GERMÁN VARAS
Instituto de Física, Pontificia Universidad Católica de Valparaíso
Av. Universidad 330 (Curauma), Valparaiso, Chile.
Av. Universidad 330 (Curauma), Valparaiso, Chile.
Office: +56 32 2274889
Lab: +56 32 2274987
german.varas_at_pucv.cl
Interest in: Granular Materials - MultiphaseFlow - Nonlinear Physics
Lab: +56 32 2274987
german.varas_at_pucv.cl
Interest in: Granular Materials - MultiphaseFlow - Nonlinear Physics
Current Research
Crater Formation
Jets impacting on a solid obstacle or confined in a cavity can develop self-sustained oscillations. Do these oscillations arise when the jet impacts a porous medium? What is the coupling with crater morphology? The present work focuses on the stability of a liquid jet when impacting a confined saturated granular bed.
Free fall crater formation under microgravity conditions
Crater formation has been widely studied through different strategies. One of them consists on simplifying the problem to the impact of a spherical projectile on a granular layer. Due to technical limitations, experimental studies have focused independently on either the corolla formation or the deformation inside the granular bed. Hence, so far, it has not been possible to link these two processes. Here, we present an original experiment that allows to simultaneously observe the granular dynamics both above and below the granular layer in microgravity conditions.
Air invasion in water-saturated sand
We study and characterize pattern formation in immersed granular systems, when submitted to an ascending flow (gas or liquid). We are interested in the dynamics of the air-flow patterns under one or multiple injection points at the base (by imposing a constant pressure or flow-rate).
Geometry-controlled phase transitions in vibrated granular media
We explore the role of the geometry on a Hele-Shaw cell filled with grains. At constant energy we can transit from a solid or fluid modified only the boundary conditions.
Particle interactions
One particle under a granular bath behaves as if it were Brownian, will two or more particles do the same?. In this experiment we seek to see if there are (or not) interactions between two or more particles in a granular bath.
News!
Sand Sweeper Robot
We present the progress of our new project: The development of a vehicle for the efficient and autonomous collection of waste on beaches.
Cover of Granular Matter journal
Our article Geometrical description of impact cratering under microgravity conditions was selected as the cover of the journal Granular Matter (May 2022). You can review the article (and others) in the Publications section or directly on the website of Granula Matter.
