Gas Turbines (GTs) will figure prominently in complimenting the intermittent power generated by renewables, while varied fuel sources by 2050 are likely to include biofuels (the former a mixture of methane, carbon mono- and di-oxide and nitrogen - essentially low calorific value fuel) and perhaps shale gas and hydrogen. In meeting CO2 emissions targets, there will be a premium on designs that (i) have the highest fuel conversion efficiency and (ii) integrate with carbon capture and storage. Such designs include either humid air turbines (HAT) or schemes with extensive exhaust, or flue, gas recirculation together with the use of oxygen-enriched air. There is extensive techno-economic evaluation of these designs with no preferred 'winner' and it is likely that each will find extensive application. Thus, there will be a need to design combustion chambers to burn low calorific gases, with "oxidant" streams including up to 30% (w/w) of steam, pure oxygen or oxygen heavily diluted with Carbon dioxide. Such changes present formidable difficulties to flame stability and extinction. The design of low NOx combustion chambers has shown the value of computational fluid dynamics (CFD) in developing commercially viable designs and this trend will strengthen. Finally, the value of suitable sensors during development has proved its worth. This research identifies the gaps in existing physical understanding, CFD and optical sensors, to be addressed by "fundamental research", that need to be filled so that step change GT technologies can be developed by industry. This proposal will develop tools and understanding as follows: (i) On-line, near real time optical sensor to measure the 'Wobbe' index of fuel entering the gas turbine, since fast knowledge of the calorific value of highly variable bio- fuels is important for control of future GTs. (ii) Flame stability and extinction is associated with the existence of a critical 'rate of stretch' and the largest laminar flame speed that the flame can experience due to the aerodynamic flow field of the combustors. Designers, using CFD for flow prediction in combustion chambers, need to know these critical values for the range of fuels and oxidants, which will be in use up to 2050. Thus, this proposal will obtain measurements of these values in premixed and non-premixed flames as a function of preheat and pressure and analyse the process of flame extinction in laboratory and pilot scale model combustors using, amongst other instruments, detection of CO and formaldehyde by planar laser induced fluorescence. (iii) Low NOx emissions require the fuel to be well premixed and it is useful for development engineers to have access to an instrument, which can measure local fuel/air ratio on test stands. Building on previous successful development of an instrument based on natural chemiluminescent emissions from a flame, there will be an evaluation of its calibration as a function of pressure and humidity, the latter in the context of a HAT gas turbine design. (iv) Thermoacoustic instability is a destructive high intensity 'limit cycle', which is either avoided operationally or designs are improved largely by cut and try methods. Until recently, the transition to this limit cycle and the limit cycle itself were characterised by frequency and phase spectral analysis. Our recent work has shown that non-linear time series analysis reveals that transition to high amplitude oscillations retains a structure as determined by chaos theory. We will use this form of analysis to identify the fluid mechanical structures responsible for this behaviour, with the aim of devising methods to at least warn gas turbine operators of impending thermoacoustic instability. (v) The best available LES CFD methods will be evaluated using the measurements in the counterflow and model combustor geometries. There will also be direct assessment, through the measurements, of the 'sub-grid' contribution of LES methodology to calculations

The emission of carbon dioxide into the atmosphere has caused huge concerns around the world, in particular because it is widely believed that the increase in its concentration in the atmosphere is a key driver of climate change. If the current trend in the release of carbon dioxide continues, global temperatures are predicted to increase by more than 4 degrees centigrade, which would be disastrous for the world. With the increase in world population, the energy demand is also increasing. Coal-fired and gas-fired power plants still play a central role in meeting this energy demand for the foreseeable future, even though the share of renewable energy is increasing. These power plants are the largest stationary sources of carbon dioxide. Carbon capture is a technique to capture the carbon dioxide that is emitted in the flue gas from these power plants. This proposal seeks to make a significant improvement in the methods used for carbon capture in order to reduce the total costs. Post-combustion CO2 capture by chemical absorption using solvents (for example, monoethanolamine - MEA) is one of the most mature technologies. The conventional technology uses large packed columns. The cost to build and run the capture plants for power plants is currently very high because: (1) the packed columns are very large in size; (2) the amount of steam consumed to regenerate solvents for recirculation is significant. If we can manage to reduce the size of packed columns and the steam consumption, then the cost of carbon capture will be reduced correspondingly. From our previous studies, we found that mass transfer in the conventional packed columns used for carbon capture is