Mechanical Engineering
Graduate Seminar
NOTICE OF SEMINAR PRESENTATION
CANDIDATE: Avishek Deb
DEGREE SOUGHT: MASc
DATE: 7/3/2026
TIME: 11:30am
PLACE: Room 1101 CEI
TITLE: Modelling and Validation of a Rapidly Manufacturable Double Emulsion Microfluidic Droplet Generator with Integrated Sensing
Abstract
Double emulsion (water-in-oil-in-water) droplets are central to drug delivery, single-cell analysis, and high-throughput diagnostics, yet most existing generators rely on cleanroom-based photolithography or soft lithography that are slow, costly, and difficult to integrate with on-chip sensing. Prior studies have also tended to be either purely numerical or purely experimental, leaving a gap in combined, validated, manufacturable designs. This work presents a cross-junction double emulsion droplet generator that is rapidly fabricated by 3D printing in PLA and sealed with a transparent substrate, eliminating the need for cleanroom processing. A dual level-set multiphase model is developed in COMSOL to track the three immiscible phases and capture the sequential core–shell breakup, with droplet size governed by the capillary and Weber numbers across a range of inner, shell, and continuous-phase flow rates. The model is validated against experiments performed on the fabricated device using syringe-pump-driven flow and digital microscopy, with simulated and measured droplet diameters showing close agreement (within roughly 9%) over part of the operating range and larger deviations at higher flow-rate ratios. Building on the validated platform, an integrated capacitive sensing scheme using embedded copper electrodes is introduced to distinguish inner droplets, outer droplets, and complete double emulsion structures from their dielectric response, enabling real-time, label-free droplet characterization. Together, the combined numerical, experimental, and sensing approach offers a low-cost, rapidly manufacturable route to controllable double emulsion generation with on-chip readout.