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Bubble dynamics is quite complicated in the field of two-phase hydrodynamics because the interfacial heat and mass transfer is comprehensively affected by various influencing factors. Bubble condensation can be either thermally controlled or inertia controlled. Inertia controlled bubble condensation indicates that considerable pressure difference exists between the steam bubble and ambient liquid. In this paper, the inertia controlled steam bubble condensation was simulated using moving particle semi-implicit (MPS) method. The spherical bubble is located in the center of the cylindrical pool which makes the possibility of 2-D axisymmetric computation. The lateral and bottom wall are set to be rigid insulated boundaries and the top is free surface boundary. The pool volume must be large enough to eliminate the effects by pool wall. The initial bubble pressure ranges from 0.48 MPa to 3.98 MPa, and the initial bubble diameter ranges from 2 mm to 5 mm, and the ambient water pressure and temperature is 0.1 MPa and 70 °C, respectively. The bubble dynamics during condensation was investigated and the influences of initial bubble pressure and diameter were obtained. The bubble deformation during condensation is shown in figure 1, and the variations of bubble diameters and pressures during condensation are shown in figures 2 and 3, respectively. [ABSTRACT FROM AUTHOR]

In present study, single steam bubble condensation in subcooled water have been simulated by using Moving Particle Semi-implicit(MPS) method. The liquid phase was described using moving particles and the two phase interface was set to be movable boundary which can be easily traced according to the motion of interfacial particles. The transient bubble deformation behaviors have been obtained and the results showed that both initial bubble size and subcooled degree influence bubble deformation behaviors greatly. Larger bubble experiences more severe deformation at lower liquid subcooled degree while bubble keeps near sphericity at higher liquid subcooled degree. All transient shape sequences can be found and explained properly in Grace’s graphic correlation. This work exhibits some fundamental characteristics of bubble condensation using MPS-MAFL which is expected to be further adopted to evaluate other complicated bubble dynamics problems. [ABSTRACT FROM AUTHOR]