# CFX - fatal error

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 June 18, 2015, 07:55 CFX - fatal error #1 New Member   shashank Join Date: Jun 2015 Posts: 4 Rep Power: 8 I am modelling an ejector. It has a nozzle inlet for water and another inlet for air perpendicular to water inlet and above the nozzle outlet. I am using CFX multiphase option. For inlet velocities of water 2ms-1, 4 ms-1, 6ms-1, the solution worked fine. It did not converge but it did give a stable solution after 7000 iterations. Now for inlet velocity 21ms-1 , i am getting the error - Fatal error in linear solver. Boundary conditions were , inlet-water : inlet inlet-air : opening outlet : outlet ( the solver suggests to put it as opening but for opening condition it asks for volume fraction for phases which we do not know) the solution gives error after some 500 iterations. Any idea how i can rectify this error ?

 June 18, 2015, 07:56 #2 New Member   shashank Join Date: Jun 2015 Posts: 4 Rep Power: 8 A wall has been placed at portion(s) of an INLET | | boundary condition (at 100.0% of the faces, 100.0% of the area) | | to prevent fluid from flowing out of the domain. | | The boundary condition name is: inletair. | | The fluid name is: water. | | If this situation persists, consider switching | | to an Opening type boundary condition instead. | +--------------------------------------------------------------------+ +--------------------------------------------------------------------+ | ****** Notice ****** | | A wall has been placed at portion(s) of an INLET | | boundary condition (at 100.0% of the faces, 100.0% of the area) | | to prevent fluid from flowing out of the domain. | | The boundary condition name is: inletair. | | The fluid name is: air. | | If this situation persists, consider switching | | to an Opening type boundary condition instead.

 June 18, 2015, 18:46 #3 Super Moderator   Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 16,759 Rep Power: 131 These FAQs are relevant: http://www.cfd-online.com/Wiki/Ansys...do_about_it.3F http://www.cfd-online.com/Wiki/Ansys...f_an_OUTLET.22 The backflow at the inlet may well be caused by the convergence problem. Check the result in CFD-Post to see whether it is likely to be real or not. If it is real then you will need to adjust your simulation to handle it.

 June 19, 2015, 02:55 #4 New Member   shashank Join Date: Jun 2015 Posts: 4 Rep Power: 8 oh.. okay. Thank you.