Dynamic simulation of heat conduction using a BEM model in the frequency domain: an experimental validation

Abstract Using forward and inverse dynamic analysis, the dynamic simulation of a backhoe has been compared with experiments. In the experiment, recorded were the configuration and force histories; that is, velocity and position, and force output from the hydraulic cylinder-all were measured in the time domain. When the experimental force history is used as driving force in the simulation, forward dynamic analysis produces a corresponding motion history. And when the experimental motion history is used as if a prescribed trajectory, inverse dynamic analysis generates a corresponding force history. Therefore, these two sets of motion and force histories — one set from experiment, and the other from the simulation that is driven forward and backward with the experimental data — are compared in the time domain. The comparisons are discussed in regard to the effects of variations in initial conditions, friction, and viscous damping.

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Atomistic Dynamic Simulation of Transport Processes in Polymer Electrolyte Fuel Cell and Experimental Validation

ECS Meeting Abstracts ◽

10.1149/ma2005-02/26/992 ◽

2005 ◽

Keyword(s):

Fuel Cell ◽

Polymer Electrolyte ◽

Dynamic Simulation ◽

Experimental Validation ◽

Transport Processes ◽

Polymer Electrolyte Fuel Cell

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Assessment of Models for Extracting Thermal Conductivity From Frequency Domain Thermoreflectance Experiments

ASME 2020 Heat Transfer Summer Conference ◽

10.1115/ht2020-8920 ◽

2020 ◽

Author(s):

Siddharth Saurav ◽

Sandip Mazumder

Keyword(s):

Thermal Conductivity ◽

Heat Conduction ◽

Boundary Conditions ◽

Frequency Domain ◽

Heat Conduction Equation ◽

Conduction Equation ◽

Hyperbolic Heat Conduction ◽

Phase Lag ◽

Computational Domain ◽

Fourier Heat Conduction

Abstract The Fourier heat conduction and the hyperbolic heat conduction equations were solved numerically to simulate a frequency-domain thermoreflectance (FDTR) experimental setup. Numerical solutions enable use of realistic boundary conditions, such as convective cooling from the various surfaces of the substrate and transducer. The equations were solved in time domain and the phase lag between the temperature at the center of the transducer and the modulated pump laser signal were computed for a modulation frequency range of 200 kHz to 200 MHz. It was found that the numerical predictions fit the experimentally measured phase lag better than analytical frequency-domain solutions of the Fourier heat equation based on Hankel transforms. The effects of boundary conditions were investigated and it was found that if the substrate (computational domain) is sufficiently large, the far-field boundary conditions have no effect on the computed phase lag. The interface conductance between the transducer and the substrate was also treated as a parameter, and was found to have some effect on the predicted thermal conductivity, but only in certain regimes. The hyperbolic heat conduction equation yielded identical results as the Fourier heat conduction equation for the particular case studied. The thermal conductivity value (best fit) for the silicon substrate considered in this study was found to be 108 W/m/K, which is slightly different from previously reported values for the same experimental data.

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