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Heat transfer from cylinder in symmetrical chamber resembling Pirani type pressure gauge studied for dependence on pressure, size and temperature of cylinder, and molecular weight of gas
Conventional thermal conductivity gauges (e.g. Pirani gauges) lend themselves to applications such as leak detectors, or in gas chromatographs for identifying various gas species. However, these conventional gauges are physically large, operate at high power, and have a slow response time. A single-walled carbon-nanotube (SWNT)-based chemical sensing gauge relies on differences in thermal conductance of the respective gases surrounding the CNT as it is voltage-biased, as a means for chemical identification. Such a sensor provides benefits of significantly reduced size and compactness, fast response time, low-power operation, and inexpensive manufacturing since it can be batch-fabricated using Si integrated-circuit (IC) process technology.
Performance of ion rocket thrust augmentor, Langmuir probe measurements, secondary electron emission from porous tungsten, and heat transfer from large diameter Pirani pressure gauges