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线性稳定性分析研究了环形池内反常热毛细对流及其稳定性,分析了液层深度对它们的影响.结果表明:当Ma较小时,反常热毛细对流为稳定的轴对称流动;当Ma超过临界值后,反常热毛细对流失稳,形成三维稳态波纹,波纹的形态与液层厚度有关,当液层深度H(H=d/ΔR,d为环形池深度,AR为内外径宽)小于0.0833时,失稳波纹为波数较多、位于环形池外环边沿、短小细密的“边沿波”;当H大于0.0833时,为波数较少、波纹较宽、几乎占据整个液层、呈轮辐状的“轮形波”;H等于0.0833时,同时存在这两种波纹的可能性.随着液层深度的增加,对流失稳的临界Ma数逐渐减小.能量收支分析讨论了它们的失稳机理.“,”Anomalous thermocapillary convection and its stability are investigated in annular pools by linear stability analysis,and the influence of liquid layer depths (H =d/AR=0.05～0.5) is investigated.The results reveal that when Ma is small,anomalous thermocapillary convection is a two-dimensional steady axisymmetric flow.When Ma exceeds a certain threshold value it is destabilized to be steady three-dimensional flow.As to the different liquid layer depths,two kinds of instability patterns can occur.In shallow pools (H＜0.0833),the instability patterns are short and thin “marginal patterns” with more wave numbers,located near the outer wall of the annular pools.In deep pools (H＞0.0833),the basic flow destabilizes into a wide spoke-like perturbation patterns with less wave number,occupying the whole liquid layer,called as “spoke patterns”.When H=0.0833,two kinds of wave patterns are possible with equal probability.With increasing the liquid layer depth,the critical Marangoni number decreases.Their instability mechanisms are explained by energy budgets analysis.