Drying of materials
PDR SecFiss – “Experimental and numerical study of cracking during the drying of porous materials: applications in the fields of chemical engineering and geomechanics”(FNRS PDR T.1094.14)
T
his project aims to improve our understanding of the mechanisms behind cracking/fracturing of porous deformable materials during convective drying or desiccation. It relies on an experimental as well as a modelling approach. Its originality lies in the collaboration between our team and the GEO3 team from the UEE department.
From an experimental standpoint, the study is based on the use of 3D images acquired by X-ray microtomography in order to characterise, during drying, local deformations and potential cracks. This requires the development of accurate and robust image analysis methods to highlight the links between microstructure, effective mechanical properties, and crack susceptibility. The GEO3 group will focus on clay rocks, and the behaviour of geomaterials under forced flow circulation in the context of nuclear waste disposal in excavated damage zones. In the PEPs group, tests will be performed on resorcinol-formol resins, following previous works in a 'product engineering' approach. The objective is to establish a link between manufacturing parameters, microstructure, drying and product final quality, defined by the absence of cracks. From a modelling point of view, constitutive laws must first be established, in order to incorporate cracking phenomena in the thermo-hydro-mechanical models developed in the finite element LAGAMINE code. To numerically reproduce the cracking in a robust and accurate way, different options will be considered, such as using higher order finite elements or specific interpolation functions, as well as XFEM.
Some other current projects :
- BIOSOLIDS : Optimization of sludge dewatering and drying through a better understanding of its rheological characteristics and evolution within the whole treatment chain - Sergio Luis PARRA ANGARITA (PEPs Group)
- FRIA (Funding by Walloon Region) : Contribution au développement d'un procédé "low cost" de stabilisation des boues d'épuration - Hajer BEN HAMED (PEPs Group)
- SWAM@ASC (FEDER) : Smart Water Management Across Scales - Development of electrocoagulation for phosphorus recovering in waste waters and biomethanisation with sludges for SMEs - Pierre NGUE SONG (NCE Group)
Publications
J. Hubert, N. Prime, E. Plougonven, A. Léonard, and F. Collin. Desiccation cracks formation in clay-barrier for nuclear waste disposal. Geotechnical & Structures Engineering Congress, February 2016. Phoenix Arizona, USA.
E. Plougonven, J. Hubert, N. Prime, F. Collin, and A. Léonard. Accurate measurement of radius evolution as a function of direction in 3D images. Micro-CT User Meeting, May 2016. Mondorf, Luxemburg.