Publications

Ryan presented the work from his MSc dissertation on solid-state battery at the Climate Exp0 conference in the Mitigation Solutions theme. With his supervisor Dr Christopher Vagg, he found that by utilising waste heat from the electrical power train, there is enough energy to heat thermally isolated solid-state battery modules in time for them to provide tractive power for a passenger vehicle. This is important as currently available solid-state batteries require an operational temperature of 60°C

For Alex's MRes summer project, he studied the effects of “Turbocompounding the Opposed-Piston 2-Stroke (OP2S) Engine” with a focus on quantifying the expected Brake Specific Fuel Consumption (BSFC) improvement. In order to achieve this, Alex needed to first create a model of an OP2S engine within GT Power, an engine simulation software package. After the MRes year was finished, Alex was able to turn the summer research project report into a conference paper which was published as part of the SAE WCX World Congress Experience Digital Summit in 2021.

Opposed-piston two-stroke engines reveal degrees of freedom that make them excellent candidates for next generation, highly efficient internal combustion engines for hybrid electric vehicles and power systems. The effect of crankshaft phasing and intake and exhaust port height-to-stroke ratios on a range of scavenging performance parameters and other effects are explored in depth in his latest article in Energies: “The Effect of Crankshaft Phasing and Port Timing Asymmetry on Opposed-Piston Engine Thermal Efficiency”, where it has been shown that lean operation favours port timing asymmetry, whereas, under stoichiometric conditions, best efficiencies are found during symmetrical port timing. 

Originating from his Master's thesis, Ryan and his supervisor Dr Chris Vagg have published their findings in a new journal article seeking to address the feasibility of a cold start procedure for solid state batteries in automotive applications. The proposed solution involves dividing the battery into sub-packs and heating them sequentially to the required 60°C, primarily using waste heat from the electric powertrain. This could allow high energy density solid state cells to be used despite their temperature constraints.

Howard's MRes Summer Project investigated the effect that AC internal heating had on the spatial temperature homogeneity of Lithium-ion cells. With his supervisor Dr Christopher Vagg, he found that the cylindrical MoliCel and DTP Pouch cells both demonstrated significant temperature gradients when heated from sub-zero temperatures. These gradients increased in magnitude with the size of the cell and for the pouch cells were affected further by the current gradients caused by tabs located at the same end of the battery.

In order to reduce the carbon footprint of the Internal Combustion Engine (ICE), biofuels have been in use for a number of years. One of the problems with first-generation (1G) biofuels however is their competition with food production. In search of second-generation (2G) biofuels, that are not in competition with food agriculture, a novel biorefinery process has been developed to produce biofuel from woody biomass sources. This novel technique, part of the Belgian federal government funded Ad-Libio project, uses a catalytic process that operates at low temperature and is able to convert 2G feedstock into a stable light naphtha. The bulk of the yield consists out of hydrocarbons containing five to six carbon atoms, along with a fraction of oxygenates and aromatics. The oxygen content and the aromaticity of the hydrocarbons can be varied, both of which have a significant influence on the fuel’s combustion and emission characteristics when used in Internal Combustion Engines. When used as a blend component, this novel 2G biofuel could help increase the sustainability of vehicle fuels. But, while exhaustive experimental and, although lesser in number, numerical investigations on combustion behavior have been performed for 1G biofuels, less information is available for 2G biofuels and especially this novel naphtha-like fuel. An extensive fuel compound property database and a fuel blend property calculator is readily available in literature, but their validity has not been tested for the novel 2G biofuel components. This article provides a first screening of the usability of these light naphtha components as blend components for gasoline and diesel drop-in fuels, by means of a freely available fuel component database and fuel blend calculator, concluding with an initial assessment of achievable blends and pointing out where further work is needed.

Originating from her PhD research on Mobility as a Service (MaaS), Rita wrote a short article for the City Changers website on balancing the benefits and challenges of implementing MaaS in an urban context, providing a few practical steps towards a MaaS implementation.

Thomas and Rob aided a Synchrotron X-Ray diffraction (SXRD) strain analysis experiment on Carbon Fibre Reinforced Polymers (CFRPs), at Diamond Lightsource. This was the first micro-scale quantification of micro-scale lattice strain in carbon fibre. This work determines the effect of load has on the axial and longitudinal strain of turbostratic atomic structure of the composite material.

With ever stricter legislative requirements for CO2 and other exhaust emissions, significant effort by Original Equipment Manufacturers (OEMs) have launched a number of different technological strategies to meet these challenges such as Battery Electric Vehicles (BEVs). However, a multiple technology approach is needed to deliver a broad portfolio of products since battery costs and supply constraints are considerable concerns hindering mass uptake of BEVs. Therefore, further investment in IC engine technologies to meet these targets are being considered, such as lean burn gasoline technologies and other high efficiency concepts such as dedicated hybrid engines. Hence, it becomes of sound reason to further embrace diversity and develop complementary technologies to assist in rapid conclusions in the transition to the next generation hybrid powertrains. One such approach is to provide increased valvetrain flexibility to afford new degrees of freedom in engine operating strategies. Freevalve is an electronically controlled, pneumatic spring-based, valve actuation system enabling independent control of ICE valves conceptualized by Koenigsegg’s Freevalve AB. Developed primarily in line with increasingly strict emissions legislations, preliminary findings have demonstrated that the cam-less engine technology withholds significant potential, offering up to 10% decreased fuel consumption and 60% less cold start emissions on an average drive cycle. This paper aims to demonstrate the most recent valve operating strategies enabled by the cam-less engine technology using a simplified 3-cylinder hybrid 1D engine model in GT-Suite.

Lois Player, AAPS CDT student, co-authors a study that finds that whilst climate anxiety is low amongst the UK public, it may be an important driver of climate action such as cutting down on waste.

The study published in the Journal of Environmental Psychology coincides with a new briefing paper from the Centre for Climate Change & Social Transformations focused on UK public preferences for low-carbon lifestyles. Its analysis suggests that lifestyle changes (for example, reducing car use or eating less meat), are increasingly seen as both feasible and desirable.

In the paper, the authors emphasise the importance of the media as a motivating force for the lifestyle changes required as we decarbonise. They suggest that the media and public discourse about climate anxiety has the power to create a positive vision for a greener, cleaner future which is significantly less dependent on fossil fuels.

Lois explained: “Our results suggest that the media could play an important role in creating positive pro-environmental behaviour change, but only if they carefully communicate the reality of climate change without inducing a sense of hopelessness.”