We are seeking a full time PhD researcher with interests in granular physics, geomechanics, computer modelling and the discrete element methods (DEM) to join University of Twente (Netherlands) and work on micro- and meso-scale modelling to understand the initiation and dynamics of submarine landslides.
This project is part of the EU funded Marie Curie Doctoral Network POSEIDON – Improve offshore infrastructure resilience against geohazards towards a changing climate (www.poseidon-dn.eu). The overarching objective of POSEIDON is to develop solutions to improve the resilience of offshore infrastructures. POSEIDON will train 13 researchers within a collaborative multidisciplinary and inter-sectorial network involving 9 universities, 3 research institutes and 4 industrial partners across Europe.

Background and aim:
Hydromechanical phenomena at the pore scale, such as the development of elevated water pressure, and how they are coupled to the soil’s mesostructure, are key to the initiation and runout of submarine landslides. The fact that different regimes, e.g., quasi-static or fast-flowing, of the coupled particle-fluid systems interplay with the material’s particle- and meso-scale structures makes the prediction of submarine granular flows, from initiation to run-out, a scientific as well as a practical challenge.

Fully-resolved simulations of particle-fluid systems can be used to study the macroscopic behaviour of saturated granular materials. The effects of particle shapes and the mesostructure on the hydrodynamic coupling to the pore fluid can all be investigated with the coupled Lattice Boltzmann-Discrete Element Method.

We aim to develop a hydro-micromechanical model of realistic granular soils using fully-resolved direct numerical simulation techniques, focusing on representative volume elements (RVEs). The goal is to understand the role of grain morphology and mesostructure in the avalanching and resting processes during submarine landslides, at various overpressure conditions.

Objectives:
i) Apply an existing LBM-DEM numerical model to simulate the collapse of dense/loose granular masses over an inclined plane subjected to sudden increase of pore pressure;

ii) Incorporate realistic particle shapes in the LBM-DEM model and study the effect of grain morphology hydromechanical behaviour at NGI;

iii) Compare and validate the simulations at point i) and ii) with the pilot-scale laboratory experiments on granular–liquid mixtures at the Free University of Bolzano;

iv) Coarse grain particle scale information into continuum fields and understand the mass/momentum transfer and energy dissipation mechanisms that contribute to the triggering and runout of saturated granular flows.

Expected Results:
i) A novel hydro-micromechanical numerical tool for modelling saturated granular masses in submarine landslides;

ii) A deep understanding of the interplay between structural properties (e.g., morphology and mesostructure) and pore water pressure on the saturated granular flows.

Planned Secondment(s):
Dr. Nallathamby Sivasithamparam (NGI, 6 months): integrate particle shape within LBM-DEM.

Dr. Michele Larcher (Free University of Bolzano, 3 months): perform experiments in the inclined channel experimental device on dense/loose granular slopes and compare with simulations.

• Obtained a MSc degree in a relevant field such as civil engineering, mechanical engineering, computational physics, applied mathematics, materials science, or related areas;
• Good knowledge of fluid-coupled particulate systems in slow and/or fast motion;
• Sound programming skills in C/C++, Fortran, Python or equivalent;
• Experience with the discrete element method or other particle-based numerical methods would be advantageous;
• You are an excellent teammate, able to collaborate intensively with industrial and academic parties in regular meetings and work visits;
• An appropriate qualification in the English Language together with excellent communication and organizational skills
• We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, or disability status. Women are encouraged to apply for this position. This is part of the University of Twente’s strategy toward a diverse and inclusive working environment, supportive of excellence in research and education.

We offer you a very exciting position in an inspiring multidisciplinary environment. The university offers a dynamic ecosystem with enthusiastic colleagues in which internationalization is an important part of the strategic agenda.

• We offer a full-time 4-year PhD-position, with excellent mentorship and a stimulating research environment.
• Collaborations with a dedicated, dynamic research team and external parties from several European countries involved in the POSEIDON project.
• The gross monthly salary will be ranging from € 2.770,00 (first year), increasing each year up to € 3.539,00 in the fourth year. Salary and associated conditions are in accordance with the collective labour agreement for Dutch universities (CAO-NU).
• You will have a minimum of 232 leave hours in case of full-time employment based on a formal workweek of 38 hours.
• A full-time employment in practice means 40 hours a week, therefore resulting in 96 extra leave hours on an annual basis.
• We offer excellent fringe benefits including a holiday allowance of 8% of the gross annual salary, an end-of-year bonus of 8.3%, a solid pension scheme, free access to sports facilities and a family-friendly institution that offers parental leave (both paid and unpaid).
• The University of Twente is situated on a green and lively campus with lots of facilities for sports and other activities.