Projects

Current:

Development of parallel immersed boundary method code to study platelet transport and adhesion

This is the project I am working on at Penn. It is based on the code developed during my dissertation work. It used immersed boundary method to simulate deforming cells in blood. The fluid solver is based on the Lattice Boltzmann method due to its efficiency in parallel computing. The solid cell model is based on coarse grained molecular dynamics. The parallel feature is implemented with MPI.

2009-2015:

Influence of Red blood cells (RBCs) on Nanoparticle (NP) delivery in Microcirculation

Basically we study the interaction of RBCs and NPs and RBCs effect on NP transport, dispersion and binding. The motion and deformation of RBCs is captured through the Immersed Finite Element Method, while the motion and adhesion of individual NPs are tracked through Brownian adhesion dynamics using Monte Carlo method. With RBCs, a non-uniform NP distribution profile with higher particle concentration near the vessel wall is observed. Such distribution leads to over 50% higher particle binding rate compared to the case without RBCs. The tumbling motion of RBCs in the core region of the capillary is found to enhance NP dispersion, with dispersion rate increases as shear rate increases.

Characterization of NP distribution in microcirculation through a microfluidic device

This is experimental part of the above project. Microfluidic chip with same dimensions used in the simulation is fabricated in the clean room. Both with RBCs and without RBCs cases have been performed. With confocal microscope, we captured the fluorescent images of NPs in the channel. With RBCs, a higher concentration of NPs is observed in the near wall region; without RBCs, NP distribution is more uniform across the channel. The experimental test is consistent to the prediction of numerical model.

Microbubble generation and its interaction with particles under excitation of Ultrasound

Microvortex is generated around microbubbles under excitation of ultrasound. The microvortex can actively trap particles based on their size and excitation frequency. We have demonstrated the size selectivity of microbubbles. Right now we try to apply this technique to capture circulating tumor cells, enhance local concentration of molecules, etc.

2007-2009:

Maglev Line Track Irregularity effect on Riding Comfort and Safety

Track Irregularity influences transport safety, passenger travel comfort and railway maintenance cost. Train acceleration raw data has been integrated to obtain the deflection of the substructure. Digital signal filter was designed to filter the noise of the signal.