Modeling and Prediction of the Flow, Pressure and Holding Force Generated by a Bernoulli Handling Device

This paper presents the modeling and prediction of the air flow, pressure and holding force produced by a non-contact Bernoulli gripper, which is essentially a radial air flow nozzle, used to handle small and large, rigid and non-rigid materials. Previous studies have demonstrated the turbulent behavior of the flow and the presence of a flow separation region at the nozzle of the gripper. Here, a Reynolds stress model has been implemented in a finite volume based segregated Reynolds-Averaged Navier-Stokes solver. Compressible air is modeled to capture the effect of the high flow velocities generated by the nozzle. In addition an experimental set up is designed to validate the model. Experimental results of air pressure and force agree favorably with those predicted by the model. This model could be used to understand the influence of handling variables such as the stand-off distance and air flow rate on the suction pressure distribution and lifting force acting on the handled object.