Typically, in quiescent conditions, attractive colloids at low volume fractions form fractal gels structured into two length scales: the colloidal and cluster scales. However, when flow interferes with gelation gels, it may display three distinct scales [Dagès et al., Soft Matter 18, 6645–6659 (2022)]. Following those recent experimental investigations, we derive models that account for structure rheological properties of such atypical gels. The gel elasticity is inferred from scaling...

Colloidal gels are out-of-equilibrium soft solids composed of attractive Brownian particles that form a space-spanning network at low volume fractions. The elastic properties these systems result from the microstructure, which is very sensitive to shear history. Here, we take advantage such sensitivity tune viscoelastic colloidal gel made carbon black nanoparticles. Starting fluidized state an applied rate 0, use abrupt flow cessation trigger liquid-to-solid transition. We observe resulting...

The rheological behavior of colloidal dispersions is paramount importance in a wide range applications, including construction materials, energy storage systems, and food industry products. These consistently exhibit non-Newtonian behaviors, consequence intricate interplays involving colloids morphology, volume fraction, interparticle forces. Understanding how structure under flow remains challenge, particularly the presence attractive forces leading to cluster formation. In this study, we...

Colloidal suspensions and the relation between their rheology microstructure are investigated. The literature showed great evidence of rheological quantities particle volume fraction, ignoring influence cluster. We propose to extend previous models using a new double fractal structure which allows, first, recover well-known on case percolated system and, second, capture cluster size. This model emphasizes necessity such account for recent experimental results. Then, is compared with data...

Aggregation and disaggregation of clusters attractive particles under flow are studied highlight the growth average steady-state cluster size as a power law adhesion number, dimensionless number that quantifies ratio forces to shear stress. Such power-law scaling results from competition between aggregation processes, previously reported. Here we rationalize this behavior through model based on an energy function, for which minimization yields exponent in terms fractal dimension, good...

Despite many years of research about the comprehension fluid-dynamic related phenomena and improvements in performance cold spray systems, ensuring high fidelity simulations gas particle flow remains a challenge. In this work, detailed modeling, namely, improved delayed detached eddy simulation, axisymmetric geometries was proposed compared with more usual numerical framework, Reynolds averaged Navier–Stokes model. After its validation against literature data three different nozzle...

The rheological behavior of colloidal dispersions is paramount importance in a wide range applications, including construction materials, energy storage systems and food industry products. These consistently exhibit non-Newtonian behaviors, consequence intricate interplays involving colloids morphology, volume fraction, inter-particle forces. Understanding how structure under flow remains challenge, particularly the presence attractive forces leading to clusters formation. In this study, we...

Cold spray technology is a quickly growing manufacturing which impacts lots of industries. Despite many years studies about the comprehension phenomena and improvements performance system, ensuring high fidelity simulations remains challenge. We propose in this work detailed modeling giving more insight appearing cold such as turbulence, oblique shocks, bow fluctuations, particles motion impacts. It mainly based on richer model known Detached Eddy Simulation (DES) model. Moreover, we present...

Colloidal gels are out of equilibrium soft solids composed attractive Brownian particles that form a space-spanning network at low volume fractions. The elastic properties these systems result from the microstructure, which is very sensitive to shear history. Here, we take advantage such sensitivity tune viscoelastic colloidal gel made carbon black nanoparticles. Starting fluidized state under an applied rate $\dot γ_0$, use abrupt flow cessation trigger liquid-to-solid transition. We...

Aggregation and disaggregation of clusters attractive particles under flow are studied from numerical theoretical points view. Two-dimensional molecular dynamics simulations both Couette Poiseuille flows highlight the growth average steady-state cluster size as a power law adhesion number, dimensionless number that quantifies ratio forces to shear stress. Such power-law scaling results competition between aggregation processes, already reported in literature. Here, we rationalize this...

Typically, in quiescent conditions, attractive colloids at low volume fractions form fractal gels structured into two length scales: the colloidal and cluster scales. However when flow interfere with gelation may display three distinct scales [Dagès, et al., Soft Matter 18, 6645 (2022)]. Following those recent experimental investigations, we derive models that account for structure rheological properties of such atypical gels. The gel elasticity is inferred from scaling arguments translated...