Commun. Comput. Phys., 12 (2012), pp. 577-594. A Constrained Level Set Method for Simulating the Formation of Liquid Bridges Dongdong He 1, Huaxiong Huang 1*1 Department of Mathematics and Statistics, York University, Toronto, Ontario, Canada M3J 1P3. Received 18 November 2010; Accepted (in revised version) 9 August 2011 Available online 20 February 2012 doi:10.4208/cicp.181110.090811s Abstract In this paper, we investigate the dynamic process of liquid bridge formation between two parallel hydrophobic plates with hydrophilic patches, previously studied in [1]. We propose a dynamic Hele-Shaw model to take advantage of the small aspect ratio between the gap width and the plate size. A constrained level set method is applied to solve the model equations numerically, where a global constraint is imposed in the evolution [2] stage together with local constraints in the reinitialization [3] stage of level set function in order to limit numerical mass loss. In contrast to the finite element method used in [2], we use a finite difference method with a 5th order HJWENO scheme for spatial discretization. To illustrate the effectiveness of the constrained method, we have compared the results obtained by the standard level set method with those from the constrained version. Our results show that the constrained level set method produces physically reasonable results while that of the standard method is less reliable. Our numerical results also show that the dynamic nature of the flow plays an important role in the process of liquid bridge formation and criteria based on static energy minimization approach has limited applicability. AMS subject classifications: 76T99, 65M06 Notice: Undefined variable: pac in /var/www/html/issue/abstract/readabs.php on line 164 Key words: Constrained level set method, Hele-Shaw, liquid bridges, mass conservation, moving interface. *Corresponding author. Email: ddonghe@yorku.ca (D. He), hhuang@yorku.ca (H. Huang)