Month: January 2015

Enabling or disruptive technology for nuclear engineering?

INDEA couple of weeks ago [see ‘Small is beautiful and affordable in nuclear power-stations’  on January 14th, 2015] I ranted about the need to develop small modular reactors whose components can be mass-produced in a similar way to the wings, cockpit, tail-planes, fuselage and engines of an Airbus aeroplane that are manufactured in factories in different countries in Europe prior to final assembly and commissioning in Toulouse, France. The aerospace industry is heavily dependent on computer-aided engineering to design, test, manufacture, operate and maintain aircraft in a series of processes involving a huge number of organisations. The civil engineering and building services industries are following the same model through the introduction of BIM, or Building Information Modelling. I have recently suggested that the nuclear industry needs to adopt the same approach through an Integrated Nuclear Digital Environment (INDE) that has the potential to reduce operating and decommissioning costs and increase reliability and safety for existing and planned power-stations but more importantly would enable a move towards mass-production of modular power-stations.

Recently I presented a paper at a NAFEMS seminar on Modelling and Simulation in the Nuclear Industry held on November 19th 2014 in Manchester, UK.  To judge from the Q&A session afterwards, the paper divided the audience into those who could see the enormous potential (the enablers?) and those who saw only massive problems that rendered it unworkable (the potentially disrupted?). The latter group tends to cite the special circumstances of the nuclear industry associated with its risks and regulatory environment. These are important factors but are not unique to the industry. From my perspective of working with many other industrial sectors, the nuclear industry is unique in its slow progress in exploiting the potential of digital technologies.  Perhaps in the end, as one of my academic colleagues believes, research on solar power will produce such efficient solar cells that even in cold and cloudy England we will be able to meet all of our power needs from solar energy [given incoming solar radiation is about 340 Watts/square meter], in which case perhaps the nuclear power industry will become extinct unless it has evolved.

Schematic diagram showing the digital environment (second column from left in purple), its relationships to the real-world (left column in red) and the potential added value (third column from left) together with exemplar applications (right column). Coloured arrows are processes and coloured boxes represent physical (red) or digital (purple) infrastructure.

Schematic diagram showing the digital environment (second column from left in purple), its relationships to the real-world (left column in red) and the potential added value (third column from left) together with exemplar applications (right column). Coloured arrows are processes and coloured boxes represent physical (red) or digital (purple) infrastructure [from Patterson & Taylor, 2014].

The diagram is an extract from Patterson & Taylor, 2014.  The views expressed in this blog post are those of the author and not necessarily of those of his co-authors on other publications, or their employers.

Six NYC subway trains

Distribution of blog visitors in 2014

Distribution of blog visitors in 2014 (from

It would take six New York City subway trains to hold the number of visitors to this blog last year, according the Annual Report sent to me by  That’s more than double the number of visitors in 2013 which is quite an impressive increase.  The visitors came from more 100 countries which makes it a truly global blog, unless I have some globe-trotting readers who visited all of those countries between them during 2014.

The blog is also being published on Tumblr now, which my youngest daughter told me would be a waste of time because users of Tumblr are not interested in the sort of things I write about. However, an original objective of the blog was to increase public understanding of engineering and so this is small step to reach a wider public.

I wrote 54 posts last year so that there are more 120 posts in the archive now of which the five most frequently read are, in descending order:

Closed systems in nature? published on December 21st, 2012

100 Everyday engineering examples published on April 23rd, 2014

Small is beautiful published on October 10th, 2012

Benford’s law published on August 15th, 2014

Zen and entropy published on December 11th, 2013

If you only started reading the blog recently or you are visiting for the first time then you might enjoy some these old favourites.

Small is beautiful and affordable in nuclear power-stations

Most of you will have domestic carbon footprints that are similar to mine, i.e. dominated by energy consumption, probably mainly your car and climate control in your home, and you will struggle to reduce your footprint [see my post entitled ‘New Year Resolution’ on December 31st, 2014]. We live in a fossil fuel economy and so even if you make your home entirely powered by electricity and buy a plug-in car then your utility provider is still very likely to use fossil fuel to generate the electricity supplied to you and your carbon emissions will have been simply moved elsewhere. If you are lucky enough to live in a suitable location then installing geothermal, solar or wind power for your home might be viable; but otherwise the majority of us are dependent on power-stations for our electricity.

