Moore's Law states that the number of active components on an microchip doubles every 18 months. Variants of this Law can be applied to many measures of computer performance, such as memory and hard disk capacity, and to reductions in the cost of computations. Remarkably, Moore's Law has applied for over 50 years during which time computer speeds have increased by a factor of more than 1 billion! This remarkable rise of computational power has affected all of our lives in profound ways, through the widespread usage of computers, the internet and portable electronic devices, such as smartphones and tablets. Unfortunately, Moore's Law is not a fundamental law of nature, and sustaining this extraordinary rate of progress requires continuous hard work and investment in new technologies most of which relate to advances in our understanding and ability to control the properties of materials. Computer software plays an important role in enhancing computational performance and in many cases it has been found that for every factor of 10 increase in computational performance achieved by faster hardware, improved software has further increased computational performance by a factor of 100. Furthermore, improved software is also essential for extending the range of physical properties and processes which can be studied computationally. Our EPSRC Centre for Doctoral Training in Computational Methods for Materials Science aims to provide training in numerical methods and modern software development techniques so that the students in the CDT are capable of developing innovative new software which can be used, for instance, to help design new materials and understand the complex processes that occur in materials. The UK, and in particular Cambridge, has been a pioneer in both software and hardware since the earliest programmable computers, and through this strategic investment we aim to ensure that this lead is sustained well into the future.

A key and urgent challenge in mechanical engineering is to increase the efficiency of machine components and thereby reduce energy consumption. Nationally this is needed to meet CO2 emission limits, to help cope with rising fuel costs, and to reduce dependence on imported energy supplies. In global terms, the environmental impact of increased machine use in countries such as China and India as these become prosperous can only be mitigated by large increases in machine efficiency. One of the main ways to increase machine efficiency is to reduce friction between moving surfaces. A very important source of friction in machine components originates in elastohydrodynamic (EHD) lubricated contacts. These occur in components based on elements that both roll and slide together, including in all rolling bearings, gears and cam/follower systems. EHD friction is of growing importance since, in combination with churning losses, it controls the efficiency of mechanical transmissions. It thus contributes directly to vehicle efficiency but also to the efficiency of many other machines, such as wind turbines and industrial gearboxes. We need to understand EHD friction both to predict it (during machine design) and to reduce it significantly via lubricant and surface design. The conditions within an EHD lubricant contact are extraordinarily severe; the pressure is usually > 1 GPa; the shear rate is typically 106 to 108 s-1; film temperature can rise by > 100 degree Celcius within the contact. Under these conditions even the simplest liquids are piezoviscous and highly non-Newtonian, exhibiting both viscoelastic behavior and extensive shear thinning. The EHD friction is determined by this non-Newtonian response. Hence, to predict EHD friction and thus the efficiency of machine components, rheological equations are needed that describe the way that shear stress depends on strain rate for lubricant films in EHD contacts. Unfortunately there is currently a fundamental disagreement in the tribology community as to the form of these constitutive equations. The uncertainty arises because we are unable to probe in any detail the shear stress/strain rate behavior of thin lubricant films under the very severe conditions present in EHD contacts. This disagreement and confusion about the flow behavior of lubricants in EHD contacts is unfortunate and damaging since it has impeded the development and acceptance of computer-based models to predict EHD friction of engineering components, as well as diverting attention from the challenge of devising molecular structures that minimize this friction. It is thus clear that we need an experimental method of studying and quantifying the local flow behavior of thin lubricant films at the extreme conditions present in EHD contacts. The research team has very recently developed a laser-induced imaging approach to obtain the through-thickness velocity profiles of confined viscous fluids and has shown that the rheology of such fluids in EHD contact is non-Newtonian and highly complex. The proposed project builds on research experience in the previous work and the goal of the current proposal is to develop such a new methodology to examine the rheology of realistic, low viscosity lubricants in high stress, high shear rate EHD contacts. The newly developed method will then be applied to explore the impact of lubricant molecular structure, experimental conditions and surface conditions on EHD flow behaviour. Fluorescence spectroscopy will also be used to measure local viscosity, pressure and temperature in EHD contacts. These results will be combined to check the validity of existing EHD rheological models will be tested and new models developed if necessary.

