Published in arXiv, 2025
In this paper, we analyze the contact network of highly bidisperse (4:1 size ratio) dense suspensions. We observe a remarkable difference in the nature of pair-wise interactions between particles compared to the lower bidisperse case. We also investigate the jamming tendencies and how the system approaches jamming.
Published:
We study arches that form during clogging in a 3D system of soft hydrogel particles (bulk modulus 10-30 kPa) in water flowing through a square cross-section tube with a circular outlet. The particles are dyed with a fluorescent dye and a laser sheet is used to locate the particles in 3D when the system clogs. The tube’s dimensions are 7.62 cm x 7.62 cm x 25.4 cm. The mean particle diameter is 1.46 cm. We vary the total number of particles from 80-125 and the diameter of the outlet from 2-3.5 cm. We measure the clogging probability, and the 3D particle positions in the clog to identify 3D arches. We find that the number of particles in the clogged arch depends on the width of the orifice and the number of particles.
Published:
Dense non-Brownian suspensions, found in industries like cement and chocolate, exhibit complex flow behavior influenced by shear and particle interactions. Using LF-DEM, we study 2D bidisperse systems, modeling polydispersity and jamming transitions. Employing the pebble game algorithm, we analyze rigidity percolation, particle contacts, and rheology to understand the formation of rigid clusters. Watch the talk here
Published:
Discontinuous shear thickening (DST) in suspensions occurs when stress drives particles into frictional contact networks, setting a threshold for shear-induced contacts. Using an established simulation technique [1], we show that contact networks grow with solid fraction and fluctuate under flow. As jamming nears, rigid clusters emerge with 2D Ising-like critical behavior. We analyze scaling in mono- and bidisperse suspensions (up to a 4:1 size ratio) and examine how shear and normal stresses relate to rigid structure formation.
Published:
The onset of shear thickening and, ultimately, jamming occurs due to the formation of large-scale microstructures within the suspension. Although these events are rare, they are significant enough to counterbalance the imposed shear stress in dense suspensions, leading to the development of frictional contact networks that resist further deformation.
Undergraduate Course, MR-103, CCNY, 2022
Welcome to Fall 2022! This course, ChE 43200: Chemical Reaction Engineering, this course covers reactor analysis and design for batch, flow, and semibatch reactors, along with homogeneous and heterogeneous reaction systems. Topics include catalysis, reaction mechanisms, heat and mass transfer effects, with applications in the chemical and petrochemical industries.
Undergraduate Course, NAC 1/203, CCNY, 2023
Welcome to Spring 2023! This course, ChE 22900: Chemical Thermodynamics, explores fundamental concepts in reaction engineering and thermodynamics, including thermodynamic laws, heat engines, steam turbines, and equations of state with phase equilibria.
Graduate Course, SH-203, CCNY, 2025
As part of the Engineering Analysis (Engr I1100) course, the computer project involves solving differential equations numerically using a programming language of choice (MATLAB is recommended).