A novel non-intrusive microcell for sound-speed measurements in liquids. Speed of sound and thermodynamic properties of 2-propanone at pressures up to 160 MPa

• Autor(a) principal: Azevedo, R. Gomes de
• Data de Publicação: 2004
• Outros Autores: Szydlowski, J., Pires, P. F., Esperança, J. M. S. S., Guedes, H. J. R., Rebelo, L. P. N.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.13/3914
• topic: Speed of sound; Density; Pressure effects; 2-Propanone; Acetone; .; Faculdade de Ciências Exatas e da Engenharia

A novel high-pressure, ultrasonic cell of extremely reduced internal dimensions ( 0.8 10 6 m3) and good precision for the determination of the speed of propagation of sound in liquids was conceived and built. It makes use of a non-intrusive methodology where the ultrasonic transducers are not in direct contact with the liquid sample under investigation. The new cell was used to carry out speed of sound measurements in 2-propanone (acetone) in broad ranges of temperature (265 < T =K < 340) and pressure (0:1 < p=MPa < 160). (p; q; T ) data for acetone were also determined but in a narrower T ; p range (298 to 333 K; 0.1 to 60 MPa). In this interval, several thermodynamic properties were thus calculated, such as: isentropic (js) and isothermal (jTÞ compressibility, isobaric thermal expansivity (ap), isobaric (cp) and isochoric (cv) specific heat capacity, and the thermal pressure coefficient (cv). Comparisons with values found in the literature generally show good agreement.