The Velocity, Pressure and Temperature Oscillations

The estimations enable us to disregard the minor convective effects, and to consider the problem in the framework of a pure conductive approximation. Neglecting, in Eq. (11.17), the term andM,- we reduce the problem to 

First we restricted ourselves to considering a particular case of flow in a capillary tube with q j = const. ((/ = 0). We also neglected the change of the capillary pressure through the changes of the contact angle, due to the motion of the meniscus. Accordingly we assume that / = 0 in condition (11.25). 

the velocity oscillations, in the flow of an incompressible fluid, depend only on time, i.e., the liquid and vapor columns move in the capillary tube, on the whole, similar to a solid body. Bearing this in mind, we present the solution of Eq. (11.15) as follows  

The specific friction force Fi in laminar flow is expressed as (Yarin et al. 2002) 

Taking into account Eqs. (11.42) and (11.44) we can present the pressure oscillations as follows  

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The solution of Eqs. (11.15-11.17), subject to the conditions (11.24-11.26), determines the displacement of the interface in time, as well as the evolution of the velocity, pressure and temperature oscillations. 

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