{"id":40496,"date":"2020-01-29T17:47:06","date_gmt":"2020-01-29T17:47:06","guid":{"rendered":"\/forum\/forums\/topic\/uds-equation-is-not-reflected\/"},"modified":"2020-01-29T17:47:06","modified_gmt":"2020-01-29T17:47:06","slug":"uds-equation-is-not-reflected","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/uds-equation-is-not-reflected\/","title":{"rendered":"UDS equation is not reflected"},"content":{"rendered":"

I have just started using ANSYS FLUENT. If you have any knowledge, I hope you can help.<\/p>\n

<\/p>\n

There are several tubes in a square space, and water vapor and hydrogen exist uniformly at an arbitrary volume fraction. A pressure boundary is set between the upper surface of the square space and inside the tubes. The thick part of the tubes is set as a porous zone, and only one substance (water-vapor or hydrogen) flows into the tube due to the viscous resistance of the porous. Multiphase flow model is used to set the porous viscous resistance for each substance. At present, material diffusion is not incorporated, so the UDS equation was set. However, the values of uds0 and uds1 are all 0 on the console screen of Fluent. Please tell me about this cause. Is nothing entered in Φk of the UDS equation with the current settings?<\/p>\n

<\/p>\n

Here are the current settings.<\/p>\n

<\/p>\n

<Models><\/p>\n

<\/p>\n

Multiphase – Eulerian (Phase1 water-vapor, Phase2 hydrogen)<\/p>\n

<\/p>\n

Energy – On<\/p>\n

<\/p>\n

Viscous – Standard k-e<\/p>\n

<\/p>\n

Radiation\/Heat Exchanger\/Species\/Discrete phase\/Acoustics\/Eulerian Wall Film – Off<\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

<UDS><\/p>\n

<\/p>\n

?uds-0    Inlet Diffusion – On<\/p>\n

<\/p>\n

Phase – water-vapor (Phase1)<\/p>\n

<\/p>\n

Solution Zones – all fluid zones, Flux Function – mass flow rate, Unsteady Function – default<\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

?uds-1    Inlet Diffusion – On<\/p>\n

<\/p>\n

Phase – hydrogen (Phase2)<\/p>\n

<\/p>\n

Solution Zones – all fluid zones, Flux Function – mass flow rate, Unsteady Function – default<\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

?Source Terms – Off (all cell zone)<\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

?UDS Diffusion Coefficients<\/p>\n

<\/p>\n

water-vapor – constant (e.g. 1.0e-5), hydrogen – constant (e.g. 1.0e-5)<\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

?UDS Boundary Condition<\/p>\n

<\/p>\n

Specific Flux – 0 (all boundary including inlet and outlet)←default settings<\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

<Initialization (Initial Values)><\/p>\n

<\/p>\n

User Scalar 0 :0, User Scalar 1 :0<\/p>\n

<\/p>\n

\"\"<\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

 <\/p>\n

<\/p>\n

Thank you for reading to the end.\"\"<\/p>\n","protected":false},"template":"","class_list":["post-40496","topic","type-topic","status-closed","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\n\t\t\n\t\t\n\t\t