Acoustic sensors for analyzing binary gas mixtures

This paper concerns the development of robust, directly acting, acoustic gas sensors, which can be used for analyzing two-component gas mixtures even under harsh measuring conditions, such as high temperatures up to 300degC; aggressive,explosive, or toxic pollutions in the gas mixture; dust; electromagnetic disturbances; nuclear radiation; or very fast concentration changes of the mixture components. These characteristics result from the predominantly mechanical structure of the sensors. An important application of the robust sensor is the in situ measurement of humidity in the hot and contaminated exhaust air of industrial driers