Working Party on Multi-scale Modelling of Fuels and Structural Materials for Nuclear Systems (WPMM)

The Working Party on Multi-scale Modelling of Fuels and Structural Material for Nuclear Systems (WPMM) was established in 2007 to deal with the scientific and engineering aspects of fuels and structural materials, aiming at establishing multi-scale models and simulations as validated predictive tools for the design of nuclear systems, fuel fabrication and performance. The WPMM’s objective was to promote the exchange of information on models and simulations of nuclear materials, theoretical and computational methods, experimental validation, and related topics. It also provided member countries with up-to-date information, shared data, models and expertise. The Working Party assessed nuclear modelling improvement needs and addressed these needs by initiating joint efforts. The WPMM reviewed and evaluated the multi-scale modelling and simulation techniques currently employed in the selection of materials used in nuclear systems. It also provided advice to the nuclear community on the developments needed to meet the requirements of modelling for the design of different nuclear systems.

The WPMM liaised closely with other NEA working groups, especially those operating under the guidance of the Nuclear Science Committee (NSC) in order to ensure the complementarity of the respective work programmes. Particularly close working relationships were maintained with the Working Party on Scientific Issues of Advanced Fuel Cycles (WPFC), the WPFC Expert Group on Innovative Fuel Elements (EGIFE), the WPFC Expert Group on Innovative Structural Materials (EGISM), the Expert Group on Accident-tolerant Fuels for Light Water Reactors (EGATFL), the  Expert Group on Multi-physics Experimental Data, Benchmarks and Validation (EGMPEBV), the Expert Group on Reactor Fuel Performance (EGRFP) and the NEA Project on Thermodynamics of Advanced Fuels International Database (TAF-ID).

The WPMM mandate ended in 2020, and the materials science activities are now carried out under the auspices of the Working Party on the Materials Science Issues in Nuclear Fuels and Structural Materials (WPFM).

Publications and reports
WPMM expert groups

The WPMM was structured into three areas of focus: general multiscale modelling methods, multiscale modelling of nuclear fuels and structural materials modelling.

WPMM organigram

WPMM members

WPMM working area (password protected | reminder)

Related external workshops and conferences

External publication

Tonks, M. et al., "Unit mechanisms of fission gas release: Current understanding and future needs", Journal of Nuclear Materials, vol. 504, June 2018, Elsevier, pp. 300-317, doi: