research

We formulate a geometric nonlinear theory of the mechanics of accretion. In this theory the reference configuration of an accreting body is represented by a time-dependent Riemannian manifold with a time-independent metric that at each point depends on the state of deformation at that point at its time of attachment to the body, and on the way the new material is added to the body. We study the incompatibilities induced by accretion through the analysis of the material metric and its curvature in relation to the foliated structure of the accreted body.

Project title: Dynamics of methane bubbles ascent in fine-grained aquatic sediments. The project implies conducting modeling and simulations in the field of solid mechanics/linear elastic fracture mechanics.

This study aims at:

• analyzing dynamics and controlling factors of methanebubble ascent toward the seaflooraccompanied by fracturing of the ambient solid sediment;

• estimation of possibility of methane (a greenhouse gas) release to the water column and to the atmosphere;

Owing to their enormous capacities, Li-S batteries have emerged as a prime candidate for economic and sustainable energy storage. Still, potential mechanics-based issues exist that must be addressed: lithiation of sulfur produces an enormous volume expansion (~80%). In other high capacity electrodes, large expansions generate considerable stresses that can lead to mechanical damage and capacity fading.

At workshop 

Computational Methods for Interface Problems Workshop

at UCL, organised by Erik Burman and colleagues

https://www.ucl.ac.uk/maths/events/2019/jan/computational-methods-interface-problems-workshop

Presentation download:

http://orbilu.uni.lu/handle/10993/37921

Liu, M., Suo, S., Wu, J., Gan, Y., Hanaor, D. A. H., & Chen, C. Q. Journal of Colloid and Interface Science, 2019, 539: 379-387. https://www.sciencedirect.com/science/article/pii/S0021979718315108#f00…

Hypothesis

In this paper, we experimentally characterize a simple and unified power law for the profiles of a variety of nanobubbles and nanotents formed by 2D materials such as graphene and MoS2 layers. https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.121.266101

ABSTRACT

Wide-ranging and multiple-revolution perturbed Lambert’s problems are building blocks for practical missions such as development of cislunar space, interplanetary navigation, orbital rendezvous, etc. However, it is of a great challenge to solve these problems both accurately and efficiently, considering the long transfer time and the complexity of high-fidelity modeling of space environment. For that, a methodology combining Optimal-Feedback Accelerated Picard Iteration methods and Fish-Scale Growing Method is demonstrated.

Investigations on the fast capacity loss of Lithium-ion batteries (LIBs) have highlighted a rich field of mechanical phenomena occurring during charging/discharging cycles, to name only a few, large deformations coupled with nonlinear elasticity, plastification, fracture, anisotropy, structural instability, and phase separation phenomena. In the last decade, numerous experimental and theoretical studies have been conducted to investigate and model these phenomena.

Wrinkles are commonly observed in uniaxially stretched rectangular sheets with clamped-clamped boundaries, and can disappear upon excess stretching. Here we explore this wrinkling and restabilization behavior both analytically and numerically. We find that Poisson’s ratio plays a crucial role in the wrinkling and restabilization behavior. Smaller Poisson’s ratio makes later onset of wrinkling, lower amplitude and earlier disappearance of wrinkles.