Tag Archives: power stations

Thought leadership in fusion engineering

The harnessing of fusion energy has become something of a holy grail – sought after by many without much apparent progress.  It is the energy process that ‘powers’ the stars and if we could reproduce it on earth in a controlled environment then it would offer almost unlimited energy with very low environmental costs.  However, understanding the science is an enormous challenge and the engineering task to design, build and operate a fusion-fuelled power station is even greater.  The engineering difficulties originate from the combination of two factors: the emergent behaviour present in the complex system and that it has never been done before.  Engineering has achieved lots of firsts but usually through incremental development; however, with fusion energy it would appear that it will only work when all of the required conditions are present.  In other words, incremental development is not viable and we need everything ready before flicking the switch.  Not surprisingly, engineers are cautious about flicking switches when they are not sure what will happen.  Yet, the potential benefits of getting it right are huge; so, we would really like to do it.  Hence, the holy grail status: much sought after and offering infinite abundance.

Last week I joined the search, or at least offered guidance to those searching, by publishing an article in Royal Society Open Science on ‘An integrated digital framework for the design, build and operation of fusion power plants‘.  Working with colleagues at the Culham Centre for Fusion Energy, Richard Taylor and I have taken our earlier work on an integrated nuclear digital environment for the nuclear energy using fission [see ‘Enabling or disruptive technology for nuclear engineering?‘ on january 28th, 2015] and combined it with the hierarchical pyramid of testing and simulation used in the aerospace industry [see ‘Hierarchical modelling in engineering and biology‘ on March 14th, 2018] to create a framework that can be used to guide the exploration of large design domains using computational models within a distributed and collaborative community of engineers and scientists.  We hope it will shorten development times, reduce design and build costs, and improve credibility, operability, reliability and safety.  It is a long list of potential benefits for a relatively simple idea in a relatively short paper (only 12 pages).  Follow the link to find out more – it is an open access paper, so it’s free.

References

Patterson EA, Taylor RJ & Bankhead M, A framework for an integrated nuclear digital environment, Progress in Nuclear Energy, 87:97-103, 2016.

Patterson EA, Purdie S, Taylor RJ & Waldon C, An integrated digital framework for the design, build and operation of fusion power plants, Royal Society Open Science, 6(10):181847, 2019.

Digitally-enabled regulatory environment for fusion powerplants

Digital twins are a combination of computational models and real-world data describing the form, function and condition of a system [see ‘Can you trust your digital twin?‘ on November 23rd 2016]. They are beginning to transform design processes for complex systems in a number of industries.  We have been working on a proof-of-concept study for a digital reactor in fission energy based on the Integrated Nuclear Digital Environment (INDE) [1].  The research has been conducted by the Virtual Engineering Centre (VEC) at the University of Liverpool together with partners from industry and national laboratories with funding from the UK Government for nuclear innovation.  In parallel, I having been working with a colleague at the University of Manchester and partners at the Culham Centre for Fusion Energy on the form of a digital environment for fusion energy taking account of the higher order of complexity, the scale of resources, the integration of novel technologies, and the likely diversity and distribution of organisations involved in designing, building and operating a fusion powerplant.  We have had positive interactions with the regulatory authorities during the digital fission reactor project and the culture of enabling-regulation [2] offers an opportunity for a new paradigm in the regulation of fusion powerplants.  Hence, we propose in a new PhD project to investigate the potential provided by the integration of digital twins with the regulatory environment to enable innovation in the design of fusion powerplants.

The PhD project is fully-funded for UK and EU citizens as part of a Centre for Doctoral Training and will involve a year of specialist training followed by three years of research.  For more information following this link.

References:

[1] Patterson EA, Taylor RJ & Bankhead M, A framework for an integrated nuclear digital environment, Progress in Nuclear Energy, 87:97-103, 2016.

[2] http://www.onr.org.uk/documents/2018/guide-to-enabling-regulation-in-practice.pdf

Image: https://www.pexels.com/photo/diagram-drawing-electromagnetic-energy-326394/

Crack tip plasticity in reactor steels

Amplitude of temperature in steel due to a cyclic load with a crack growing from left to right along the horizontal centre line with the stress concentration at its tip exhibiting the peak values. The wedge shapes in the left corners are part of the system.

At this time of year the flow into my inbox is augmented daily by prospective PhD students sending me long emails describing how their skills, qualifications and interests perfectly match the needs of my research group, or sometimes someone else’s group if they have not been careful in setting up their mass mailing.  At the moment, I have four PhD projects for which I am looking for outstanding students; so, because it will help prospective students and might interest my other readers but also because I am short of ideas for the blog, I plan to describe one project per week for the next month.

