Hi rudolf , Could you please be specifically what information you are looking as it over fluent . As if you want to model it and analysis then its an easy task in fluent package I will help you over there but please provide some details regarding what information you are looking for and what analysis you are gonna do it over fluent.

@Shrish thank you for your quick reply.

Yes i want to model it and analysis on fluent as defining the appropriate properties and schemes... You will find below an attached pic of the model i want to study.

My study is about the heat transfer performance and limits of a vertical, two-phase, closed thermosyphon , most of it includes its boundary layer, flooding onset , Heat Transfer Rate vs Working Fluid Inventory, Heat Transfer Rate vs Condenser Cooling Water Flow Rate , Maximum Heat Transfer Rate vs Aspect Ratio , Flooding Limited Liquid Film Reynolds Number vs Size Factor , investigating the effects of working fluid inventory, evaporator wall temperature and condenser cooling capacity ......

Thank you so much in advance.

Dear Rudolf, as far as heat transfer is concerned I recommend you to use ICEMCGF of Ansys 13.0 or higher . ICEMCFD is much simpler and extremely user friendly meshing software. Please be very cleat from the onset of this project that ICEM is designed to carry out just meshing. Other CAD software are available for modeling purposes like CATIA, ProEngg, SolideEdge, SolidWorks, Gambit, many many more in open source software. Now what ICEM will help you is to correctly model BL inside your geometry . What's going on inside BL is main thrust of your research as far as I got it . Pl correct me if I am wrong. All viscous effects from which heat transfer occur starts from BL so you really need to look into the exact viscous and thermal BLs. John D Anderson Jr. Book on Aerodynamics and Scheligton book on BL will surely help you out for BL Analytical Solution. Computational results are Garbage IN Garbage OUT if not validated from either analytical OR Computational Efforts. Thus doing CFD with solid understanding of Academic literature review is a MUST. I recommend to go for LES or at least SST K-w turbulence model with Y+ of close to 1. This way you with surely capture BL Separation and can model Heat Transfer to its reality . Hopes I have answered your query. Take Care and Merci..

Dear Rudolf I forgot to mention one of the chapters in Fluent Manuals regarding Multi Phase Flow. Please have a look of it too before you proceed further . Regards .

Dear Taimur thank you so much for your reply. Regarding ICEMCFD i will definitely have a look at it and try to use it, but as far as my project requires me to use gambit for meshing and export it to fluent. Your information really helped me going further with my studies.

My concern is the trial and error of the drawn meshes that i have to do as also as trying different properties and schemes selections in fluent and compute them before i get some logic results. Analytical results are currently being studied as well.

Again thank you so much.

Dear Rudolf

I have all literature review regarding ICEM CFD which very easy to learn. Trust me it is very difficult to model exact BL in Gambit where as "Prism elements" are peanuts in ICEM CFD ; which are used to model BL. It is a form of tetrahedral elements which has a base of box. Hopes you get it. Thus forBL prisms are best. So if you are comfortable with Gambit , go for it regarding unstructured mesh. I recommend to export *.mesh file from Gambit and import it in ICEM. Now edit it for Prism elements and then again export it to *.mesh. Now import it again in Gambit. Finalize optimized mesh using any one core property of your research.In fluent sstkw is best to capture vortices and heat transfer rates. Go for mesh independence and then turbulence model independence both . If your research is unsteady please keep it in mind that time step independence "Delta T" needs to looked into . Merci.