Tag Archives: nuclear energy

Opportunities lost in knowledge management using digital technology

Decorative imageRegular readers of this blog will know that I occasionally feature publications from my research group.  The most recent was ‘Predicting release rates of hydrogen from stainless steel’ on September 13th, 2023 and before that ‘Label-free real-tracking of individual bacterium’ on January 25th 2023 and ‘A thermal emissions-based real-time monitoring system for in situ detection of cracks’ in ‘Seeing small changes is a big achievement’ on October 26th 2023.  The subject of these publications might seem a long way apart but they are linked by my interest in trying to measure events in the real-world and use the data to develop and validate high-fidelity digital models.  Recently, I have stretched my research interests still further through supervising a clutch of PhD students with a relatively new collaborator working in the social sciences.  Two of the students have had their first papers published by the ASME (American Society of Mechanical Engineers) and the IEEE (Institute of Electrical and Electronics Engineers).  Their papers are not directly connected but they both explore the use of published information to gain new insights on a topic.  In the first one [1], we have explored the similarities and differences between safety cases for three nuclear reactors: a pair of research reactors – one fission and one fusion reactor; and a commercial fission reactor.  We have developed a graphical representation of the safety features in the reactors and their relationships to the fundamental safety principles set out by the nuclear regulators. This has allowed us to gain a better understanding of the hazard profiles of fission and fusion reactors that could be used to create the safety case for a commercial fusion reactor.  Fundamentally, this paper is about exploiting existing knowledge and looking at it in a new way to gain fresh insights, which we did manually rather than automating the process using digital technology.  In the second paper [2], we have explored the extent to which digital technologies are being used to create, collate and curate knowledge during and beyond the life-cycle of an engineering product.  We found that these processes were happening but generally not in a holistic manner.  Consequently, opportunities were being lost through not deploying digital technology in knowledge management to undertake multiple roles simultaneously, e.g., acting as repositories, transactive memory systems (group-level knowledge sharing), communication spaces, boundary objects (contact points between multiple disciplines, systems or worlds) and non-human actors.  There are significant challenges, as well as competitive advantages and organisational value to be gained, in deploying digital technology in holistic approaches to knowledge management.  However, despite the rapid advances in machine learning and artificial intelligence [see ‘Update on position of AI on hype curve: it cannot dream’ on July 26th 2023] that will certainly accelerate and enhance knowledge management in a digital environment, a human is still required to realise the value of the knowledge and use it creatively.

References

  1. Nguyen, T., Patterson, E.A., Taylor, R.J., Tseng, Y.S. and Waldon, C., 2023. Comparative maps of safety features for fission and fusion reactors. Journal of Nuclear Engineering and Radiation Science, pp.1-24
  2. Yao, Y., Patterson, E.A. and Taylor, R.J., 2023. The Influence of Digital Technologies on Knowledge Management in Engineering: A Systematic Literature Review. IEEE Transactions on Knowledge and Data Engineering.

Inconvenient data about electricity generation

Decorative infographicI like a good infographic and this one showing annual energy flows for a country  is one of my favourites [see ‘Energy blending’ on May 22nd 2013].  Some governments produce them annually.  The image shows the latest one for the UK [2021]. It makes interesting but perhaps depressing reading.  Transportation using fossil fuels accounts for 31% (41.6/134.1 million tonnes oil equivalent) of the UK energy consumption while electricity output accounts for only 21% (28.6/134.1 million tonnes oil equivalent).  This implies that if all vehicles were powered by electricity then the output of our power stations would need to increase to 70.2 million tonnes oil equivalent or between two- and three-fold (excluding conversion & transmission losses).  You can perform a similar analysis for the USA [see 2021 Energy flow chart from LLNL].  Fossil-fuelled transportation accounted for 25%  (24.3/97.3 Quads) and electricity output 13% (12.9/97.3 Quads) so converting all transportation to be electrically powered requires a three-fold increase in electrical output from power stations. It is more difficult to find equivalent data for Japan; however, in 2014 [see Energy flow chart from I2CNER Kyushu University] fossil-fuelled transportation accounted for 32% (3.03/9.52 EJ) and electricity output 38% (3.66/9.52 EJ) so converting all transportation to be electrically powered requires a two-fold increase in electrical output from power stations.  None of the above takes account of space heating mainly via fossil fuel or that many existing power stations are fossil-fuelled and need to be replaced in order to achieve net zero carbon emissions.  Hence, the required scale of construction of power stations using renewable sources, including nuclear, solar and wind, is enormous and in most countries it is barely discussed let alone planned or started; leading to the conclusion that there is little chance of achieving net zero carbon emissions by 2050 as called for by the Paris agreement.

