Photoacoustic Measurements to Determine Thermal Diffusivities of Gases at Moderate Pressures

Abstract High poloidal beta scenarios with favorable energy confinement (β_p~1.9, H_98y2~1.4) have been achieved on Experimental Advanced Superconducting Tokamak (EAST) using only radio frequency waves heating. Gyrokinetic simulations are carried out with experimental plasma parameters and tokamak equilibrium data of a typical high β_p discharge by the GTC code. Linear simulations show that electron temperature scale length and electron density scale length destabilize the turbulence, collision effects stabilize the turbulence, and the instability propagates in the electron diamagnetic direction. These indicate that the dominant instability in the core of high β_p plasma is collisionless trapped electron mode. Ion thermal diffusivities calculated by nonlinear gyrokinetic simulations are consistent with the experimental value, in which the electron collision effects play an important role. Further analyses show that instabilities with k_θ ρ_s>0.38 are suppressed by collision effects and collision effects reduce the radial correlation length of turbulence, resulting in the suppression of the turbulence.

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Thermal diffusivities of thin diamond films on silicon

Diamond and Related Materials ◽

10.1016/0925-9635(93)90167-z ◽

1993 ◽

Vol 2 (8) ◽

pp. 1185-1190 ◽

Cited By ~ 25

Author(s):

O.W. Käding ◽

E. Matthias ◽

R. Zachai ◽

H.-J. Füßer ◽

P. Münzinger

Keyword(s):

Diamond Films ◽

Thermal Diffusivities

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3006 Measurement of Thermal Diffusivities and Conductivities of Several Meterials(Environmental Engineering)

Transactions of the Architectural Institute of Japan Summaries of Technical Papers ◽

10.3130/aijsaxxe.42.0_490 ◽

1967 ◽

Vol 42 (0) ◽

pp. 490

Author(s):

Shumpei Ohara

Keyword(s):

Environmental Engineering ◽

Thermal Diffusivities

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Thermal Diffusivities and Influence of Cooking Temperature Combined With Sodium Lactate Addition on Microbiological Characteristics of Rabbit Ham

Advance Journal of Food Science and Technology ◽

10.19026/ajfst.7.1302 ◽

2015 ◽

Vol 7 (4) ◽

pp. 242-249 ◽

Cited By ~ 2

Author(s):

Blanco-Lizarazo Blanco-Lizarazo ◽

Carla Maria ◽

Llorente-Bousquets Adriana ◽

Lopez-Franco Lopez-Franco ◽

Maria Guadalupe ◽

...

Keyword(s):

Sodium Lactate ◽

Microbiological Characteristics ◽

Cooking Temperature ◽

Thermal Diffusivities

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Thermal Diffusivity of Copper/Linear-low-density Polyethylene Composites

Polymers and Polymer Composites ◽

10.1177/096739111702500603 ◽

2017 ◽

Vol 25 (6) ◽

pp. 447-452

Author(s):

James K. Carson ◽

Mohamed Alsowailem

Keyword(s):

Thermal Conductivity ◽

Thermal Diffusivity ◽

High Density Polyethylene ◽

Relative Increase ◽

Low Density Polyethylene ◽

Low Density ◽

Linear Low Density Polyethylene ◽

Capacity Data ◽

Thermal Diffusivities ◽

Polyethylene Composites

The thermal diffusivities of copper/linear-low-density polyethylene (Cu/LLDPE) composites were measured relative to the thermal diffusivity of pure LLDPE. The relative thermal diffusivities were similar to those obtained for copper/high-density polyethylene composites, but were noticeably different from estimated values derived from thermal conductivity, density and specific heat capacity data for Cu/LLDPE from the literature. The thermal diffusivity of the composite material initially decreased below that of the pure polymer with the addition of a small amount of copper, before increasing above it as more was added. There would appear to be marginal or no benefit from adding less than about 15 to 20% metal by volume to a polymer, since the relative increase in thermal diffusivity only becomes significant for greater volumes.

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The Small-Péclet-Number Approximation for Radiative Zones and its Application to Shear Layer Instabilities

Symposium - International Astronomical Union ◽

10.1017/s0074180900195853 ◽

2004 ◽

Vol 215 ◽

pp. 346-347

Author(s):

F. Lignières

Keyword(s):

Asymptotic Behavior ◽

Thermal Diffusivity ◽

Asymptotic Analysis ◽

Shear Layer ◽

Peclet Number ◽

Earth Atmosphere ◽

Hydrodynamic Equations ◽

The Earth ◽

Shear Instabilities ◽

Thermal Diffusivities

Thermal diffusivities within stars are higher by several orders of magnitude than in the earth atmosphere. This particularity of the stellar fluid has subtle effects on the dynamics of stably stratified radiative zones as it contributes to favour some flows and supress others. An asymptotic analysis of hydrodynamic equations for large values of the thermal diffusivity is presented and this results in a simplification of the dynamical effects of the thermal diffusivity. This asymptotic behavior proved to be very useful to understand shear instabilities of Kelvin-Helmholtz type.

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