Search results for "Time domain analysis"

showing 4 items of 4 documents

Controlled time integration for the numerical simulation of meteor radar reflections

2016

We model meteoroids entering the Earth[U+05F3]s atmosphere as objects surrounded by non-magnetized plasma, and consider efficient numerical simulation of radar reflections from meteors in the time domain. Instead of the widely used finite difference time domain method (FDTD), we use more generalized finite differences by applying the discrete exterior calculus (DEC) and non-uniform leapfrog-style time discretization. The computational domain is presented by convex polyhedral elements. The convergence of the time integration is accelerated by the exact controllability method. The numerical experiments show that our code is efficiently parallelized. The DEC approach is compared to the volume …

010504 meteorology & atmospheric sciencesComputer scienceMETEORPLASMATIC OBJECTSRADAR REFLECTIONS01 natural sciencesplasmatic objectslaw.inventionINTEGRAL EQUATIONSlawRadar010303 astronomy & astrophysicsSpectroscopyEARTH ATMOSPHEREvolume integral equationRadiationPLASMANUMERICAL MODELSMathematical analysisFinite differenceNUMERICAL METHODMETEORSAtomic and Molecular Physics and OpticsCALCULATIONSControllabilityDISCRETE EXTERIOR CALCULUSAstrophysics::Earth and Planetary AstrophysicsMAGNETOPLASMADiscretizationRADAR REFLECTIONTIME DOMAIN ANALYSISVOLUME INTEGRAL EQUATIONdiscrete exterior calculusELECTROMAGNETIC SCATTERINGOpticsFINITE DIFFERENCE TIME DOMAIN METHOD0103 physical sciencesSCATTERINGTime domainmeteorsNUMERICAL METHODS0105 earth and related environmental sciencesta113ta114Computer simulationbusiness.industryta111Finite-difference time-domain methodRADARDiscrete exterior calculuselectromagnetic scatteringradar reflectionsELECTROMAGNETIC METHODmeteoritbusinessJournal of Quantitative Spectroscopy and Radiative Transfer
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FDTD simulation for electromagnetic radiated emissions in 42 V vehicle electrical systems

2005

In this paper a full 3D approach, based on finite difference time domain method, is used to predict the electromagnetic radiated emissions from 42 V vehicle electrical loads. An experimental set-up has been arranged on purpose. A comparative analysis among measured and computed results is performed. The good agreement obtained among simulated and measured data enables to validate the numerical scheme. The proposed methodology contributes to predict electromagnetic emissions in the automotive environment since the design stage. Moreover, the proposed numerical tool can be used to define, for new vehicle electrical architectures, low cost test methods for electromagnetic compatibility and sui…

EngineeringDesign stagebusiness.industryFDTDAutomotive industryElectromagnetic compatibilityFinite-difference time-domain methodTransmission-line matrix methodComputer simulationElectric vehicleElectromagnetic wave emissionAutomotive engineeringAutomotive electronicsAutomotive engineeringFinite difference time domain analysisSettore ING-IND/31 - ElettrotecnicaElectrical engineeringTime domain analysiElectronic engineeringComputational electromagneticselectromagnetic radiated emissionbusinessvehicular electrical systemElectric load
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Transient response of a TLP-type floating offshore wind turbine under tendon failure conditions

2021

Abstract Among various types of floating offshore wind turbines (FOWTs), the tension leg platform (TLP) floating wind turbines have relatively small motions due to stiff tendons. Similar to TLP applications in the offshore industry, tendon failure may lead to deteriorated stability and large transient responses, which should be considered as part of accidental limit state (ALS) checks at the design stage of the TLP FOWTs. This paper takes the WindStar TLP system as a representative and investigates the transient effects of one-tendon failure on the system responses. A coupled numerical model is first established using the aero-hydro-servo-elastic simulation tool FAST. Subsequent numerical s…

Environmental EngineeringFloating offshore wind turbine (FOWT)Computer scienceNacelleTime domain analysis020101 civil engineeringOcean Engineering02 engineering and technology01 natural sciencesTurbine010305 fluids & plasmas0201 civil engineeringTendon failureTransient response0103 physical sciencesLimit state designTransient responseTension-leg platformTension leg platform (TLP)Wind powerbusiness.industryStructural engineeringCoupled aero-hydro-elastic modelOffshore wind powerAccidental limit stateTransient (oscillation)business
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Interference Effects in Photodetachment of F- in a Strong Circularly Polarized Laser Pulse

2007

A numerical simulation of photodetachment of F{sup -} by a circularly polarized laser pulse has been accomplished by using a Keldysh-type approach. The numerical results are in agreement with measurements of photoelectron energy spectra recently reported in the literature. The features exhibited by the spectra are traced back to quantum interference effects, in the same spirit as in a double-slit experiment in the time doma0008.

PhysicsComputer simulationComputer simulation Laser pulses Measurement theory Numerical methods Time domain analysisNumerical analysisInterference (wave propagation)LaserAtomic and Molecular Physics and OpticsSpectral lineSettore FIS/03 - Fisica Della MateriaPulse (physics)law.inventionX-ray photoelectron spectroscopylawPhysics::Atomic PhysicsAtomic physicsEnergy (signal processing)
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