aluminum material as alternative in thermomagnetic trip units (TMTU) instead of Copper. This alternative material has showed similar performance in comparison ...with the common material used for this application. The mechanical and physical properties of both materials were evaluated to establish the specific alloy which could accomplish the target for this application. Thermo-electrical analysis simulations made with ANSYS software shows a similar performance between Cu CDA 260 and Al 5052, with a difference around 2.5~2.9% of the measured temperature during thermo-electrical tests. The response time between both materials was similar and into the established range during the test. The Al 5052 exhibit stable performance at the TMTU, with the advantages related with the material itself.
Interface recombination in sub-μm optoelectronics has a major detrimental impact on devices' performance, showing the need for tailored passivation strategies to reach a technological boost. In this ...article, SiO x passivation based substrates were developed and integrated into ultrathin Cu(In,Ga)Se 2 (CIGS) solar cells. This article aims to understand the impact of a passivation strategy, which uses several SiO x layer thicknesses (3, 8, and 25 nm) integrated into high-performance substrates (HPS). The experimental study is complemented with 3-D lumerical finite-difference time-domain and 2-D Silvaco ATLAS optical and electrical simulations, respectively, to perform a decoupling of optical and electronic gains, allowing for a deep discussion on the impact of the SiO x layer thickness in the CIGS solar cell performance. This article shows that as the passivation layer thickness increases, a rise in parasitic losses is observed. Hence, a balance between beneficial passivation and optical effects with harmful architectural constraints defines a threshold thickness to attain the best solar cell performance. Analyzing their electrical parameters, the 8-nm novel SiO x based substrate achieved a light to power conversion efficiency value of 13.2%, a 1.3% absolute improvement over the conventional Mo substrate (without SiO x ).
► Tunable WDM converters based on SiC multilayer photonic active filters are analyzed. ► Integrated active long,- and short-pass wavelength filters into capacitive band-pass filters. ► The photonic ...device combines the demultiplexing operation with the simultaneous photodetection and self amplification of an optical signal. ► The wavelength background and irradiation side control the filter characteristics. ► A numerical simulation and a two building-blocks active circuit are presented.
Combined tunable WDM converters based on SiC multilayer photonic active filters are analyzed. The operation combines the properties of active long-pass and short-pass wavelength filter sections into a capacitive active band-pass filter.
The sensor element is a multilayered heterostructure produced by PE-CVD. The configuration includes two stacked SiC p–i–n structures sandwiched between two transparent contacts. Transfer function characteristics are studied both theoretically and experimentally.
Results show that optical bias activated photonic device combines the demultiplexing operation with the simultaneous photodetection and self amplification of an optical signal acting the device as an integrated photonic filter in the visible range. Depending on the wavelength of the external background and irradiation side, the device acts either as a short- or a long-pass band filter or as a band-stop filter. The output waveform presents a nonlinear amplitude-dependent response to the wavelengths of the input channels. A numerical simulation and a two building-blocks active circuit are presented and give insight into the physics of the device.
Tunable wavelength division multiplexing converters based on amorphous SiC multilayer photonic active filters are analyzed. The configuration includes two stacked p-i-n structures ...(p(a-SiC:H)-í'(a-SiC:H)-n(a-SiC:H)-p(a-SiC:H)-i(a-Si:H)-n(a-Si:H)) sandwiched between two transparent contacts. The manipulation of the magnitude is achieved through appropriated front and back backgrounds. Transfer function characteristics are studied both theoretically and experimentally. An algorithm to decode the multiplex signal is established. An optoelectronic model supports the optoelectronic logic architecture. Results show that the light-activated device combines the demultiplexing operation with the simultaneous photodetection and self-amplification of an optical signal. The output waveform presents a nonlinear amplitude-dependent response to the wavelengths of the input channels. Depending on the wavelength of the external background and irradiation side, it acts either as a short- or a long-pass band filter or as a band-stop filter. A two-stage active circuit is presented and gives insight into the physics of the device.
Vertical Nanowire Field Effect Transistors (VN-WFETs) are an emerging technology with significant potential to reduce footprint and consequently interconnect capacitance, thereby achieving improved ...energy-efficiency and being naturally compatible with advanced 3D integration approaches. However, while initial estimations have focused on projections and estimations, no work has so far used a detailed compact model to attempt accurate transistor-level simulations for standard cell library characterization thus enabling logic synthesis. In this paper, we propose a design flow to make the link from an existing (laboratory-scale) VNWFET technology and the associated compact model, to standard static logic cell design and characterization, and ultimately logic synthesis. To the best of our knowledge, this is the first work to prove the possibility of such a realistic design flow tailored to VNWFET technologies.
An adjustable capacitor generally consists in a stator and a rotor. The stator is made of the dielectric tube and the fixed electrode which is affixed in the outer. The rotor is the conductive body ...that acts as the variable electrode, and it moves axially in the housing. Furthermore, this entire structure is held together with a combination of screws, clips, soldering and other connection mechanisms. As a composed component, manufacturing time and cost increase. These capacitors are made for sharp domains that require their own conditions. These constraints need additional steps in the manufacturing process and increase the percentage of device failures, so this also drives down the profitability of the process.In order to create a new range of non-magnetic trimmers (adjustable capacitors) more performant to meet the Nuclear magnetic resonance (NMR) requirements, as MRI (Magnetic Resonance Imaging) applications, electrical modeling is an important step to improve empirical research results so to provide a high level of quality and to reduce manufacturing time and cost while.In this context ANSYS is used to design innovative electromechanical devices, simulate electrostatic performance of the component and then estimate a large number of trimmer parameters (material properties, capacitance value, breakdown voltage) and anticipate critical electrical effects (corona, point and edge effects).