# Accession Number:

## AD0411443

# Title:

## SOME REMARKS ON THE VELOCITY OF SOUND FOR TWO-PHASE MIXTURES AND FLOWS,

# Descriptive Note:

# Corporate Author:

## MASSACHUSETTS INST OF TECH CAMBRIDGE ENGINEERING PROJECTS LAB

# Personal Author(s):

# Report Date:

## 1963-04-01

# Pagination or Media Count:

## 60.0

# Abstract:

Expressions were derived for the isentropic velocity of sound for single-component vapor liquid and two-component gas-liquid two-phase mixtures. Extremely low minimum values for the velocity of sound are predicted for single-com ponent mixtures near the saturated liquid states and for two-component mixtures when the gas volume and liquid volume are about equal. Al hough the isothermal velocity of sound may be more appropriate for the mixtures, it has been shown that the ratio of the isentropic and isothermal velocities will be close to unity for most cases of interest. The effect of liquid compressibility on the calculated results has also been studied and found to be small. The existence of a slip velocity between the phases does not change the minimum velocity appreciably although the mixture composition at which the minimum occurs does change. Since the minimum values of the velocity of sound may be less than 100 ftsec and since many two-phase mixtures are transported in this velocity range, engineering considerations of two-phase flow problems must include many compressibility effects normally encountered in the field of gas dynamics at much higher velocities. For many two-phase flow situ ations, high subsonic and supersonic Mach numbers will be produced at relatively low flow veloci ties. The engineering design of two-phase flow systems may involve choking phenomena, the design of convergent-divergent nozzles, and the possi bility of shock wave formation. Author