The INNFM Conference 2011

20th Anniversary Conference of the Institute of Non-Newtonian Fluid Mechanics

The British Society of Rheology has had a long association with Wales and Welsh rheologists and it is a real pleasure to report on this celebration of 20 years of the INNFM which unites the talents of rheologists in Aberystwyth, Cardiff and Swansea. The conference was held in Portmeirion, an Italianate village on the coast of North Wales (of which more below) and the INNFM booked all the accommodation in the village and more to host a gathering of 64 delegates and around 20 of their wives (or partners). This is not a massive gathering, but that really is the point. Over its 20 years the INNFM has organised many gatherings of this size which participants appreciate for the relaxed and friendly atmosphere that we find.

portmeirion group

The scientific programme has no parallel sessions and the organisers can be relied on to invite a series of top rheologists, old and young, who are, mostly, high quality speakers. Many of the speakers this year expressed their appreciation of the welcoming Institute; Gerry Fuller acknowledged its welcome to young rheologists and their wives while Gareth McKinley noted the significance of 1991 as the year of the founding of the INNFM, Gareth's PhD and his wedding. The sense of a rheological community was further demonstrated by expressions of concern at the absence and health of regular participants such as David James and Ralph Oliver. The BSR appreciates the close relationship between the Society and the INNFM and is grateful for the hospitality extended to it which allowed time in the programme for three BSR events, the AGM, the presentation of last year's Annual Award and the delivery of a Presidential Address by the retiring President. The meeting attracted a number of past Presidents of the BSR and senior office-holders in other rheological societies including the Society of Rheology, the European Society of Rheology and the International Committee on Rheology; at least twelve countries outside the UK were represented. Pictured above, outside the dining room, are the "Pacific Rim" contingent (from Western USA, Korea and Australia).

The programme ran from lunch on Monday 18th April to noon on Wednesday 20th April. It consisted of 29 papers presented in 7 lecture sessions, a poster session with 20 posters, two buffet lunches and two excellent dinners. Maybe the Institute should be renamed the Institute for Gourmet Rheology. Two dinners meant two after-dinner speeches - this is not for the faint-hearted and the dedicated rheologist may wish to skip to the section headed Rheology, below. Portmeirion villageOn the Monday, Peter Townsend gave us a history of the Institute which emphasised the relaxed nature of our hosts, pictured on beaches and holding aquatic meetings. It is worth setting alongside this lightheartedness the academic significance of the Institute, attested by the presence of Professor Marc Clement, Vice-Chancellor of the University of Wales, at the dinner. His presence did not appear to inhibit Peter and he went on to discuss the dangers inherent in a bilingual environment where an "out-of-office" e-mail can be mistaken for the requested translation. He alluded to the film-making side of the INNFM and the refusal of Ken Walters to allow a RHEOLLYWOOD sign on the hillside above his home. After the Tuesday Conference Dinner, Jeff Giacomin went in to bat for the guests (Jeff - I'll explain "cricket" and "metaphor" to you if you have a lot of spare time). He too had encountered some bilingual faux pas on his cycling around the area as well as a mystifying sign warning of a slow-moving vehicle one mile ahead (of the non-moving sign). He also recorded his gratitude in a peculiar way to those who had helped him out after his computer crashed on the flight over from Wisconsin. The Americans call this way of treating one's friends "roasting", so I guess I don't need to explain "metaphor" to Jeff.

The scientific sessions were held in the Hercules Hall under a mighty ceiling with representations of the 12 labours of Hercules. This was a fine setting, but one or two speakers failed to master the acoustics or construct their slides in a way that made them legible from the back of the hall.

There is room for a digression here on the topic of what speakers seriously expect their audience to learn from their presentations, but I shall not pursue this here - the majority of speakers gave me enough clarity to judge the conference to be a considerable scientific success, overall. The opening day gave us nine papers from eight countries: Spain (Cris Gallegos), Slovenia (Igor Emri), Switzerland (Adam Burbidge), USA (Gareth McKinley, Gerry Fuller), Canada (John Dealy), Australia (Paul Slatter), Sweden (Mats Stading) and Germany (Manfred Wagner) - enough to counter any idea that this might be a small provincial event. Seven of these nine papers could be classified as biorheology or rheometry (or both) and two other themes that could be identified at the conference were industrial rheology and computational rheology.