In order to improve the management of railway networks and provide the timetables that passengers demand throughout the week, track components with greater durability that are easier to maintain are essential. With these in place less access will be needed to the track, keeping it free for trains. The aim of this project is, through the use of process modelling and full-scale testing and modelling, to enable the effective design of a laser clad layer of premium material for application to a range of track components to reduce wear and the likelihood of rolling contact fatigue occurring. These are the two most prolific damage mechanisms in railway track. A major goal of the project is to comprehensively study the behaviour of cladded components on a test track to validate the modelling and laboratory work. The technique, as well as improving component life and reducing maintenance needs, will reduce costs by allowing lower grade rail material to be used and also in-situ repairs could be facilitated eventually, negating the need for components to be removed from track when they reach the end of their life. The project, while focussed on railway track applications will also consider vehicle components in parallel activity and ensure that the knowledge and fundamental knowledge gained on the integrity of cladded components through multi-scale modelling of different geometries and cladding parameters is transferred to other sectors where cladding is used, such as energy, oil and gas and aerospace.

The research will investigate the nature of the loading patterns imparted onto tidal stream turbines when positioned and operated within an array and develop operational procedures to mitigate the impacts of these extreme loading patterns. Exposure to open sea wave climates with high wave-current interactions will influence the power generating, structural integrity, product durability and maintenance requirements of the technologies deployed. The research will undertake both experimental and numerical analyses in a manner that will make the results and findings transferable to real-life implementations. This will inform developers of the peak and fluctuating loads that devices are exposed to in a commercial array environment and will also identify and test mitigating actions to be implemented in order to ensure the robustness and sustainability of the array. The dynamic, cyclic loadings on a tidal stream turbine have been shown to depend on the current profile and wave characteristics which can increase the severity of these loads. This must be considered in the design of the turbine. A turbine in an array will be subjected to more complex flows due to its position in the array, which will result in more diverse loading patterns, which must be fully understood by the turbine designers and operators. The project will therefore evaluate and measure the loading and performance of different configurations of tidal stream turbine arrays using numerical modelling and model scaled experiments. The numerical modelling will use fluid and structural modelling. An existing and proven, instrumented, laboratory scale turbine design will used for the tests. Initial work on a three turbine array will be undertaken to create models of a full-scale turbine array to determine the power output, loading patterns and accurate life-fatigue analysis based on realistic site deployment conditions. This information will be formulated to provide a basis for the industry to evaluate anticipated performance, monitoring needs, operational best practice and maintenance regimes in order to deliver the lowest cost of energy from tidal arrays

We are facing unprecedented global challenges around climate change, clean energy, water and sustainability - and these have, at their core, materials solutions. Critical materials for future technologies are often highly complex on multiple length scales, and hence extremely difficult to characterise with a single technique. They commonly involve low atomic weight, mobile elements (e.g. hydrogen, lithium, carbon, sulfur) that are the most challenging to quantitatively characterise in their in-operando state, due to their high rates of diffusion, reactivity and often very low contrast by conventional imaging techniques. Examples of such materials systems include; materials for hydrogen production and storage, battery systems; catalysts to generate new fuels or facilitate decarbonation of industrial processes; interfaces between soft- and hard-matter relevant to hybrid electronics and 'soft' robotics; as well as liquids or liquid- solid interfaces that are critical across the whole engineering and physical sciences research space from geological carbon sequestration, to lubrication in engines, to chemistry and bioengineering. We will create a world-leading cryo-EPS facility to act as a collaborative hub for research that will underpin the UK ambition for a net zero carbon future and a more sustainable society. It will enable the quantitative atomic to micro-scale investigation of light elements that are critical to a host of new technologies associated with a transition to a sustainable, resilient and healthy future society, providing new scientific insights that will drive technological innovation. The equipment will enable the quantitative investigation of light elements across orders of magnitude in length scale - from the micron to the atomic scale, providing an unprecedented opportunity for a step change in our fundamental understanding of these materials structure and chemistry - and ultimately their behaviour This facility will be based around a cryo hub that will allow samples to be transferred under high vacuum and at cryo conditions between three instruments (i) an atom probe, uniquely positioned to quantitively measure chemical composition of light mobile elements; (ii) a transmission electron microscope with a vacuum-cryo holder and optimised to measure the structure of sensitive samples and also their local bonding environment; (iii) a plasma FIB to allow samples to be prepared for both the atom probe and TEM which have both low contamination and also little damage, and able to perform large-scale 3D imaging. The combination of these instruments will give the UK a powerful characterisation capability that is unique worldwide, putting UK scientists in a leading position to tackle important and urgent global challenges.