The accreted ice on the exposed surface is well known to result in severe accidents to power transmission lines, aircraft, boats, and so on, and cause the significant economic losses. The refrigeration equipment of the agricultural by-products is no exception. With the rapid development of the refrigeration industry and the improvement of the food requirement, the number of the China's refrigeration equipment to store the agricultural by-products increases gradually every year. The problem of the influence of the ice accumulation on the refrigeration equipment has become outstanding gradually. In order to reduce the harm and the economic losses of storage of agricultural by-products caused by the icing adhesion phenomenon, an active de-icing model was designed according to the volume expansion during the freezing process. The de-icing model adopted the swelling force as the active power to destroy the stability of the contact interface between the ice and the substrate surface. During the experiment, ternary quadratic regression orthogonal experiment method was adopted to design the experiment conditions, like the range of the solution mass concentration and the size of the pits, and the mathematic model was set up to analyze the relationship between the experimental factors and the ice adhesion strength. The test used the 6061 aluminum alloy whose size is 60 mm × 60 mm × 6 mm as the sample material and took the laser processing or milling to fabricate the different sizes of pits. And the pits were full of different mass concentrations of ethanol solution. The sample surface was covered by the biaxially oriented polypropylene (the abbreviation is BOPP). The experimental results showed that the de-icing model significantly reduced the ice adhesion strength, and the different pit sizes and mass concentrations of filled ethanol solution had different effects on reducing the ice adhesion strength. When the pit diameter was 23.172 mm, the depth was 4.349 mm, and the pit was filled with 8.05% ethanol solution, the reduction rate of ice adhesion strength by the model was 92.72%. The regression analysis method was used to solve the regression equation. And the order of the influence of different experiment factors on decreasing ice adhesion strength was determined, which was pit depth, mass concentration of ethanol solution and pit diameter from high to low. The mechanism of the de-icing model was analyzed through the adopted regression equation. The paper considered that the freezing of solution in the pits would release the expansion energy in a short time and directly act on the freezing interface due to both rigid sides of the pit. The ethanol solution would contain more and more phase transformation energy with the increasing of the pit depth. The higher the energy density acting on the BOPP film, the greater the damage to the stability of the contact interface, the greater the ice adhesion strength decreased. When the mass concentration of ethanol solution in the pits was reduced, it would generate more expansion energy. That meant that the elastic film would bear more expansion force under the same conditions and it would increase the reduction rate of the ice adhesion strength. However, the decrease rate of the ice adhesion strength would not increase as the radius of the pit increasing. As the radius increased, the area of the expansion load acting on the contact interface would increase in square. Therefore, it decreased the power density on the BOPP film and the reduction rate would be reduced. The study takes the phase expansion force to improve the surface active characteristics of the refrigeration equipment and provides the experimental basis for developing the active de-icing method and a new thought for de-icing methods.%农产品冷藏设备换热表面上的结冰堆积造成能源消耗,并影响了农产品的储藏品质.该文基于水结冰相变过程中的膨胀应力及不同冰点的溶液相变时差对结冰界面稳定性的影响现象,采用带有不同尺寸的凹坑且表面粘附双向拉伸聚丙烯薄膜(biaxially oriented polypropylene,BOPP)的6061铝合金为冻粘基体,探究凹坑直径、凹坑深度及凹坑内的不同质量分数的乙醇溶液对结冰附着强度的影响规律.对试验结果进行方差分析,建立了评价指标与各影响因素的数学回归模型,确定防结冰表面对结冰附着强度影响的主次顺序为凹坑深度、乙醇溶液质量分数、凹坑直径,结合响应面分析得到对结冰附着强降低率具有显著作用的工艺参数组合为:质量分数为8.05%的乙醇溶液和直径23.172 mm、深度4.349 mm的凹坑时,表面结冰附着强度的降低率达到了92.72%.利用水冻结成冰的过程中,释放的冻结膨胀能,破坏冰与材料之间接触界面的稳定性,降低了结冰附着强度,提高冷藏设备表面的主动除冰特性,为后期基于相变膨胀进行防除冰方法的开发提供新思路及试验依据.
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