A reexamination of energy accommodation experiments using the vibrating surface technique

Measurements of gas/surface energy accommodation using the vibrating surface method have been augmented by experiments which use an infrared sensing technique, rather than a thermocouple, to measure surface temperature. In contrast to previous results no surface temperature rises were detected that can be attributed to gas/surface energy accomodation. A numerical model was developed to simulate the energy flow near the surface of a solid oscillating in a rarified gas. The numerical simulation includes energy exchange between the gas and surface, radiative exchange between the surface and the chamber, and conduction into the solid. Conduction of energy into the solid dominates the surface thermal balance and damps the surface temperature rise due to gas/surface energy exchange to microdegree levels, well below the sensitivity of conventional temperature sensing techniques. Differences between our data and previously reported results are discussed.