考虑液滴体积的接触角拟合算法  

Contact Angle Algorithm Considering Drop Volume

作　　者：徐志钮[1] 律方成[1] 丁傲[1] 李嫚[1] 金虎[1] 梁英[1] 李和明[1] 

机构地区：[1]华北电力大学生物质发电成套设备国家工程实验室,保定071003

出　　处：《高电压技术》2010年第6期1415-1422,共8页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724508)~~

摘　　要：当液滴体积较小时其边缘近似为圆形,基于圆方程进行拟合的算法有望准确获得接触角;当液滴体积增加时其边缘趋向于椭圆,此后基于椭圆方程进行拟合的算法有望能准确获得接触角。为了加快拟合速度,使用了一种直接计算获得椭圆参数的算法,避免了迭代且提高了计算效率。用圆拟合算法与椭圆拟合算法对不同接触角的圆和椭圆仿真图像进行计算,结果表明:当接触角较小时,无论是对圆图像还是对椭圆图像使用圆拟合算法都有较小的误差;当接触角较大时,如果是圆图像则两种算法都有较高精确度,如果是椭圆图像则基于椭圆的算法的误差更小。因此,接触角较小时使用基于圆的拟合算法,否则使用基于椭圆的算法。且针对不同的椭圆离心率给出了算法选择的临界接触角。对室温硫化(RTV)硅橡胶拍照所得水珠图像进行拟合,发现结果与仿真分析相近,且随着体积的增加液滴边缘的离心率增大,两种算法所得结果的差距也增大。If droplet volume is large,the edge of the droplet is approximate to ellipse,then the fitting method based on ellipse equation has high accuracy.For improving the calculation speed of fitting procedure,a direct least square algorithm for ellipse equation was used to avoid iteration and to improve the calculation efficiency.Circle and ellipse figure with various contact angle was simulated and calculated by the fitting algorithm based on circle and ellipse.The results indicate that if the contact angle is small,the circle fitting algorithm has high accuracy regardless the circle or ellipse figure,and the former is better.If the contact angle is large,the two algorithms have high accuracy for the circle figure,and the ellipse fitting algorithm has relative high accuracy for the ellipse figure.If droplet volume is small,the circle fitting algorithm should be used,otherwise the circle fitting algorithm should be used.The critical contact angle for algorithm selection is given in different ellipse eccentricity.Real globule figure of RTV （room temperature vulcanization） silicone rubber is calculated by the two algorithms,the results are closed to the simulated results,in the meantime,ellipse eccentricity and calculation result difference between the two algorithms will increase with the globule volume.

关 键 词：室温硫化 憎水性 接触角 拟合 圆 椭圆 体积 

分 类 号：TB303[一般工业技术—材料科学与工程]