very poor. This proposed research is expected to make very significant improvements in mass transfer. The key idea is to rotate the packed column so that it spins at hundreds of times per minute - a so-called rotating packed bed (RPB). A better mass transfer will be generated inside the RPB due to higher contact area. With an intensified capture process, a higher concentration of solvent can be used (for example 70 wt% MEA) and the quantity of recirculating solvent between intensified absorber and stripper will be reduced to around 40%. Our initial analysis has been published in an international leading journal and it indicates that the packing volume in an RPB will be less than 10% of an equivalent conventional packed column. This proposal will investigate how to design and operate the RPB in order to separate carbon dioxide most efficiently from flue gas. The work will include design of new experimental rigs, experimental study, process modelling and simulation, system integration, scale-up of intensified absorber and stripper, process optimisation, comparison between intensified capture process and conventional capture process from technical, economical and environmental points of view. The research will include an investigation into the optimum flow directions for the solvent and flue gas stream (parallel flow or counter-current) for intensified absorber and the optimum design of packing inside the RPB. The proposal will also compare the whole system performance using process intensification vs using conventional packed column for a CCGT power plant. Based on this, an economic analysis will be carried out to quantify the savings provided by this new process intensification technology.

The UK needs carbon capture and storage (CCS) as part of its energy mix to minimise the cost of decarbonising our economy. CCS will have to fit into an electricity market that is increasingly dominated by inflexible nuclear and uncontrollable wind. It will therefore be vital that the CCS plants we develop are sufficiently flexible to interact with this new system, and balance the rapid start and cycling abilities with the lowest possible capital and operating costs. Flexible CCS will be characterised by the ability to simultaneously interact with the complex electricity system of the future and also the downstream CO2 transport and storage system. Rather than burning fuel purely in response to electricity price, CCS operators will also have to factor in waste storage costs, which will suffer similar complexity due to constraints on CO2 transport and injection rates and gas composition. This project will identify the flexibility bottlenecks in the CCS chain and also promising options for the development of resilient CCS systems. These models will internally calculate CCS plant load factors and electricity wholesale prices, thereby enabling a rigorous, technologically- and temporally-explicit, whole systems analysis. Feedback from CO2 storage operations will exert an as-yet unknown impact on the feasible operating space of the decarbonised power plant. We will explicitly quantify the interactions between the above- and below-ground links in the CCS chain. Sample CCS chains developed will be assessed in more detail concerning their broader role in the UK energy system. The implications of technological improvements in critical technologies such as advanced sorbents, improved air separation technologies and the availability of waste heat will also be considered. On a larger scale, the inter-operation of sample UK-specific CCS networks with intermittent renewable energy generation will be examined from an internally consistent whole-systems perspective. The internalisation of exogenous boundary conditions (e.g., the role of renewable energy and CCS plant load factors) and the development of multi-source-to-sink CCS system models will enable the most accurate assessment to date of how CCS will fit into the UK energy system and would interact with other energy vectors. The linking of CCS and renewable energy generation system models will allow us to examine the opportunities and impacts associated with the co-deployment of renewable energy and CCS in the UK. This will feed into a wider policy analysis that will examine the dynamics of changing system infrastructure at intermediate time periods between now and 2050. Dissemination of research output will be continuous over the duration of the project. We will engage with the academic community via publication in the international peer reviewed scientific literature and presenting at selected conferences. Owing to the topical nature of this research, public engagement is a priority for us. We plan on creating and managing a project webpage will provide real time insight into project progress and intermediate conclusions and results. All research papers and presentations will be available from this site. Similarly, we will conduct a continuous horizon scanning activity as part of this project. Our website will be continuously updated with a view to providing an understanding of where our research fits in the broader UK and international research arena. This work will be carried out via the development and integration of detailed mathematical models of each link in the CCS chain. We have engaged with a leading UK-based software development company with whom we will work to make these models available to the academic and broader stakeholder community. Further, a version of the modelling tools suitable for use by the general public will also be prepared. It is expected that this tool will be analogous in form and functionality to the DECC 2050 Calculator.

