Difficult convergence due to NO-smooth transition

danle96 · November 11, 2016, 07:37

A part of my problem that I will talk later,
The main question is: How I in Star CCM+could control the transition between Prism Layers and the rest of the mesh

I'm using a 3D mesh polyhedral with the porpoise to mesh front and rear wing of a Formula Student car, for this reason I'm using a superficial treatment for each element searching a y+ results and also a volumetric control that works as a refinement, in my case 1200 iterations isn't enough to fix the TKE under decimal values and I suppose this could be solved by applying a smooth transition, and that's the main thing

me3840 · December 19, 2016, 01:37

I don't really understand what your question is. You want a better transition to the core mesh?

The prism layer mesher has several inputs. In general for external aero, it is preferable to choose the number of layers, total thickness, and first layer thickness. The last layer thickness is a result of those 3 choices. You must iterate through different settings to get you the last layer height you want.

November 11, 2016, 07:37	Difficult convergence due to NO-smooth transition	#1
danle96 New Member Barcelona Join Date: Nov 2016 Posts: 1 Rep Power: 0	A part of my problem that I will talk later, The main question is: How I in Star CCM+could control the transition between Prism Layers and the rest of the mesh I'm using a 3D mesh polyhedral with the porpoise to mesh front and rear wing of a Formula Student car, for this reason I'm using a superficial treatment for each element searching a y+ results and also a volumetric control that works as a refinement, in my case 1200 iterations isn't enough to fix the TKE under decimal values and I suppose this could be solved by applying a smooth transition, and that's the main thing

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December 19, 2016, 01:37		#2
me3840 Senior Member Join Date: Nov 2010 Location: USA Posts: 1,232 Rep Power: 25	I don't really understand what your question is. You want a better transition to the core mesh? The prism layer mesher has several inputs. In general for external aero, it is preferable to choose the number of layers, total thickness, and first layer thickness. The last layer thickness is a result of those 3 choices. You must iterate through different settings to get you the last layer height you want.