Functionalized alginate microparticles for fluid flow visualization

Several methods are available for measuring the fluid movement in experimental setups. One of the most used technique is the particle image velocimetry (PIV). This is an optical technique that indirectly measures the fluid velocity by measuring the displacement of some small particles that seeds the fluid. To obtain the velocity field, the zone of interest of the experimental setup is illuminated twice with a laser beam. Two consecutive images are obtained and the displacement of the particles can be calculated. Knowing the time difference between both images allow to compute the velocity. Appropriate flow seeding is particularly critical in PIV. Particles that follow the flow accordingly and scatter enough light must be used in order to obtain accurate velocity field of the flow. Therefore, particles should be as small as possible in order to ensure good tracking of the fluid motion and they should not be too small, since they will not scatter enough light. Please click Additional Files below to see the full abstract