Acoustic wave prediction in flowing steam-water two-phase mixture

The transient two-fluid model has been used to develop a general relation f or acoustic waves with steam-water two-phase mixture in one-dimensional flo wing system. The analysis is valid in principle over the whole void fractio n region. Both the mechanical and thermal nonequilibrium are considered. Th e vapor-liquid interface heat flux is derived from the one dimensional Four ier heat conduction equation to evaluate the interphase evaporation or cond ensation rate. Calculations are performed for pressures from 0.07 to 16.0 M Pa, void fractions from 0.0 to 1.0. Higher frequency limit of sonic velocit ies are only relied on the pressures and void fractions, and are insensitiv e to the bubble radius, tube diameter, and the velocity difference between the two phases. The predicted sonic velocities are compared with some exper imental data for low pressures. Good agreement has been achieved between th e predictions and the experimental data. (C) 2000 Elsevier Science Ltd. All rights reserved.