My research interests span a few areas. These include thin film fluid mechanics, such as those encountered in coating and tribology, along with research interests in multi-disciplinary design optimisation and multiscale mechanics. These seemingly diverse fields of research are brought together by a fundamental analysis of how we represent complex problems for either optimisation or to span the scales of the problem.
Multiscale Lattice Optimisation
We have considerable interest in the design optimisation of lattices for both lightweight structural applications and structural morphing. The development of multiscale structural optimisation methodologies have been shown by the research group to have significant weight saving capability when compared to an equivalent single scale (SIMP based) topology optimisation results - of the order of 20% weight saving.
Multi-disciplinary Design Optimisation
I have a major interest in the complex and challenging problems presented in multidisciplinary design optimisation. The multi-fidelity response surface approaches I have used have enabled complex and frequently computationally expensive problems to be optimised with the minimum number of calls to the underlying computational models. We have done this for aeroelastic problems, as well as for the optimisation of compressor and turbine stages of gas turbines to maximise aero-thermodynamic performance while meeting the structural constraints demanded of the blades. It is from this that my additional interest of mesh parameterisation arises, preserving mesh connectivity and allowing each fluid simulation to be based on a previous iteration.
Tribology and Thin Film Fluid Dynamics
Much of my research to date has been on thin fluid film modelling, whether it is for applying thin layers of fluid onto a fast moving substrate for the purpose of changing its surface characteristics, or in modelling fluid film lubrication. Some of this work has been done using a multiscale approach where topographical features on the lubricated surface place new challenges on the usual lubrication approximation, requiring it to be solved using more complex fluid simulations. This method has been used in modelling the gravure coating process, as well as elastohydrodynamic lubrication with topographical features. As with my optimisation related research, response surface approaches have been used widely.
ResearchGate Profile: http://www.researchgate.net/profile/Rob_Hewson
et al., 2017, A predictive model for discrete cell gravure roll coating, Physics of Fluids, Vol:29, ISSN:1070-6631
et al., 2013, A semi-analytical model for the combined aeroelastic behaviour and gust response of a flexible aerofoil, Journal of Fluids and Structures, Vol:38, ISSN:0889-9746, Pages:3-21
Gao L, Hewson R, 2012, A Multiscale Framework for EHL and Micro-EHL, Tribology Transactions, Vol:55, ISSN:1040-2004, Pages:713-722
et al., 2012, Reviewing the technological challenges associated with the development of a laparoscopic palpation device, International Journal of Medical Robotics and Computer Assisted Surgery, Vol:8, ISSN:1478-5951, Pages:146-159
Hewson RW, Kapur N, Gaskell PH, 2011, A two-scale model for discrete cell gravure roll coating, Chemical Engineering Science, Vol:66, ISSN:0009-2509, Pages:3666-3674
et al., 2011, Multifidelity metamodel building as a route to aeroelastic optimization of flexible wings, Proceedings of the Institution of Mechanical Engineers Part C - Journal of Mechanical Engineering Science, Vol:225, ISSN:0954-4062, Pages:2115-2137
et al., 2011, A review of gravure coating systems, Convertech & E-print, Vol:1, ISSN:2185-6931, Pages:56-60
et al., 2015, A predictive model for discrete cell gravure roll coating, 11th European Coating Symposium 2015
et al., 2010, Aeroelastic analysis and gust response of a flexible airfoil, ISSN:0273-4508