Heat exchanger velocity field with laminar inlet condition

Numerical simulation and LDV measurements are performed for laminar inlet f low condition in a vortex exchange chamber with isothermal conditions. Newt onian and non-Newtonian fluids were used. Experimental measurements are com pared to results of numerical computations with good agreement. Both show t he existence of a secondary flow generated by hydrodynamical instabilities due to streamline curvature. The main vortex flow appears then to be restri cted by this secondary flow. (C) 2001 Academie des sciences/Editions scient ifiques et medicales Elsevier SAS.