Humidity and heat transfers in hemp concrete

21 Mar 2024
Job Information

Organisation/Company

Université Gustave Eiffel

Research Field

Engineering

Researcher Profile

Recognised Researcher (R2)
Leading Researcher (R4)
First Stage Researcher (R1)
Established Researcher (R3)

Country

France

Application Deadline

14 Jun 2024 - 22:00 (UTC)

Type of Contract

Temporary

Job Status

Full-time

Offer Starting Date

1 Oct 2024

Is the job funded through the EU Research Framework Programme?

Not funded by an EU programme

Is the Job related to staff position within a Research Infrastructure?

No

Offer Description

Bio-based construction materials are systems containing or formed of vegetal particles, such as wood, hemp, cellulose, flax, cotton, etc., possibly linked with a mineral paste or an organic binder. They represent a promising solution for carbon emission reduction, due to their low production cost and their partial or full recyclability. Moreover, they bring more comfort to the occupants thanks to their moisture-buffering capacity, and they require less energy for heating or cooling. These qualities are obtained through exchanges between water vapor and “bound water”, i.e., water absorbed in the solid structure, combined with heat transfers. Consequently, understanding and predicting water and heat (hygrothermal) transfers in such materials is essential to selecting them appropriately, adjusting their conditions of use, and designing innovative materials. However, the current analysis of their performance is generally based on limited evaluations at a global scale or via macroscopic models lacking physical information. Our group has recently developed original approaches and tools that allow to clarify and quantify the internal heat and mass transfers thanks to a proper description of boundary conditions, along with new NMR and MRI techniques [1-4] providing spatially and temporally resolved distributions of the water in its different phases. The humidity and heat transfers are then observed and quantified in the form of a transport component in the solid (fiber) network, a transport component in the voids (between fibers), and a term of exchange (sorption-desorption) between the two phases [5].

The objective of this PhD work is to explore the possible extension of such an approach to biobased construction walls made of a mixture of natural fibers and a mineral paste, such as hemp concrete. This will be carried out with the help of model materials (e.g. cellulose + clay paste) and real material (hemp fibers of controlled size + lime paste). The humidity and heat transfers will be studied with macroscopic sorption or desorption tests, NMR and MRI measurements, heat transfer tests under steady or transient conditions, and modelled by diffusion processes. The objectives are to develop a relevant predictive model of heat and humidity transfers in fibers + mineral paste systems, to optimize the material choice in practice and control hygrothermal properties of biobased walls in buidlings for a reduction of energy consumption.

This work will be carried in Laboratoire Navier, within the framework of the ERC Advanced Grant PHYSBIOMAT (2023-2028), in collaboration with the Laboratory CPDM of University Gustave Eiffel. The candidate will thus benefit of a very favorable work environment within a group of research including various students or researchers experts in the different experimental or theoretical aspects of the project, along with all equipments for material characterization and physical observations.

Gross salary: 2420 euros per month. Start date: September or October 2024. Supervisor: Philippe Coussot

References:

[1] Maillet et al., Langmuir, 38, 15009−15025 (2022)

[2] Zhou et al., Physical Review Research, 1, 033190 (2019)

[3] Cocusse et al., Science Advances, 8, eabm7830 (2022)

[4] Zou et al., Cellulose, 30, 7463–7478 (2023)

[5] Zou et al., PNAS Nexus, 3, pgad450 (2024)

Funding category: Financement de l'Union européenne
ERC Advanced grant
PHD title: Doctorat de physique
PHD Country: France

Requirements
Specific Requirements

Skills: The candidate is expected to have a solid background in chemical or material engineering, and a strong motivation for research.

 

Note: Only candidates having obtained their Master's degree during the academic year before the starting date will be considered.

 

Additional Information
Work Location(s)

Number of offers available

1

Company/Institute

Université Gustave Eiffel

Country

France

City

Champs sur Marne

Geofield

Where to apply

Website

https://www.abg.asso.fr/fr/candidatOffres/show/id_offre/121484

Contact

Website

https://www.univ-gustave-eiffel.fr/

STATUS: EXPIRED