Hi Han,
Please refer to CFX user guide as an initial resource. Here is the link to Multiphase modeling guidelines from CFX user guide https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v231/en/cfx_mod/i1384390.html?q=multiphase
We cannot access links and cas files through the forum as Ansys employees.
Best regards