lmdad Uddin Chowdhury

 

PhD Scholar

Open-surface passive manipulation of interface on different surfaces using wettability patterning

I am working on droplet microfluidics with the primary objective of optimizing the Lab-on-a-chip system by introducing all functionalities on an open surface platform. This will help to avoid the fabrication of micro-channels, which is time-consuming, and at the same time, it is costly. Few Lab-on-a-chip functionalities in droplet microfluidics prospective include droplet sorting, splitting, metering, mixing, etc. which can be performed passively in open surfaces. Passive droplet transport on an open surface is accomplished by creating a wettability gradient. The droplet moves on such a surface due to the curvature difference between the front and back of the droplet. Three distinct regimes of droplet transport on surfaces with different wettability gradient and confinement are identified. Although the mixing of two droplets on an open surface can be done easily by using wettability patterning, however, it is quite challenging to split a droplet in the absence of external stimuli because of the interfacial energy of the droplet. A standalone power free technique for transport and splitting of a droplet on an open surface using continuous wettability-gradients is developed.

Bubble manipulation on shape gradient surface:

The generation of bubbles at the fluid is a common phenomenon. When a lighter liquid sits on the top of the dense fluid, the bubble generated at the heavier fluid sometimes may get stuck at the fluid-fluid interface. To get the bubble detached from the fluid-fluid interface, an aerophilic cone is placed vertically just above the fluid-fluid interface. Numerical modeling of such a three-phase situation is performed in COMSOL Multiphysics, while the experiment is underway. 

Research Experience:

6 months of research experience in Nanoengineered System Lab, Mechanical Engineering Department, University College London, UK.  I have explored different fabrication strategies for the development of Nano-engineered surfaces for energy and healthcare applications.

Journal Publications:  

  1. Imdad Uddin Chowdhury, Pallab Sinha Mahapatra, Ashis Kumar Sen, Self Driven Droplet Transport: Effect of Wettability Gradient and Confinement, Physics of Fluids, 31(4), 2019
  2. Imdad Uddin Chowdhury, Pallab Sinha Mahapatra, Ashis Kumar Sen, Shape evolution of drops on surfaces of different wettability gradients, Chemical Engineering Science, 2020 (under review)
  3. Imdad Uddin Chowdhury, Pallab Sinha Mahapatra, Ashis Kumar Sen, Arvind Pattamatta, Manish K Tiwari, Autonomous droplet transport and splitting on open surface, Langmuir, 2020 (under review)

 Conferences:

  1. Imdad Uddin Chowdhury, Pallab Sinha Mahapatra, Ashis Kumar Sen, Numerical Analysis of Droplet Transport on Different Wettability Gradient, FMFP-2018: 7st International Conference on Fluid Mechanics and Fluid Power, 10-12 December 2018, IIT Bombay, Mumbai, India
  2. Imdad Uddin Chowdhury, Pallab Sinha Mahapatra, Ashis Kumar Sen, Manish K. Tiwari, Shape locking phenomena during the droplet transport on different energy gradient surfaces, DROPLETS-2019, 16-18 September 2019, Durham University, Durham, UK
  3. Imdad Uddin Chowdhury, Pallab Sinha Mahapatra, Ashis Kumar Sen, Droplet transport on a Y shaped wettability gradient track, IHMTC-2019: 3rd International Conference on Heat and Mass Transfer, 28-31 December 2019, IIT Roorkee, Roorkee, India
  4. Manotosh Baidya, Imdad Uddin Chowdhury, Pallab Sinha Mahapatra, Ashis Kumar Sen, Numerical study of droplet impact on wettability patterned surface, IHMTC-2019: 3rd International Conference on  Heat and Mass Transfer, 28-31 December 2019, IIT Roorkee, Roorkee, India.