Thermal-Conductivity and Thermal-Diffusivity Measurements of Nanofluids by 3ω Method and Mechanism Analysis of Heat Transport

ABSTRACTThe thermal diffusivity of Ge has been measured over a temperature range from 300° C to 1010° C which includes values for the melt. Specific heat has been measured from room temperature to 727° C. Thermal conductivity has been calculated over the same temperature range as the diffusivity measurements. These data are reported along with the best values from the literature for the other parameters which are required to calculate the temperature and convective fields for the growth of germanium by the Bridgman method. These parameters include the specific heat, the viscosity, the emissivity, and the density as a function of temperature.

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Development of a Backfill for Containment of High-Level Nuclear Waste

MRS Proceedings ◽

10.1557/proc-11-641 ◽

1981 ◽

Vol 11 ◽

Cited By ~ 2

Author(s):

Floyd N. Hodges ◽

Joseph H. Westsik ◽

Lane A. Bray

Keyword(s):

Thermal Conductivity ◽

Thermal Diffusivity ◽

Nuclear Waste ◽

Release Rate ◽

Sodium Bentonite ◽

Waste Package ◽

Diffusivity Measurements ◽

High Level Nuclear Waste ◽

High Level ◽

Host Rocks

ABSTRACTSodium and calcium bentonites, pressed to densities between 1.9 and 2.2 g/cm3, have hydraulic conductivities in the range of 10−11 to 10−13 cm/s. Batch sorption distribution ratios (Rd) indicate that Sr, Cs, and Am are strongly sorbed on bentonites and zeolites, that Np and U are moderately sorbed on bentonites and zeolites, and that Am, Np, U, I, and Tc are strongly sorbed on charcoal. Sorption results with basalt and tuff ground waters are similar; however, iodine in tuff ground water sorbs more strongly on bentonites Thermal diffusivity measurements for dry, compacted (p ∼ 2.1 g/cm3) sodium bentonite indicate that the thermal conductivity of a high density bentonite backfill should be roughly similar to that of silicate host rocks (basalt, granite, tuff). These results indicate that a bentonite backfill can significantly delay the first release of many radionuclides into the host rock and that by forming a diffusion barrier a bentonite backfill can significantly decrease the longterm release rate of radionuclides from the waste package.

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Thermal conductivity of fibre/phenolic resin composites. Part I: Thermal diffusivity measurements

Composites ◽

10.1016/0010-4361(88)90265-0 ◽

1988 ◽

Vol 19 (3) ◽

pp. 251

Keyword(s):

Thermal Conductivity ◽

Thermal Diffusivity ◽

Phenolic Resin ◽

Resin Composites ◽

Diffusivity Measurements

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Thermal Diffusivity Measurements on Elastomers

Rubber Chemistry and Technology ◽

10.5254/1.3540469 ◽

1974 ◽

Vol 47 (4) ◽

pp. 849-857 ◽

Cited By ~ 3

Author(s):

H. K. Frensdorff

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Thermal Diffusivity ◽

Measurement Method ◽

Volumetric Heat Capacity ◽

Raw Data ◽

Diffusivity Measurements ◽

Thermal Diffusivities ◽

Heating Up ◽

Rubber Article

Abstract Thermal diffusivity, rather than thermal conductivity, is the property which governs rates of heating up and cooling down of a rubber article in the mold. It is preferable to measure it directly, rather than to derive it from separate measurements of thermal conductivity and volumetric heat capacity. A straightforward measurement method is described together with procedures for deriving the required results from the raw data. The sources of error are discussed, and ways for minimizing them are suggested. Thermal diffusivities for gum and black EPDM and fluoroelastomer are reported for temperatures from 0° to 100° C.

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