It could be argued that tradition and science are poles apart; while one is based on beliefs and long-established customs, the other is firmly grounded in rigorous research and methodology. Yet traditionally, they’ve both found their place in engineering. But as technology continues to advance where traditional methods falter, aren’t we better off just focusing on science?
The American Engineers' Council for Professional Development defines engineering as: “The creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them all as respects an intended function, economics of operation or safety to life and property.”
Yet, despite this clear steer towards scientific principles, tradition can still trump science in day-to-day execution. It is not difficult to find examples where long-established methods are still being used, whether they be barely, partially or fully based on hard scientific facts, simply because this is how things have been done for as long as anyone can remember. So long, in fact, that they’ve become part of a routine where the focus is often on applying established methodology rather than scrutinizing scientific foundations. But when science uncovers and develops new, more accurate and efficient engineering methodologies, wouldn’t it make sense to move away from tradition and fully embrace the new?
This is particularly relevant to ship design, where towing tank tests have been used for nearly 150 years to measure at model scale the performance of prospective ships. As a result, the focus of these tests has gradually shifted from improving overall methodology to simply mitigating flaws in the results.
And that’s not all. The familiarity of routine has bred a “better the devil you know” conservatism that the marine industry finds difficult to shed - something it will have to do in order to accept new, more accurate ways of designing ships.
But why are people so reluctant to accept the change? The strongest argument against a more widespread use of ship-scale CFD has always been the lack of validation data. This simply isn’t true; rather, the data exists - but strict confidentiality requirements mean that it cannot be shared at a wider industry level. The fact that many of those who own this data have done their own validation which they have used to move towards full-scale CFD simulations hasn’t done much to placate sceptics, in particular ship owners, who are used to traditional methods of design and don’t have the first-hand experience of CFD that many designers now do. And when the stakes are so high, who can blame them for lacking confidence without the relevant evidence?
In this situation, it is clear that the industry needs to break the deadlock and be more transparent in providing ship-scale data for public use and validation. In doing so, it would not only create opportunities to publicly demonstrate how CFD can predict full-scale performance within measurement error, it would also prove how advanced CFD practitioners really are in terms of maturity and experience in using technology to consistently and accurately predict ship performance.
The good news is that the opportunity for validation is closer than we think, and the wait for data is finally over. In November 2016, Lloyd’s Register will be hosting the first ever public workshop organized by the marine industry for ship-scale CFD validation. It is an invaluable opportunity for everyone involved in ship design to take part and help show the industry that the time has come to break with tradition and realize the true power of engineering.
All necessary data and case descriptions are now available for download from the Lloyd’s Register website.