Design of a ferrofluid micropump using a topology optimization method

This paper illustrates, through a practical example, the interest and the potential of topology optimization methods when they are integrated in the design process of electromagnetic devices. The topology optimization tool used in this paper combines a genetic algorithm optimization, the NSGA-II, a material distribution formalism based on Voronoï cells and a commercial finite-element evaluation tool, COMSOL Multiphysics. The practical example considered is a volumetric micropump using a ferrofluid bubble actuated by a fixed electromagnetic structure, as a piston in a pipe. The topology optimization tool is applied to an earlier stage of the design in order to find the best way to confine the bubble in the pipe. The result is then used to produce a structure similar to a stepper motor, able to move the ferrofluid bubble, and thus to generate the desired pumping effect.