Fluid-structure interaction in periodic structure

Fluid-Structure Interaction (FSI) is defined as a combination of law and fluid dynamics and the relevant structural mechanics and the term FSI has given the best description of itself which is the interactions between fluid and structures. Periodic structures such as the Deterministic Lateral Displacement (DLL) array which is a microfluidics technology, first introduced by Huang et al, and the array enables micro-scaled particles to be sorted passively. The DLD array is fabricated in a microfluidics device through a series of microfabrication procedures. Here, we examine the interactions of fluorescent dyed particles in micro-size along with the fluid flow against the DLD array, and we also examine the influence of the fluid flow behaviours on the particle movements in the arrays through fluorescence microscopy. Micro particle tracking velocimetry (μPTV)is a measurement technique for particle velocity in micro-size. It is usually used to quantify particle to particle differences through a set of algorithms such as particle image tracking particle image analysis. Hence Matlab codes, based on the concept of μPTVtechnique, are provided to run a number of videos which have recorded micro-sized particle movement to generate the velocity vector field in the DLD array. The results of the vector fields processed by Matlab codes are generally idea, but the vectors in some areas of the image are not detected or quantified. Somehow, we haven't achieved the object of this project, which is tracking a moving particle, but we are getting there. Therefore, the properties of microscopy and the algorithms in Matlab code need to be optimised for future work.