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Gas phase pressure effects on the apparent thermal conductivity of jsc-1a lunar regolith simulant
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Yuan, Zeng-Guang Kleinhenz, Julie E. |
| Copyright Year | 2011 |
| Description | Gas phase pressure effects on the apparent thermal conductivity of a JSC-1A/air mixture have been experimentally investigated under steady state thermal conditions from 10 kPa to 100 kPa. The result showed that apparent thermal conductivity of the JSC-1A/air mixture decreased when pressure was lowered to 80 kPa. At 10 kPa, the conductivity decreased to 0.145 W/m/degree C, which is significantly lower than 0.196 W/m/degree C at 100 kPa. This finding is consistent with the results of previous researchers. The reduction of the apparent thermal conductivity at low pressures is ascribed to the Knudsen effect. Since the characteristic length of the void space in bulk JSC-1A varies over a wide range, both the Knudsen regime and continuum regime can coexist in the pore space. The volume ratio of the two regimes varies with pressure. Thus, as gas pressure decreases, the gas volume controlled by Knudsen regime increases. Under Knudsen regime the resistance to the heat flow is higher than that in the continuum regime, resulting in the observed pressure dependency of the apparent thermal conductivity. |
| File Size | 169605 |
| Page Count | 9 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20110015332 |
| Archival Resource Key | ark:/13960/t7tn26q3t |
| Language | English |
| Publisher Date | 2011-07-17 |
| Access Restriction | Open |
| Subject Keyword | Lunar And Planetary Science And Exploration Pressure Effects Selenology Low Pressure Thermal Conductivity In Situ Resource Utilization Gas Pressure Heat Transmission Regolith Lunar Rocks Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
