The characteristics of thermocapillary flow and hydrothermal wave (HTW) in a shallow annular pool of silicone oil, heated from outer wall and cooled at inner wall, are investigated by numerical simulation. Several types of hydrolhermal waves occur under different temperature differences (△T). The critical temperature difference (△T_(cr)) for incipience of HTW is 8.14K in non-rotating pool. The wave number and oscillation frequencies decrease with increasing △T, except for cases near △T_(cr). At higher △T, such as 25K, there appears a new type of pattern: pulsating dotted patterns expanding outward. In slowly rotating pool, one group of HTW is stimulated from the beginning: rotation tends to "'rectify the rotation direction" of initial waves. Although, there are two possible traveling directions of HTW in the rotating pool, I.e., co-rotating and counter-rotating in respect to the pool rotation. The trajectories of fluid elements show flow characteristics clearly. The trajectories indicate the fluid elements do not exhibit significant azimuthal displacements, although the HTW patterns are constantly traveling in the azimuthal direction. Both HTW patterns and trajectories indicate that the pool rotation tends to suppress the HTW. On the inner wall, the higher Nu appears at the liquid surface while the maximum Nu appears near the mid plane on the outer wall. Its spatial variations (δNu) present wave patterns and propagate in the azimuthal direction corresponding to the traveling of HTW. The δNu becomes smaller especially on the inner wall by the pool rotation.
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