Predicting release rates of hydrogen from stainless steel

Decorative photograph showing electrolysis cellThe influence of hydrogen on the structural integrity of nuclear power plant, where water molecules in the coolant circuit can be split by electrolysis or radiolysis to produce hydrogen, has been a concern to engineers for decades.  However, plans for a hydrogen economy and commercial fusion reactors, in which plasma-facing structural components will likely be exposed to hydrogen, has accelerated interest in understanding the complex interactions of hydrogen with metals, especially in the presence of irradiation.  A key step in advancing our understanding of these interactions is the measurement and prediction of the uptake and release of hydrogen by key structural materials.  We have recently published a study in Scientific Reports in which we developed a method for predicting the amount hydrogen in a steel under test conditions.  We used a sample of stainless steel as an electrode (cathode) in an electrolysis cell that split water molecules producing hydrogen atoms that were attracted to the steel. After loading the steel with hydrogen in the cell, we measured the rate of release of the hydrogen from the steel over two minutes by monitoring the drop in current in the cell, using a technique called potentiostatic discharge.  We used our measurements to calibrate a model of hydrogen release rate, based on Fick’s second law of diffusion, which relates the rate of hydrogen motion (diffusion) to the surface area perpendicular to the motion and the concentration gradient in the direction of motion.  Finally, we used our calibrated model to predict the release rate of hydrogen over 24 hours and checked our predictions using a second measurement based on the hydrogen released when the steel was melted.  So, now we have a method of predicting the amount of hydrogen in a steel remaining in a sample many hours after exposure during electrolysis without destroying the test sample.  This will allow us to perform better defined tests on the influence of hydrogen on the performance of stainless steel in the extreme environments of fission and fusion reactors.

Source:

Weihrauch M, Patel M, Patterson EA. Measurements and predictions of diffusible hydrogen escape and absorption in cathodically charged 316LN austenitic stainless steel. Scientific Reports. 13(1):10545, 2023.

Image:

Figure 2a from Weihrauch et al , 2023 showing electrolysis cell setup for potentiostatic discharge experiments.

Reliable predictions of non-Newtonian flows of sludge

Regular readers of this blog will be aware that I have been working for many years on validation processes for computational models of structures employed in a wide range of sectors, including aerospace engineering [see ‘The blind leading the blind’ on May 27th, 2020] and nuclear energy [see ‘Million to one’ on November 21st, 2018].  Validation is determining the extent to which predictions from a model are representative of behaviour in the real-world [see ‘Model validation’ on September 18th, 2012].  More recently, I have been working on model credibility, which is the willingness of people, besides the modeller, to use the predictions from models in decision-making [see, for example, ‘Credible predictions for regulatory decision-making’ on December 9th, 2020].  I have started to consider the complex world of predictive modelling of fluid flow and I am hoping to start a collaboration with a new colleague on the flow of sludges.  Sludges are more common than you might think but we are interested in modelling the flow of waste, both wastewater (sewage) and nuclear wastes.  We have a PhD studentship available sponsored jointly by the GREEN CDT and the National Nuclear Laboratory.  The project is interdisciplinary in two dimensions because it will combine experiments and simulations as well as uniting ideas from solid mechanics and fluid mechanics.  The integration of concepts and technologies across these boundaries brings a level of adventure to the project which will be countered by building on well-established research in solid mechanics on quantitative comparisons of measurements and predictions and by employing current numerical and experimental work on wastewater sludges.  If you are interested or know someone who might want to join our research then you can find out more here.

Image: Sewage sludge disposal in Germany: Andrea Roskosch / UBA