The hysteresis phenomena of flow patterns due to thermal and solutal marangoni convections in a liquid bridgeunder zero gravity

摘要

The hysteresis phenomenon of flow patterns due to thermal and solutal Marangonisconvection in a liquid bridge under zero gravity was numerically simulated. A threedimensional half-zone configuration of the Floating Zone (FZ), formed between hotand cold discs, was considered. The field equations; continuity, momentum, energy,and mass transport equations, were solved numerically by the PISO algorithm, andthe open source software OpenFOAM was used. Three sets of initial conditions wereused. The first is the conditions of no-flow and constant solutal Marangoni numbers,the other two are the gradually increasing or decreasing solutal Marangoni numbers.Results showed that the flow becomes 3-D unstable at a larger solutal Marangoninumber than the critical number (MaC)cr, and the (MaC)cr depends on the initialcondition. The flow structure clearly shows hysteresis behavior of the flow field withabout 24 % difference between the critical values in the hysteresis diagram.