I discussed the impossibility, with today’s technology, of providing all of our electrical power needs using renewable sources in my post entitled ‘Energy Blending‘ on May 22nd, 2013. The alternatives are either to reduce our power consumption dramatically, which seems unlikely to happen given that everyone would like to enjoy the lifestyle of typical readers of blogs, or to build a very large number of nuclear power stations.  The scale of the problem facing China was the topic of my post entitled ‘Mass-produced nuclear power plants‘ on November 12th, 2014 and it is many times large on a global scale.

A major obstacle to building nuclear power-stations is their exorbitant capital cost, e.g. £24 billion for the planned Hinckley Point C reactor in the UK. This level of investment is beyond the reach of most companies and the construction of a fleet of such power-stations to provide national needs is beyond the budget of most national governments. Small modular reactors (SMR), whose components could be mass-produced and assembled on-site, have been proposed and both their small size and the manufacturing approach would lead to considerable reductions in unit costs. Although many designs for SMRs are under development, with mature designs in China and India, progress towards implementation and mass-production is slow so that the situation is ripe for a disruptive technology from another industrial sector to transform the nuclear power landscape. One possible candidate is the fusion reactor being developed by Lockheed Martin’s Skunk works [see my post entitled ‘Mass-produced nuclear power plants‘ on November 12th, 2014] or the Travelling Wave Reactor being developed by the spin-out company TerraPower.

We need to think big about small affordable solutions instead of thinking and spending big money on massive projects that tend towards a big unaffordable solution.

Also see Bill Gates on Energy-Miracles

Cow bladders led to modern strain measurement


softball figureSir David Brewster was a prolific experimentalist who published seven papers in the Philosophical Transactions of the Royal Society during 1815 and 1816. In his report dated October 22nd, 1814 that was published by the Royal Society one hundred years ago in January 1815, he described his observations on the depolarisation in more than fifty materials as diverse as sulphur and the bladder of a cow. He followed this with a series of experiments on glass sheets subject to various loads and reported his observations in the of photographic plates that show photoelastic fringe patterns which would become instantly recognisable to generations of engineers. Two hundred year later, digital technology has revolutionised photoelasticity so that it is no longer necessary to generate fringes that can be ‘seen’, as in Brewster’s experiments. Instead, digital sensors allow us to measure changes in light intensity that are undetectable to the naked eye and digital computers permit the processing of arrays of tens of thousands of measurements in less than the blink of an eye to yield maps of strain magnitude and direction in complex components. However, the principles employed in digital photoelasticity are the same as those first elucidated by Brewster and involve collecting images at multiple rotational steps of one or more of the polarising elements in a polariscope and then using Fourier analysis or matrix algebra to solve the equations describing the stress-optic law, i.e. the relationship between the applied stress and the observed change in transmitted light intensity. A polariscope is the term given to the series of polarisers and quarter-waveplates used by almost every photoelastician since Brewster to observe photoelastic fringes. One of Brewster’s other great inventions was the kaleidoscope of which there is an early example in the Science Museum in London. Recently, the concept of the kaleidoscope has been combined with a polariscope to create the poleidoscope that allows the multiple images required for digital photoelasticity to be acquired simultaneously, which is useful for dynamic applications such as in the impact example shown in the picture. These advances allow digital photoelasticity to be used not only by laboratory-based stress analysts but also in quality assurance procedures, for instance to monitor in real-time the stresses induced in float glass during production, or to investigate the residual stress in silicon wafers using infra-red light.

The picture shows a sequence of maps of photoelastic fringe order (right) showing the stress induced in an epoxy resin block when impacted by a soft ball falling under gravity (left). The maps were obtained using a precursor to the poleidoscope and a high-speed digital camera recording 4000 frames per second for the 10x10mm area shown by the white box in the schematic.

For more a little more on photoelasticity see


Brewster, D., Experiments on the depolarisation of light as exhibited by various mineral, animal , and vegetable bodies, with a reference of the phenomena to the general principles of polarisation, Phil. Trans. R. Soc. Lond. 105:29-53, 1815.

Brewster, D., On the communication of the structure of doubly refracting crystals to glass, muriate of soda, fluor spar, and other substances by mechanical compression and dilatation, Phil. Trans. R. Soc. Lond. 106:156-178, 1816.

Ramesh, K., Kasimayan, T., Neethi Simon, B., Digital photoelasticity – a comprehensive review, J. Strain Analysis, 46(4):245-266, 2011.

Lesniak, J.R., Zhang, S.J., Patterson, E.A., The design and evaluation of the poleidoscope: a novel digital polariscope, Experimental Mechanics, 44(2):128-135, 2004.

Hobbs, J.W., Greene, R.J., Patterson, E.A., 2003, A novel instrument for transient photoelasticity, Experimental Mechanics, 43(4):403-409, 2003.