{"id":17619,"date":"2018-11-24T17:08:15","date_gmt":"2018-11-24T17:08:15","guid":{"rendered":"https:\/\/www.simscale.com\/?page_id=17619"},"modified":"2025-07-17T16:28:30","modified_gmt":"2025-07-17T16:28:30","slug":"multiphase-fluid-flow-analysis","status":"publish","type":"page","link":"https:\/\/www.simscale.com\/docs\/analysis-types\/multiphase-fluid-flow-analysis\/","title":{"rendered":"Multiphase Fluid Flow Analysis"},"content":{"rendered":"\n\n\n\n\n

The multiphase<\/strong> fluid flow analysis is used to simulate the time-dependent behavior of two incompressible, isothermal, immiscible fluid mixtures using the VOF (Volume of Fluid) method. Please be aware that currently, the multiphase analysis is limited to flow speeds up to 15 \\( \\frac{m}{s}\\).<\/p>\n\n\n\n

\"waterfall<\/a>
Figure 1: Multiphase flow simulation of a waterfall<\/figcaption><\/figure>\n\n\n\n

Creating a Multiphase Analysis<\/h2>\n\n\n\n

To create a multiphase analysis, the first step is to select the desired geometry and then click on ‘Create Simulation<\/strong>‘:<\/p>\n\n\n

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\"creating<\/a>
Figure 2: Creating a new multiphase analysis<\/figcaption><\/figure>\n<\/div>\n\n\n

Afterward, a window with available analysis types appears as follows: <\/p>\n\n\n

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\"multiphase<\/a>
Figure 3: Steps to create a multiphase analysis in SimScale<\/figcaption><\/figure>\n<\/div>\n\n\n
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<\/i>Specialized Analysis Type<\/p>\n <\/div>\n

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Multiphase<\/em> is a specialized analysis type restricted to users with a paid plan. For more details please visit our product & pricing page<\/a> or contact sales.
<\/p>\n <\/div>\n<\/div>\n\n\n\n

Choose the ‘Multiphase<\/strong>‘ analysis type from the list and confirm your choice by clicking the ‘Create Simulation<\/strong>‘ button. The following simulation tree with the corresponding settings should appear:<\/p>\n\n\n

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\"simulation<\/a>
Figure 4: Simulation tree showing entries for a multiphase analysis type.<\/figcaption><\/figure>\n<\/div>\n\n\n
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<\/i>Multiphase using Multi-purpose analysis type<\/p>\n <\/div>\n

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Users can now perform multiphase simulations within the Multi-purpose analysis type<\/a> as well for transient simulations.\r\nThe Multiphase<\/em> toggle appears under the global settings.
Some advantages over the traditional multiphase solver are:

  • Quick and stable convergence with automatic CFL adjustment
  • Robust binary tree based mesher
  • Parameterization and CAD associativity<\/li> \n <\/div>\n<\/div>\n\n\n\n
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    Multi-purpose Multiphase<\/a><\/blockquote>