{"id":462582,"date":"2026-08-13T07:54:38","date_gmt":"2026-08-13T07:54:38","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/mass-transfer-models-for-solidliquid-phase-change-in-cfx-2019-r2\/"},"modified":"2026-08-13T07:54:38","modified_gmt":"2026-08-13T07:54:38","slug":"mass-transfer-models-for-solidliquid-phase-change-in-cfx-2019-r2","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/mass-transfer-models-for-solidliquid-phase-change-in-cfx-2019-r2\/","title":{"rendered":"Mass Transfer Models for Solid\u2013Liquid Phase Change in CFX 2019 R2"},"content":{"rendered":"

Question About Mass Transfer Models for Solid–Liquid Phase Change in CFX 2019 R2<\/strong><\/p>\n

Dear everyone,<\/p>\n

I am currently using ANSYS CFX 2019 R2<\/strong> to simulate a solid–liquid phase change process, in which Solid A (treated as Liquid A)<\/strong> melts into Liquid B<\/strong>.<\/p>\n

Since CFX does not have a built-in solid–liquid phase change model, we are considering treating Solid A as a fluid (Liquid A). The viscosity of Liquid A is defined as very high at low temperatures and decreases significantly as the temperature increases, so that its behavior approximates that of a solid at low temperatures and a liquid at high temperatures.<\/p>\n

At the initial time, the computational domain contains both Solid A (treated as Liquid A)<\/strong> and Liquid B<\/strong>. We place both phases in the same fluid domain<\/strong>, as shown in Figure 1.<\/p>\n

The initial volume fractions are defined according to the spatial distribution shown in Figure 2.<\/p>\n

Our main question is about the mass transfer model<\/strong> between the two phases. As shown in Figure 3, CFX provides options such as Phase Change<\/strong> and Specified Mass Transfer<\/strong>.<\/p>\n

For this type of solid–liquid phase change, where Solid A (treated as Liquid A) gradually melts into Liquid B as the temperature increases:<\/p>\n

    \n
  1. \n

    Which mass transfer model should we use: Phase Change<\/strong> or Specified Mass Transfer<\/strong>?<\/p>\n<\/li>\n

  2. \n

    Which model is more appropriate for representing the melting process?<\/p>\n<\/li>\n

  3. \n

    If Specified Mass Transfer<\/strong> is recommended, how should the mass transfer rate be defined as a function of temperature or liquid fraction?<\/p>\n<\/li>\n

  4. \n

    Are there any other settings or considerations that should be taken into account when implementing this phase change model in CFX 2019 R2?<\/p>\n<\/li>\n<\/ol>\n

    Any advice or suggestions would be greatly appreciated.<\/p>\n

    Thank you very much for your help!<\/p>\n

     <\/p>\n

     <\/p>\n","protected":false},"template":"","class_list":["post-462582","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t