Influence of Contact Angle and Drop Volume on O'Brien's Model Based Static Contact Angle Algorithm

To improve the accuracy of the evaluated static contact angle and its measuring uncertainty for superhydrophobic surfaces, on the basis of the Laplace equation and the O'Brien's approximate model based height-width algorithm, the influence of the contact angle and the water drop volume on the errors of the contact angle and partial derivative theta/partial derivative H (the variation in the estimated contact angle with changes in the measured drop height) evaluated by the height-width algorithm is investigated. The results reveal that the errors of the evaluated contact angle and partial derivative theta/partial derivative H increase with increasing in contact angle or water drop volume.