Deadline: Applications will be accepted at any time until the position is filled.
Many soils can be considered to be porous media.Â The amount of water contained within pore spaces in soils (often characterised in terms of moisture content) can have a large impact on the properties of the soil.Â Engineering behaviour characterised in terms of strength, stiffness, thermal conductivity and heat storage capacity all depend on soil moisture content. However, in many natural and engineered environments soil moisture content is not constant and will change as a result of imposed thermal gradients.Â These might be generated by buried electric cables, disposal of high level nuclear waste or the use of the ground as a storage medium for thermal energy. Therefore understanding how thermal gradients will affect soil moisture content is of increasing relevance in geotechnical engineering.
The process of moisture migration under thermal gradients is one of evaporation and re-condensation in different locations. This will cause drying near a heat source and wetting of outlying areas.Â Existing theories describing this process do not always capture real phenomena such as hysteresis of wetting and drying under cyclic conditions that would be experienced in the ground around heat pump systems. This PhD project will offer a unique opportunity to use CT scanning technology to observe moisture migration in porous media for the first time.Â Through experiments carried out within the scanners, the project aims to identify which types of soils are most susceptible to the processes of moisture migration and to quantify this effect.Â It will then be possible to examine the impacts of cycling thermal conditions on the moisture migration processes and the resulting engineering properties of the soils tested.
The research will feed into a larger project on ground heat storage funded by the Royal Academy of Engineering and will be supervised by Dr Loveridge, Professor Powrie, Dr Boardman and Professor Sinclair.Â
If you wish to discuss any details of the project informally, please contact Fleur Loveridge, Infrastructure research group, Email: [email protected], Tel: +44 (0) 2380 59 2662.