title: A phase comparison technique for sound velocity measurement in strongly dissipative liquids under pressure.
abstract: An accurate technique for the sound velocity measurement in strongly dissipative liquids is elaborated. This technique is based upon high sensitive phase detection. Each medium, at a given temperature and pressure, is characterized by a specific phase shift due to the propagation of the ultrasonic wave within the analyzed medium. By tuning the insonation frequency of the ultrasonic signal, a succession of consecutive nulls of the output dc voltage generated by the phase detector is observed. Thus from the obtained series of frequency values, the sound velocity is computed. Numerous organic liquids, such as alcohols and alkanes, have been used to validate this experimental procedure. As the developed method is well suited for the sound velocity measurement in strongly dissipative liquids, measurements of compressional wave velocity in heavy oil are also carried out over the temperature range 10 degrees C to 50 degrees C. The experimental results agree well with those found in the literature. The accuracy of the developed method is estimated at about +/-0.3%.
authors: Laboratoire des Fluides Complexes, UMR 5150, Universite de Pau et des Pays de l'Adour, BP 1155, 64013 Pau Cedex, France. hassinakhelladi@yahoo.fr
authors: Hassina
authors: H
authors: Khelladi
authors: Frédéric
authors: F
authors: Plantier
authors: Jean Luc
authors: JL
authors: Daridon
mesh_terms: D000438:Alcohols / Q000737:chemistry; D000473:Alkanes / Q000737:chemistry; D006801:Humans; D008962:Models, Theoretical; D009038:Motion; D009821:Oils / Q000737:chemistry; D011312:Pressure; D015203:Reproducibility of Results; D013016:Sound; D013696:Temperature; D013997:Time Factors; D014465:Ultrasonics
chemical_list: D000438:Alcohols; D000473:Alkanes; D009821:Oils