i want to simulate a upwrad flow of water in a circular pipe with gravity, the property of water is defined by UDF. when i set the property as constant it gets to convergence, but once i use my UDF, it divergenes. there is nothing wrong with my UDF! i try diffirent dicretion methods for pressure, eg. second order¡¢body force weighted and so on. Can anybody give me help!

use the pressure inlet and outlet B.C.

why u r using udf for your fluid prop.?