M6 Validation
1 Attachment(s)
Thanks for all the advice so far on this problem. I am still having the same problem with the M6 wing validation. The simulations work fine for any subsonic flow, however once the flow goes supersonic over the upper surface, the resulting pressure distribution is incorrect. A plot of the Mach number over the upper surface is attached and it shows 2 distinct regions of high speed flow. I have also done this simulation if fluent and it gives accurate results. in CFX, the region of high speed flow at the leading edge is smaller than fluent giving a smaller region of low pressure at the leading edge than is required. The aft region does not exist in fluent and in CFX it therefore gives a region of low pressure over the aft section where it should not be. I have a Y+ value of 1 or less on the wing.
Attachment 4849 Any ideas on where to proceed. Steve 
Do you know what is causing the 2 regions? A shock? Separation? Something else? That would give you a clue as to where to start looking.

M6 Validation
Thanks Glenn
I am not sure what is causing this problem. I have tried diffrent meshes, even without inflation layers, diffrent turbulence models, diffrent turb models. I have left turbulent wall functions on automatic, is it worth trying these. 
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I can't make heads or tails of your image, by the way. 
2 Attachment(s)
This is the basic setup I have been using.
General Options: Fluids List; Air Ideal Gas Reference Pressure; 1 atm Buoyancy Option; Non Buoyant Domain Motion; Stationary Fluid Models: Heat Transfer Option; Total Energy Inc Viscous Work Term Select Turbulence Model; SST Transitional Turbulence Select Turbulent Wall Functions; Automatic Far Field ( Inlet ) Flow Regime Option Subsonic Mass and Momentum Cart. Vel. & Pressure U = 270.715 V = 27.74 W = 0 Turbulence Option; Low Intensity 1% Heat Transfer, Static Temperature = 263 Downstream ( Outlet ) Flow Regime Option; Subsonic Mass and Momentum Option; Average Static Pressure, Relative Pressure; 0 Pa Pressure Averaging; Average Over Whole Outlet Inboard ( Symmetry ) Symmetry Wing ( Wall ) Wall Influence on flow  Wall, noslip / NoSlip Heat Transfer  Adiabatic Global Initial Conditions Velocity Type; Cartesian Cartesian Velocity Components; Automatic With Value, U = 270.715 m/s V = 28.74 m/s Static Pressure Option; Automatic Turbulence Kinetic Energy Option; Automatic Turbulence Eddy Dissipation (Select) Option; Automatic Solver Control Criteria Basic Settings: Advection Scheme Option; High Resolution Convergence Control; Automatic Timescale Max. Iterations; 1000 Length Scale Option Aggressive Convergence Criteria; Residual Type, Max Residual Target; 1e6 The domain is a parabolic one with a symmetry plane. the wing is level and the domain is inclined for the angle of attack. The pressure plot on the surface is fine for subsonic and low angle of attack. At the M0.84 and 5 degrees, the plot on the upper surface disagrees with the wind tunnel data. Attachment 4882 The mach number distribution in this region shows two areas of high speed flow. There should be only one region of high speed flow. Attachment 4883 
Your mach number plot gives the game away  if your contour lines are jagged like that then your mesh is too coarse. You need a finer grid. Your results on this coarse grid are rubbish.

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Thanks for the help.
I currently have 280 points on the upper surface, expanding away at a rate of 1.2. There is a boundary layer with ten layers giving a Y+ of 1. Is it the number of points or the expansion rate that I should be concentrating on. Steve 
Do a sensitivity study on all of them.

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