识别传质主界面单元的算法：用于UDF编程的界面变形避免

This algorithm is proposed to identify the main interface cells for mass transfer calculation by alternately computing the face of each cell in the domain. It uses a connectivity macro to retrieve the liquid volume fractions of two adjacent cells C0 and C1 for each cell face. If the liquid volume fraction in a cell is greater than zero and is located next to a cell filled with vapor, the algorithm declares the cell as a main interface cell. Similarly, if a cell has a liquid volume fraction greater than zero and is located next to a main interface cell, it is identified as a minor interface cell. After identification, the interface area of the minor interface cells is added to the main interface cell, and the mass related to phase change is calculated on the main interface cell. Through a similar program, the calculated mass is moved from the main interface cell to the adjacent cell filled with vapor to avoid interface deformation in the udf programming.