本文从团聚(clustering)的分子动力学过程出发,研究微尺度沸腾相变的物理机制。通过分析沸腾系统势能变化趋势,指出核化阶段必然伴随团聚体积的增加,从而导致压力扰动的产生。在微尺度条件下,这种压力扰动将可能主导沸腾系统的相变行为。由此模型导出相变发生的临界尺度判据,在量级上与实验取得很好的一致 In this paper, based on the molecular dynamics of clustering, the physical mechanism of micro-scale boiling phase transition is studied. By analyzing the tendency of potential energy in boiling system, it is pointed out that nucleation stage inevitably accompanies the increase of agglomeration volume, which leads to the generation of pressure disturbance. Under micro-scale conditions, this pressure disturbance will likely dominate the phase transition behavior of the boiling system. From this model, the criterions of the critical scale of the phase transition are obtained and agree well with the experimental ones