...S. Corasaniti; P. Coppa; M. Potenza; G. Bovesecchi Four probes for measuring thermal conductivity, thermal diffusivity, and convection heat transfer coefficient were designed, built, and tested. In two of these probes (SP-1 and SP-2), three thermocouples were placed at 25%, 50%, and 75...

...M. Potenza; P. Coppa; S. Corasaniti; G. Bovesecchi The laser-flash method (LFM) is a technique commonly used to measure thermal diffusivity of homogeneous and isotropic materials, but can also be applied to macroscopically inhomogeneous materials, such as composites. When composites present thermal...

... circular heat source CHS composite Hankel Laplace thermal conductivity thermal diffusivity The problem of a three-dimensional (3D) heat flow from a finite circular heat source (CHS) has been of interest for many decades due to practical cases such as frictional heating, heating of electric...

... precision 150 0.035 4.04 Temperature phasing accuracy (ms) 6.67 0.003 0.03 Total diffusivity uncertainty (%) — — 6.6 A thermal radiation chamber has been developed for the nondestructive determination of thin coating thermal diffusivity. The device and methodology are initially...

... thermal conductivity is high for a given TBC architecture. The substrate effect with respect to thermal diffusivity is not as pronounced as the effect of thermal conductivity even though the trends are similar. High relaxation times of the substrate, as Fig. 12 indicates, have very little effect...

... displacement and the relative increase of thermal diffusivity are expressed in reduced algebraic form. Also presented are design formulas defining the specific driving power and the specific number of required tubes. Concerning the effective thermal diffusivity, the author’s predictions are fairly well...

... for the effective thermal relaxation time are derived, while for a Neumann problem, only a heat capacity identity is found. In contrast in the short time regime, under both Dirichlet and Neumann conditions, an expression that involves the effective thermal diffusivity and relaxation time as a function of the time...

... that high thermal conductivity contrast between film and substrate is essential for making accurate measurements. Parker , W. J. , Jenkins , R. J. , Abbott , G. L. , and Butler , C. P. , 1961 , “ Flash Method of Determining Thermal Diffusivity, Heat Capacity, and Thermal...

...Peter Vadasz The Kirchhoff transformation is the classical method of solution to the nonlinear thermal diffusion problem with temperature dependent properties. It essentially converts the nonlinear problem into a linear one if the thermal diffusivity is approximately constant. Unfortunately...

... to Darcy’s law employed to model the porous-medium resistance. Local thermal equilibrium does not hold due to the large difference in thermal diffusivity between the metal foam and the PCM. Therefore, a two-temperature approach is adopted, with the heat transfer between the metal foam and the PCM being...

...H. Sakamoto; F. A. Kulacki Transient heat transfer from an impulsively heated vertical constant heat flux plate embedded in a stationary saturated porous medium is studied experimentally and analytically to determine near-wall thermal diffusivity. The effective diffusivity is shown to depend...

... of the bubbles is modeled by increasing the fluid momentum and thermal diffusivities by an enhancement factor. The results show that the CML has been able to model flow boiling in a realistic manner. 05 02 2006 27 03 2007 boiling convection diffusion laminar flow laminar to turbulent...

... [Atomization and Sprays, 16 (6), pp. 907–932]. This finite conductivity model is based on the two-temperature film theory in which the turbulence characteristics of the droplet are used to estimate the effective thermal diffusivity for the liquid-side film thickness. Both one-way and two-way coupled...

...Jean-Luc Battaglia; Andrzej Kusiak; Jean-Christophe Batsale The aim of this work is to provide an analytical expression for the thermal diffusivity of a material in the configuration of the picosecond photoreflectance experiment. It is shown that the thermal diffusivity can be estimated from...

... aluminium molybdenum compounds nanoparticles explosives combustion Monte Carlo methods extinction coefficients thermal conductivity thermal diffusivity heat radiation thermo-optical effects 15 06 2005 28 06 2006 2007 American Society of Mechanical Engineers ...

... shrinkage drying thermal diffusivity thermal conductivity specific heat mass transfer temperature distribution partial differential equations convection least squares approximations food products inverse approach drying thermophysical properties heat and mass transfer coefficients...

... technique is unique because it avoids determining the effective thermal diffusivity and quantifying the boundary heat flux. The technique is used to measure the effective thermal conductivity of glass-water, glass-air, and steel-air systems. These systems yield solid-fluid conductivity ratios of 1.08, 25.7...

.... Kihm. 12 December 2003 21 September 2004 24 03 2005 chromium aluminium gold platinum metallic thin films thermoreflectance phonon spectra thermal conductivity thermal diffusivity Thermal management of micro- and optoelectronics is becoming more critical...

...-Forchheimer extension to the Darcy law to model the porous resistance. Owing to the difference in the thermal diffusivities between the metal foam and the PCM, local thermal equilibrium between the two is not assured. Assuming equilibrium melting at the pore scale, separate volume-averaged energy equations...

... are filled with air, phase change materials, or other fluids. Local thermal equilibrium between the solid filler and the matrix is not ensured in such systems since their thermal diffusivities are frequently very different. The use of a single volume-averaged energy equation for both the phases cannot...