scholarly journals Accurate measurement of in-plane thermal conductivity of layered materials without metal film transducer using frequency domain thermoreflectance

2020 ◽  
Vol 91 (6) ◽  
pp. 064903 ◽  
Author(s):  
Xin Qian ◽  
Zhiwei Ding ◽  
Jungwoo Shin ◽  
Aaron J. Schmidt ◽  
Gang Chen
Keyword(s):  
Thermal Conductivity ◽  
Frequency Domain ◽  
Metal Film ◽  
Layered Materials ◽  
Film Transducer

Non‐Contact Mass Density and Thermal Conductivity Measurements of Organic Thin Films Using Frequency–Domain Thermoreflectance

2021 ◽  
pp. 2101404
Author(s):  
Christopher Perez ◽  
Robert Knepper ◽  
Michael P. Marquez ◽  
Eric C. Forrest ◽  
Alexander S. Tappan ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Frequency Domain ◽  
Mass Density ◽  
Organic Thin Films ◽  
Conductivity Measurements ◽  
Contact Mass

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

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.

scholarly journals NUMERICAL SIMULATION OF TRI-LAYERED MATERIALS UNDER CONTACT LOAD

2021 ◽  
Vol 13 (3) ◽  
pp. 164-170
Author(s):  
Sergiu Spinu ◽  
◽  
Keyword(s):  
Contact Problem ◽  
Frequency Domain ◽  
Frictional Coefficient ◽  
Analytical Techniques ◽  
Contact Problems ◽  
Layered Materials ◽  
Boundary Element Methods ◽  
Contact Load ◽  
Wear Protection ◽  
Influence Coefficients

Various biomedical components, such as dental crowns and hip prostheses, data processing devices, and other numerous mechanical components that transmit load through a mechanical contact, may benefit from a tri-layer design. The coating may be optimized for wear protection and corrosion prevention, whereas the intermediate layer provides increased adhesion between the outer layer and the substrate, and confines the crack propagation. The solution to the contact problem involving tri-layered materials can be pursued numerically with the finite element or the boundary element methods, but semi-analytical techniques benefitting from the efficiency of the fast Fourier transform (FFT) technique have also been successfully applied. At the heart of the FFT-assisted approach lie the frequency response functions (FRFs), which are analytical solutions for fundamental problems of elasticity such as the Boussinesq and Cerruti problems, but expressed in the frequency domain. Considering recent efforts and results in application of FFT to convolution calculations in contact problems, the displacement arising in a tri-layer configuration is computed in the frequency domain, and the contact problem is subsequently solved in the space domain using a state-of-the-art algorithm based on the conjugate gradient method. The method relies on the FRFs derived in the literature for tri-layered materials, and the efficiency and accuracy of computations in the frequency domain is assured by using the Discrete Convolution Fast Fourier Technique (DCFFT) with influence coefficients derived from the FRFs. The computer program reproduces well-known results for bi-layered materials. Numerical simulations are performed for various configurations in which the elastic properties of the layers, as well as the frictional coefficient, are varied. By using the newly advanced simulation technique, design recommendations may be advanced for the optimal configuration of tri-layered materials under contact load.

Measuring Thermal Conductivity with Magnitude-Dependent Frequency–Domain Thermoreflectance Using Modulated CW Lasers

2018 ◽  
Vol 39 (12) ◽  
Author(s):  
Kirby B. Myers ◽  
Prudhvidhar R. Gaddam ◽  
Xinjian Ding ◽  
Vladimir Kochergin ◽  
Scott T. Huxtable ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Frequency Domain ◽  
Dependent Frequency

scholarly journals Broadband phonon mean free path contributions to thermal conductivity measured using frequency domain thermoreflectance

2013 ◽  
Vol 4 (1) ◽  
Author(s):  
Keith T. Regner ◽  
Daniel P. Sellan ◽  
Zonghui Su ◽  
Cristina H. Amon ◽  
Alan J.H. McGaughey ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Frequency Domain ◽  
Free Path ◽  
Mean Free Path
Sign in / Sign up

Export Citation Format

Share Document