Two basic approaches have been adopted by industry to establish a reliable Non Destructive Evaluation (NDE) procedure that is fit for purpose. 1. In aerospace and offshore, where many similar defects are found repeatedly through many inspections, the Probability of Detection approach can be used. This approach is based on well-founded receiver operating characteristics theory. 2. Where only a few defects are expected and each may be unique, as in the nuclear industry, then Technical Justification is used. This is a judicious mixture of trials, modelling and physically-based reasoning. The technical justification neither quantifies the likelihood of errors nor gives any guidance on the effectiveness of the inspection should any of these errors occurs. Our proposal will provide a methodology for identifying errors and for quantifying their effect on inspection reliability. A combination of Fault and Event Trees will be used to identify and quantify errors in the entire process. This will enable studies of how best to improve the reliability of any NDT technique within any NDE approach and therefore complements both the Probability of Detection and Technical Justification approaches. The novel aspects of this proposal are: 1. The cause-consequence approach carried through an entire NDT/NDE situation; 2. Making the maximum use of available data, in part through the use of Bayesian networks to establish the causal correctness of the Fault and Event trees without needing to acquire new data through either experiment or modelling; 3. Ensuring that the results are not biased by unwarranted tails in probability distributions of influencing factors; and 4. Development of a framework for any inspection task which is generic but can readily be customised for each specific application.Data libraries will form an important part of the output. A key measure of success will be the degree to which industry can use the tool created to identify cost-effective ways of improving the reliability of their NDT/NDE.

The emission of carbon dioxide into the atmosphere has caused huge concerns around the world, in particular because it is widely believed that the increase in its concentration in the atmosphere is a key driver of climate change. If the current trend in the release of carbon dioxide continues, global temperatures are predicted to increase by more than 4 degrees centigrade, which would be disastrous for the world. With the increase in world population, the energy demand is also increasing. Coal-fired and gas-fired power plants still play a central role in meeting this energy demand for the foreseeable future, even though the share of renewable energy is increasing. These power plants are the largest stationary sources of carbon dioxide. Carbon capture is a technique to capture the carbon dioxide that is emitted in the flue gas from these power plants. This proposal seeks to make a significant improvement in the methods used for carbon capture in order to reduce the total costs. Post-combustion CO2 capture by chemical absorption using solvents (for example, monoethanolamine - MEA) is one of the most mature technologies. The conventional technology uses large packed columns. The cost to build and run the capture plants for power plants is currently very high because: (1) the packed columns are very large in size; (2) the amount of steam consumed to regenerate solvents for recirculation is significant. If we can manage to reduce the size of packed columns and the steam consumption, then the cost of carbon capture will be reduced correspondingly. From our previous studies, we found that mass transfer in the conventional packed columns used for carbon capture is very poor. This proposed research is expected to make very significant improvements in mass transfer. The key idea is to rotate the packed column so that it spins at hundreds of times per minute - a so-called rotating packed bed (RPB). A better mass transfer will be generated inside the RPB due to higher contact area. With an intensified capture process, a higher concentration of solvent can be used (for example 70 wt% MEA) and the quantity of recirculating solvent between intensified absorber and stripper will be reduced to around 40%. Our initial analysis has been published in an international leading journal and it indicates that the packing volume in an RPB will be less than 10% of an equivalent conventional packed column. This proposal will investigate how to design and operate the RPB in order to separate carbon dioxide most efficiently from flue gas. The work will include design of new experimental rigs, experimental study, process modelling and simulation, system integration, scale-up of intensified absorber and stripper, process optimisation, comparison between intensified capture process and conventional capture process from technical, economical and environmental points of view. The research will include an investigation into the optimum flow directions for the solvent and flue gas stream (parallel flow or counter-current) for intensified absorber and the optimum design of packing inside the RPB. The proposal will also compare the whole system performance using process intensification vs using conventional packed column for a CCGT power plant. Based on this, an economic analysis will be carried out to quantify the savings provided by this new process intensification technology.