过冷水撞击低温基底结冰是典型的动态过程，易形成气泡孔隙，这一孔隙结构是决定动态结冰热/力学特性的根本因素。针对动态结冰微观孔隙结构定量研究的不足，以风洞结冰显微图像为对象，采用前期提出的变分分割模型，建立了结冰图像孔隙提取方法；基于孔隙提取结果，系统分析不同结冰条件下的孔隙形态、孔径分布等相关结构特征，提出了孔隙类球形、孔径分布连续的结论，并建立了孔隙孔径分布函数，推导了其概率密度函数。结果表明，变分图像分割方法作为孔隙提取的手段具有适用性和优越性，所提孔隙结构相关定量结果与试验数据具有较高的吻合度，基于此开展动态结冰微观结构定量研究是可行的。
When super-cooled water droplets impinge a substrate, ice with air pores is formed dynamically. The porou structure is the main factor which influences the thermal and mechanical characteristics of ice. To give a quantitative study of the porous structure of dynamic ice, a pore extraction method is developed based on a variational segmentation model proposed earlier. The method is used to extract the micro image of the ice formed in the ice wind tunnel. The shape, the diameter distribution and other characteristics of the ice formed under different conditions are analyzed systematically. Quantitative study shows that the pore in the ice is sphere-like, and the diameter value is of continuous attribute. The probability density function for the pore diameter is deduced based on the distribution function of the pore diameter. It is clear that the variational segmentation model is feasible and advantageous for pore extraction. The quantitative results are highly consistent with experiment results, and the corresponding quantitative research on the micro-porous structure of dynamic ice can be carried out based on the method proposed.
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