Hi guys i’m facing the problem of the evaluation of the drag coefficient for a poiseuille flow past a cylinder confined in a rectangular channel.
i’m using zou he boundaries at inlet (imposed parabolic profile) and outlet ( fixed density) while using half way bounce back on the channel walls.
i’m not doing any corner special treatment.
on the cylinder i’m using the Bouce back On Links as proposed by Ladd in the paper:
Numerical Simulations of Particulate Suspensions via a Discretized Boltzmann Equation Part I. Theoretical Foundation
the interior of the cylinder is fluid and is moved and bounced back as a normal fluid.
I use the Moment Exchange method to evaluate the Force on the cylinder.
I’m comparing the Drag coefficient Cd resulting with finite element simulations carried on with COMSOL. and with results from this paper:
LATTICE BOLTZMANN SIMULATION OF FLOW OVER A CIRCULAR CYLINDER AT MODERATE REYNOLDS NUMBERS
Dharmaraj ARUMUGA PERUMAL a*, Gundavarapu V.S. KUMAR band ANOOP K. DASS b
i’m getting for almost every Reynolds number investigated Drag coefficients which are way bigger than the values obtained with COMSOL or found in that paper.
the odd thing is that comparing the flow field around the cylinder obstacle with finite element results they are similar.