Learning Forum

[emrehangursoy]

Dear Madam/Sir,

I want to investigate the heat transfer effect of ultrasonic vibration. For this purpose, I have formed a basic fluid domain like a smooth tube with L=500 mm (3D) as given in the attachment. I want to apply ultrasonic vibration on the middle section of this domain and I split the surface with the help of the face split tool. After that, I meshed the fluid domain, classically.

After that, I formed a UDF code (DEFINE_PROFILE) to solve the ultrasonic vibration in ANSYS Fluent. At this point, I have a question for you. How do I identify the UDF code as a boundary condition for the middle section wall of the fluid domain? Also, is it required to use the dynamic mesh although there is no solid?

Thank you for the information.

Best regards. 

 

[Atharva Nagarkar]

Hello,

Please check this link from the Ansys Customization Manual to understand how to hook the DEFINE_PROFILE UDF to the appropriate boundary.

6.2.25. Hooking DEFINE_PROFILE UDFs (ansys.com)

Alternatively, I would recommend you to consider using Expressions instead of using a UDF to provide the vibration. The Fluent Expression Language is an interpreted, declarative language based on Python, that enables you to specify complex boundary conditions and source terms with respect to time, iteration number, position, and solution variables. The interface is intuitive and it is easy to write the required Expressions. Please check the link from the Ansys User Guide below to understand how to write Expressions in Ansys Fluent as well as attach them as a boundary condition.

5.1. Introduction to Expressions (ansys.com)

If you are not able to access the link, please refer to this forum discussion: Using Help with links (ansys.com)

Thanks!