Numerical investigation of secondary flow effect in cone–plate viscometer

• The flow in cone–plate is multi-directional and significant secondary flows are present for Re > 4.
• Accurate wall shear stress distribution is obtained.
• Modified and improved experimental results are obtained.

A secondary flow in cone-and-plate viscometers is numerically studied by solving the equations of motion for steady incompressible flow of Newtonian fluids. The assumption of the unidirectional flow is not valid in general, and the actual cone and plate apparatus has a limited finite domain. Geometric and flow parameters are numerically studied to determine their influence on the secondary flow. Numerical investigations show that the flow in these devices is multi-directional and significant secondary flows are present for Reynolds numbers greater than 4. Moreover, it is found that the edge has a significant effect on the fluid flow behavior. The numerically predicted wall shear stress distribution differs significantly from the primary flow solution. Modified and improved experimental results obtained by the cone and plate method are presented. A torque correction formula is derived as a function of Reynolds number to account for the secondary flow effect.