The first project is about the effect of hydrogen on crack tip plasticity in reactor steels.  Fatigue cracks grow in steels by coalescing imperfections in the microstructure of the material until small voids are formed in areas of high stress.  When these voids connect together a crack is formed.  Repeated loading and unloading of the material provides the energy to move the imperfections, known as dislocations, and geometric features in structures are stress concentrators which focus this energy causing cracks to be formed in their vicinity.  The movement of dislocations causes permanent, or plastic deformation of the material.  The sharp geometry of a crack tip becomes a stress concentrator creating a plastic zone in which dislocations pile up and voids form allowing the crack to extend [see post on ‘Alan Arnold Griffith‘ on April 26th, 2017].  It is possible to detect the thermal energy released during plastic deformation using a technique known as thermoelastic stress analysis [see ‘Counting photons to measure stress‘ on November 18th 2015] as well as to measure the stress field associated with the propagating crack [1].  One of my current PhD students has been using this technique to investigate the effect of irradiation damage on the growth of cracks in stainless steel used in nuclear reactors.  We use an ion accelerator at the Dalton Cumbrian Facility to introduce radiation damage into specimens the size of a postage stamp and afterwards apply cyclic loads and watch the fatigue crack grow using our sensitive infra-red cameras.  We have found that the irradiation reduced the rate of crack growth and we will be publishing a paper on it shortly [and a PhD thesis].  In the new project, our industrial sponsors want us to explore the effect of hydrogen on crack growth in irradiated steel, because the presence of hydrogen is known to accelerate fatigue crack growth [2] which is believe to happen as a result of hydrogen atoms disrupting the formation of dislocations at the microscale and localising plasticity at crack tip on the mesoscale.  However, these ideas have not been demonstrated in experiments, so we plan to do this using thermoelastic stress analysis and to investigate the combined influence of hydrogen and irradiation by developing a process for pre-charging the steel specimens with hydrogen using an electrolytic cell and irradiating them using the ion accelerator.  Both hydrogen and radiation are present in a nuclear reactor and hence the results will be relevant to predicting the safe working life of nuclear reactors.

The PhD project is fully-funded for UK and EU citizens as part of a Centre for Doctoral Training and will involve a year of specialist training followed by three years of research.  For more information following this link.

References:

  1. Yang, Y., Crimp, M., Tomlinson, R.A., Patterson, E.A., 2012, Quantitative measurement of plastic strain field at a fatigue crack tip, Proc. R. Soc. A., 468(2144):2399-2415.
  2. Matsunaga, H., Takakuwa, O., Yamabe, J., & Matsuoka, S., 2017, Hydrogen-enhanced fatigue crack growth in steels and its frequency dependence. Phil. Trans. R. Soc. A, 375(2098), 20160412

Planetary Emergency

Global energy budget from Trenberth et al 2009

This week’s lecture in my thermodynamics course for first-year undergraduate students was about thermodynamic systems and the energy flows in and out of them. I concluded the lecture by talking about our planet as a thermodynamic system using the classic schematic in the thumbnail [see ‘Ample sufficiency of solar energy‘ on October 25th, 2017 for more discussion on this schematic].  This is usually a popular lecture but this year it had particular resonance because of the widely publicised strikes by students for action on climate change.  I have called before for individuals to take responsibility given the intransigence of governments [see ‘Are we all free riders‘ on June 6th, 2016 or ‘New Year Resolution‘ on December 31st, 2014]; so, it is good to see young people making their views and feelings known.

Weather-related events, such as widespread flooding and fires, are reported so frequently in the media that perhaps we have started to ignore them as portents of climate change.  For me, three headlines events have reinforced the gravity of the situation:

  1. The publication earlier this month of a joint report by UNICEF and the Royal College of Paediatrics and Child Health that air pollution in the UK so high that it is infringing the fundamental rights of children to grow up in a clean and safe environment; and, under the Government’s current plans, air pollution in the UK is expected to remain at dangerous levels for at least another 10 years.
  2. The warning earlier this month from the Meteorological Office in London that global warming could exceed 1.5C above pre-industrial levels within five years.  In my lecture, I highlighted that a 2C rise would be equal to the temperature 3 million years ago when sea levels were 25 to 35m high; and, a 1m rise in sea level would displace 145 million people globally [according to Blockstein & Weigmann, 2010].
  3. The suspension of construction of the new nuclear power station on Anglesey by Hitachi, which leaves the UK Government’s energy strategy in disarray with only one of the six planned new power stations under construction.  This leaves the UK unable to switch from fossil-fuelled to electric vehicles and dependent on fossil fuel to meet current electricity demand.

I apologise for my UK focus this week but whereever you are reading this blog you could probably find similar headlines in your region.  For instance, the 2016 UNICEF report states that one in seven children worldwide live in toxic air and air pollution is a major contributing factor in the deaths of around 600,000 children under five every year.  These three headlines illustrate that there is a planetary emergency because climate change is rapidly and radically altering the ecosystem with likely dire consequences for all living things; that despite a near-existential threat to the next generation as a consequence of air pollution most governments are effectively doing nothing; and that in the UK we are locked into a fossil-fuel dependency for the foreseeable future due to a lack of competent planning and commitment from the government which will compound the air pollution and climate change problems.

Our politicians need to stop arguing about borders and starting worrying about the whole planet.  We are all in this together and no man-made border will protect us from the impact of making the planet a hostile environment for life.