IMGP1362The centrepiece of the conference was a session reuniting two of the three speakers at the original (1991) INNFM conference, Marcel Crochet and Anthony Pearson. In place of the third, for this year's historic session we had David Boger and Roger Tanner. Each of these has been awarded the Gold Medal of the British Society of Rheology. Pictured are Roger, Marcel and Anthony. (David is pictured above, second from the left in the "Pacific Rim" picture. Marcel (now Baron Crochet) is a rheologist whose career took him to the heights of Rector of his university and he drew on his experience of rheology and academic politics to give us a talk on "Innovation" which held some warnings for academics in their ivory towers and for politicians about fostering innovation on a global scale without the constraints of sectional interests. The latter point is illustrated by the OECD which has a web site devoted to innovation strategy, but India, China, Brazil and Russia are not members. The warning to academics lies in the minimal cooperation with universities in the fostering of innovation in EU countries, notwithstanding the existence of the Framework Programmes (the current one is the 7th). Marcel alluded to the early days of BRITE-EURAM and collaboration between Aberystwyth and Louvain-la-Neuve and there is no doubt that collaborative academic research has been significant. Anthony referred to the lasting contribution of Jim Oldroyd (around 60 years ago), his first visit to Aberystwyth (40 years ago) and his review of rheology in science and engineering at the first INNFM meeting (20 years ago). His 2011 update highlighted the increased computational power available to us, the increasing role of physicists in rheology and the dominance of new materials. He identified materials science as the driving force for innovation. My notes have the phrase "acronym bombardment" but I not sure if this was Anthony's phrase or what I felt he was doing to me. He also alluded to the separation between rheology and earth sciences and identified a grand challenge in the prediction of lava flows and explosive volcanic eruptions, not to mention earthquakes. David's talk was based on his dealings with the mining industries and again we were taken on a journey from the scientific to the political. IMGP1379The problems that arise from mine waste are of a scale and importance second only to global warming and climate change. The record of tailings dam failures (such as that in Hungary in October 2010) is appalling. Rheology is important in discussion of dewatering and dealing with the thickened waste; yield stress is the important parameter, not concentration. There are regular meetings - "paste and thickened tailings seminars" - all over the world but they do not reach the people who can bring about change. David quoted Einstein on people "doing the same thing over again and expecting a different outcome" - that is Einstein's definition of insanity. The problems are financial - accounting practices don't favour taking a long-term view and regulators have neither the money nor the knowledge to be effective. There are rheological problems too - the talk ended with a challenge to study the interaction between shear and compression in suspensions. Roger balanced the session with a more concentrated dose of rheology; his historical reference was to the work of Rob Roscoe some 50 years ago, which Roger suggested has been undervalued; it provides a basis for the well-known Krieger-Dougherty formula. The motivation for discussing concentrated suspensions in a non-Newtonian matrix was the idea that this might be a way to model a semicrystalline material (such as polypropylene) or a material like bread dough with starch particles and a protein network. There is a shortage of experimental data at present but the hope is to use a simple approach in order to develop a model that can be used. There are a few conflicts between the messages from these four speakers, but these are issues to generate a creative tension rather than disagreements. I have in mind Roger Tanner's idea of a simple approach and Anthony Pearson's comments on the complexity of real industrial fluids. There is also Marcel Crochet's discussion of working within the structures that exist set against David Boger's searing criticism of the mining industry and its finance. I should end this section by recalling that David did highlight two or three signs of hope in industrial and investment practice. There is not space to do justice to any of the other presentations and I hope I may be allowed to select a few for comment on the basis of potential discussion or actual lively discussion at the conference, and express personal views which you may choose to attribute to my emeritus status and fading memory.

IMGP1366I would emphasize that there were a number of excellent papers that I am not even mentioning, including some on my own particular areas of interest. A pair of papers on computational rheology seemed almost too good to be true in the computational savings they offered. Roland Keunings gave us "Computational Rheology and the Proper Generalized Decomposition" followed by Paco Chinesta on "The Proper Generalized Decomposition for the Control of Polymer Processing Applications". For the non-mathematician there was the entertainmant value of demonstrating a smartphone application created to extract results for relevant parameters from a parametric solution obtained once for all. The idea behind PGD is similar to "Proper Orthogonal Decomposition" or "Principal Component Analysis" and it reduces the dimensionality of the (computational) problem by finding a small number of combinations of variables that give a good approximation to the system behaviour. At the end of the two papers, the question of how one apparently gets something for nothing was in my mind, but I do feel there is something well worth investigating in this work. Igor Emri's presentation had more of a philosophical flavour; the paper was entitled "Mechanics of Dissipative Systems: Some Open Questions". He started from Prigogine's idea that energy is required to maintain structure and wanted to regard energy as the primary quantity. He asserted that if one does not move the boundary (of a mechanical system) there is no force or stress. As with much philosophy, this left me with the question of whether something profound had been offered or whether there was anything there that was not obvious or even misconceived. Clearly in such a case, the fault may well be with the listener, but the discussion told me that I was not alone in having doubts.

Dan CurtisThe poster session was well supported and the winner of the BSR-TA poster award was Dan Curtis from Swansea University for his poster "Use of the spectral dimension in microstructural characterisation of fractal hydrogels and blood clots". The prize was announced by Gerry Fuller, on behalf of the panel of three judges, and awarded at the conference dinner by Peter Hodder, Senior Application Scientist of TA Instruments. By sheer coincidence there is a photographic record of Paula Moldenaers and Gareth Roberts studying the winning poster.IMGP1416 An o t h e r a w a r d made at the meeting was the 2010 Annual Award of the British Society of Rheology, made to João Maia who gave the Annual Award l e c t u r e o n "Another new rheometer" - a second version of his Controlled Stress Extensional Rheometer (CSER) which aims at ever higher strains so that the rupture of filaments can be studied. This lecture was followed by the Presidential Address by Oliver Harlen, the retiring President of the BSR, on "Numerical simulation of viscoelastic jet breakup in inkjet printing", nicely combining the computational and industrial themes.

Chris Petrie