Computational analysis of particle trajectories for enhanced separation efficiency in deterministic lateral displacement arrays

Deterministic lateral displacement (DLD), a passive microfluidic particle separation technique based on size-dependent behavior, has been widely used in biomedical and analytical applications. When modifying post geometries can influence particle separation performance, such approaches often face challenges due to unpredictable particle dynamics and fabrication constraints. In this study, we explore additional parameters such as inlet configurations and flow-rate ratios to enhance particle sorting efficiency in DLD arrays without complex structural modifications. Through numerical flow simulations across varying Reynolds numbers (Re), we identify stable flow regimes and demonstrate that a Re of 23.28 achieves particle separation. Particle trajectory was systematically analyzed depending on the inlet spacing and flow-rate ratios to optimize sorting performance. The results show peak separation efficiency at a flow-rate ratio of 1:4 with a 150 μm inlet distance under moderate-to-high Re condition of 23.28. This approach provides a practical and scalable alternative to complex structural modifications, enabling the development of high-throughput DLD arrays for advanced diagnostic and biosensing applications.