Blog posts

I have an opening for a new postdoc to join my research group. The project is on the field-scale calibration of DEM models. Primary responsibilities include developing and executing large-scale experiments, interpretation and synthesis of results, and collaboration with modelers to perform the calibrations.

Lotus leaves floating on water usually experience short-wavelength edge wrinkling that decays toward the center, while the leaves growing above water normally morph into a global bending cone shape with long rippled waves near the edge. Observations suggest that the underlying water (liquid substrate) significantly affects the morphogenesis of leaves.

H. Hou, E. Simsek, T. Ma, N.S. Johnson, S. Qian, C. Cissé, D. Stasak, N. Al Hasan, L. Zhou, Y. Hwang, R. Radermacher, V.I. Levitas, M.J. Kramer, M. Asle Zaeem, A.P. Stebner, R.T. Ott, J. Cui, I. Takeuchi. Fatigue-resistant high-performance elastocaloric materials made by additive manufacturing. Science 366 (6469) (2019) 1116-1121.

Abstract

Adhesive contact of the Hertzian indenter with an incompressible elastic substrate bi-directionally stretched along the indenter principal planes of curvature is considered in the Johnson–Kendall–Roberts theoretical framework. An approximate model is constructed by examining energy release rate conditions only on the edges of the minor and major axes of the contact ellipse. The effect of weak coupling between fracture modes I and II is introduced using a phenomenological mode-mixity function.