Summary
In the present paper we consider sound propagation in rarefied monoatomic gases from the point of view of a previously proposed modified Navier-Stokes equation. The agreement between theory and experiment is rather good for sound dispersion and absorption in the region where the ratio between the mean free path and the wavelength lies within the limits 0.1 and 1. We also discuss the asymptotic behaviour for high-frequency values of the sound dispersion and absorption and suggest that further measurements in the Knudsen regime of sound dispersion (neglecting absorption) would be useful to test the Validity of sound wave as well as free-molecule propagation theory.
Riassunto
In questo lavoro, facendo riferimento ad una equazione modificata di Navier-Stokes proposta precedentemente, si prende in esame la propagazione del suono nei gas monoatomici rarefatti. La dispersione e l’assorbimento calcolati sono in buon accordo con i risultati sperimentali in tutta la regione in cui il rapporte tra libero cammino medio e lunghezza d’onda varia tra 0.1 e 1. Si discute anche il comportamento asintotico della dispersione e dell’assorbimento per alti valori della frequenza e si rileva l’opportunità di ulteriori misure della dispersione (trascurando l’assorbimento) nel regime di Knudsen al fine di accertare se la propagazione del suono avviene mediante moto ondoso o tramite un flusso di molecole libere.
Similar content being viewed by others
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Carrassi, M., Morro, A. Some remarks about dispersion and absorption of sound in monoatomic rarefied gases. Nuov Cim B 13, 281–299 (1973). https://doi.org/10.1007/BF02726711
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF02726711