A particle manipulation method and its experimental study based on opposed jets.

A particle manipulation method was presented in this paper based on opposed jets. In such a method, particles were trapped near the stagnation point of the flow field and moved by controlling the position of the stagnation point. The hold direction of the flow to the particle was changed by changing the orientation of the opposed-jet flow field where a particle is trapped. Subsequently, the directional and quantitative movement of the particle in any direction was achieved. Taking micron particles as examples, we analyzed the control mechanism of particles based on opposed jets and evaluated the influence of jet velocity, inner diameter, distance of end face, radial error, and position of capillaries on the particle control performance by simulations. The feasibility of the proposed method was proved by a great number of experiments, and the results demonstrated that particles with the arbitrary size and shape can be trapped and moved directionally and quantitatively by constructing an opposed-jet flow field. The trapping and position control of particles can be manipulated without any contact with proper flow field parameters.