Surface tension effect on stability of two-phase stratified flow

In this paper, the effect of wavelength on the disturbed interface of a two-phase stratified regime will be discussed. It is assumed that the two phases are completely separated and are flowing parallel to each other along the duct. In order to analyze the stability of the two-phase stratified flow, a small disturbance is considered at the interface. Growth or decline of the interface disturbance, relative velocity and surface tension in time will be discussed analytically and numerically. Numerical analysis is applied using the finite difference method. The results of the numerical method are compared with the analytical results of prior investigators. The results of the present paper show that the non-linear conservation equations model discussed is capable of predicting two-phase stratified flow behavior. The surface tension increases the physics of the model and has a positive effect on the convergence of the numerical result of the two-phase flow model. The convergence of the numerical results was obtained and is presented in the results section of the paper. This conclusion is unique to this paper and the Ransom and Hicks model [Ransom, V.H., Hicks, D.L., 1984. Hyperbolic two-pressure models for two-phase flow. J. Comput. Phys. 53, 124-151].