Determination of the effective thermal conductivity of granular materials under varying pressure conditions

Details Determination of the effective thermal conductivity of granular materials under varying pressure conditions Determination of the effective thermal conductivity of granular materials under varying pressure conditions

Dec 2008

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008jgre..11312004h&link_type=abstract

Journal of Geophysical Research, Volume 113, Issue E12, CiteID E12004

Physics

8

Physical Properties Of Rocks: Thermal Properties, Planetary Sciences: Solar System Objects: Moon (1221), Planetary Sciences: Solid Surface Planets: Surface Materials And Properties, Planetary Sciences: Solid Surface Planets: Instruments And Techniques

Scientific paper

We report on thermal conductivity measurements performed on glass spheres of different grain sizes under varying pressure conditions ranging from 10-5 up to 1000 hPa. Glass spheres of 0.1 up to 4.3 mm were used as an analogue for the coarse-grained fractions of planetary regolith. From the obtained conductivity versus pressure data, sample pore sizes were derived and compared to estimated pore sizes. An increasing difference between derived and estimated pore size with increasing grain size was found. The behavior of the granular matter with decreasing pressure was analyzed by estimating the Knudsen number for the given system. The results indicate a high variability of the effective thermal conductivity for Martian conditions. Furthermore, the results imply that the thermal conductivity reaches a grain size-dependent, but pressure-independent, value for pressures below 0.01 hPa. For vacuum conditions a linear relation between grain size and effective thermal conductivity was found. Additionally, a mixture was analyzed, which showed a stronger decrease with gas pressure compared to the single-sized samples. From the pore size derived for the mixture an ``effective'' grain size composed of weighted mean of the mixture components was determined.

Affiliated with

Also associated with

No associations

Rating

Determination of the effective thermal conductivity of granular materials under varying pressure conditions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Determination of the effective thermal conductivity of granular materials under varying pressure conditions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Determination of the effective thermal conductivity of granular materials under varying pressure conditions will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-969258