AVS 53rd International Symposium
    Vacuum Technology Tuesday Sessions
       Session VT-TuP

Paper VT-TuP8
Viscosity Measurement of Ozone-oxygen Gas Mixture with a Quartz-Friction Sensor

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Vacuum Technology Poster Session
Presenter: A. Kurokawa, AIST, Japan
Authors: A. Kurokawa, AIST, Japan
Y. Kobayashi, AIST, Japan
Correspondent: Click to Email
We would report on the viscosity of ozone-oxygen gas mixture. To measure the viscosity we developed a quartz-friction sensor method which was based on the principle that the resonance impedance of the vibrating crystal oscillator depends on the viscosity of the surrounding gas. This is an essential technique because the highly concentrated ozone gas is very reactive and easy to decompose by light absorption and heating. With the following procedure we evaluated the viscosity of the gas. The crystal oscillator was vibrated at its characteristic frequency which was around 32 kHz. The oscillator was set in the flow of ozone-oxygen gas mixture, and its impedance was monitored. During the measurement the gas pressure was measured by a capacitance manometer to cancel the pressure dependence of the impedance of the oscillator. We used the approximation that the variation of the impedance related to the viscosity of the gas. The impedance variation was defined with the impedance origin obtained at the vacuum pressure. The approximation curve was derived by the fitting to viscosity-known gases such as argon, nitrogen, oxygen, and consequently the measurement of impedance variation could give the viscosity. The highly-concentrated ozone gas was supplied from the ozone-gas generator in which 5 vol% ozone gas generated by electric discharge was condensed by selective absorption on cooled silica gel. All of the gas piping for ozone-gas had been electrochemically polished and well stabilized to minimize the decomposition of the ozone gas on the wall surface. Finally we derived the viscosity of the mixed gas with 20 vol% ozone in the 10 kPa to 100 kPa range of the gas pressure and that with 70 vol% in the 1 kPa to 10 kPa range.