{"id":408830,"date":"2025-02-07T13:41:32","date_gmt":"2025-02-07T13:41:32","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fluent-species-transport-amp-multiphase-chemical-flow-simulation\/"},"modified":"2025-02-07T13:41:32","modified_gmt":"2025-02-07T13:41:32","slug":"fluent-species-transport-amp-multiphase-chemical-flow-simulation","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fluent-species-transport-amp-multiphase-chemical-flow-simulation\/","title":{"rendered":"Fluent Species Transport & Multiphase Chemical Flow Simulation"},"content":{"rendered":"

<p>Hello,<\/p><p>I’m new to chemical flow simulations and currently using ANSYS Fluent 2024 R2 (Student Version) to model CO\u2082 injection onto a stationary Ca(OH)\u2082 slurry. The goal is to simulate CO\u2082 diffusion, dissolution, and reaction leading to CaCO\u2083 precipitation. Due to hardware limits (4 cores, mesh restrictions), I’m working in 2D.<\/p><h3>Key Questions:<\/strong><\/h3><\/p>\n

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  1. How to define CO\u2082 diffusion into slurry correctly?<\/strong> Should the slurry initially be modeled as just Ca(OH)\u2082 + water<\/strong>, with CO\u2082 diffusing into it over time, or should CO\u2082 be included in the slurry phase from the start?<\/li>\n
  2. How to define reaction and mass transfer?<\/strong> How should I correctly set up the dissolution of CO\u2082<\/strong> into the slurry and its reaction with Ca(OH)\u2082<\/strong>? Should mass transfer between phases be explicitly defined?<\/li>\n<\/ol>\n

    <h3>Current Setup:<\/strong><\/h3><\/p>\n

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    • Multiphase Model:<\/strong> Eulerian with three phases:\n
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      • Gas phase<\/strong>: Initially <\/strong>stationary air; CO\u2082 injected at 6 mL\/s (approx. 45 m\/s) from a 0.41 mm nozzle. (Defined as an air-CO\u2082 mixture since Fluent requires multiple species per phase.)<\/li>\n
      • Slurry phase<\/strong>: Ca(OH)\u2082 + water, defined as a fluid with solid properties.<\/li>\n
      • CaCO\u2083 solid phase<\/strong>: Defined as <\/strong>granular fluid <\/strong>due to Fluent’s multiphase restrictions.<\/li>\n<\/ul>\n<\/li>\n
      • Turbulence Model:<\/strong> Realizable k-ε with scalable wall functions.<\/li>\n
      • Initial Condition:<\/strong> Domain starts filled with stationary air.<\/li>\n<\/ul>\n

        <h3>Issues & Questions:<\/strong><\/h3><\/p>\n

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        1. Divergence Problems:<\/strong> The simulation immediately diverges (most probably because of boundary conditions). Any suggestions on stabilizing it?<\/li>\n
        2. Material Definition:<\/strong> Is defining <\/strong>CaCO\u2083 as a granular fluid the right approach?<\/li>\n
        3. Boundary Condition for Slurry:<\/strong> Should it be stationary (wall or pressure outlet?) or have a small velocity (currently 1e-6 m\/s inlet)?<\/li>\n
        4. Chemkin Availability:<\/strong> Chemkin doesn’t appear as an option in Species Transport. Is it available in the Student Version? If not, what alternatives can I use?<\/li>\n
        5. Tracking pH Variations:<\/strong> What’s the best way to compute and visualize pH in Fluent?<\/li>\n
        6. Measuring CO\u2082 Diffusion Depth:<\/strong> How can I track how deep CO\u2082 penetrates into the slurry before reacting?<\/li>\n<\/ol>\n

          <p>Since I’m still learning how to correctly model multiphase chemical flows, any guidance would be really helpful!<\/p><p>Thanks in advance.<\/p><\/p>\n","protected":false},"template":"","class_list":["post-408830","topic","type-topic","status-publish","hentry","topic-tag-fluent-cfd-ansys-1","topic-tag-multiphaseudfevaporationdpmspeciestransportdefinesourcesourcetermeulerianlagrangian-1","topic-tag-chemical-kinetics","topic-tag-chemical-reaction","topic-tag-eulerian-multiphase-model-1","topic-tag-Interphasemasstransfer-1","topic-tag-mixture-of-material"],"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