One-layer particle level set (OPLS) has been developed by using Lagrangian particles that are employed to correct both advection and re-initialization procedures of the level set function. In which, a level set function is utilized to smooth physical properties of the interface, while onelayer Lagrangian particles are used to track the interface directly. This method exhibits excellent mass conservation properties compared to the LS method. As a special aspect, the OPLS method enables management of merging and stretching of interface in an effective way. This capability is similar to the particle level set (PLS) method. However, the new approach of the OPLS method offers a more straightforward technique. This approach is validated with classical benchmark test cases, such as the long term advection of a circle, rotation of a slotted disk, single vertex in a box, merging and separating of circle. The results from the proposed method show good agreement with the numerical experiments published results and the OPLS method is verified to be highly reliable and accurate.

Purpose Moving interface problems exist commonly in nature and industry, and the main difficulty is to represent the interface. The purpose of this paper is to capture the accurate interface, a novel three-dimensional one-layer particle level set (OPLS) method is presented by introducing Lagrangian particles to reconstruct the seriously distorted level set function. Design/methodology/approach First, the interface is captured by the level set method. Then, the interface is corrected with only one-layer particles advected with the flow to ensure that the level set function value of the particle is equal to 0. When interfaces are merged, all particles in merged regions are deleted, while the added particles near the generated interface are used to determine the interface as the interface is separated. Findings The OPLS method is validated with well-known benchmark examples, such as the long-term advection of a sphere, the rotation of a three-dimensional slotted disk and sphere, single vortex in a box, sphere merging and separation, deformation of a sphere. The simulation results indicate that the proposed method is found to be highly reliable and accurate. Originality/value This method exhibits excellent conservation of the area bounded by the interface. The extraordinary performance is also shown in dealing with complex interface topological changes.