DSDS 22
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Item Open Access Development of a new Quantum Trajectory Molecular Dynamics Framework(Cranfield University, 2023-01-04T10:29:16Z) Svensson, PontusIn this work, we investigate matter under extreme conditions, the systematic study of which has only been possible due to the establishment of high-power laser facilities in the last decades. These states of matter are of interest for larger astronomical objects, but in particular for engineering systems for man-made nuclear fusion through high density, e.g. inertial confinement fusion, a concept for nuclear energy production based on commonly available elements. The property of matter under these conditions is largely unknown, hindering further technical development. Specifically, we examine plasma in the warm dense matter regime through numerical computation, a theoretically challenging regime as it is the transition from a cold dense system to a hot dense one. Therefore, neither the assumptions for cold nor hot systems are appropriate and everything should be accounted for. We utilise a quantum mechanical description -quantum mechanics being the microscopic theory of everything from molecules to metals - but for the high-temperature states under consideration characteristics of a plasma emerge. The particular problem we are addressing is related to the large electron-proton mass ratio, where even the lightest nucleus, the hydrogen ion, is almost 2000 times more massive than the electron resulting in very different velocities for ions and electrons. This is problematic, as to describe the ion motion, the computational costly description of electrons needs to be carried out for a long time. We address this with wave packet molecular dynamics describing the time evolution explicitly, impotent for the description of dynamical properties.Item Open Access Interior Illuminations(Cranfield University, 2023-01-04T12:28:01Z) Mcgregor, JamieThis image was gained from placing the head of a common LED torch into a 610 Xradia Versa System with an overall scan time of ~90 hours. By using a single high-resolution scan, a full 3D digital volume of the torch has been made which allows for us to view its inner components without damaging the object. Through analysing the data, it becomes clear which features represent the battery, circuitry, springs, buttons and aluminium within the torch. My PhD is centred around using X-Ray data to identify the defects and elements within metallic alloys for benefit to the quality control and manufacture processes. The use of these systems is both extremely time consuming and resourcefully expensive; being able to gain robust data from a single scan is invaluable for future research and efficiency.Item Open Access Organic Semiconductor Radiation Detectors for Alpha and Neutron Detection.(Cranfield University, 2023-01-04T10:30:48Z) Horner, AledIn recent decades organic electronics have entered mainstream use in consumer electronics found in households around the world. I will present radiation sensors based on organic semiconductor technology, and in particular applications related to detection of hadronic radiation. This includes α radiation. This technology also works with thermal and fast neutrons.Item Open Access Using Calibrated Samples for Uncertainty Analysis of X-Ray Computed Tomography(Cranfield University, 2023-01-04T12:28:26Z) Mcgregor, JamieX-Ray computed tomography is the process of using a series of projections of an object at different rotations to create a fully digital 3D representation of its internal and external features. These projections are gained through the use of a radiation emitting source and a specialised crystal detector on either side of the subject. Used in both the medical and industrial sectors, this process has been proven extensively valuable in discovering defects without any damage to the scanned sample.However, due to the non-uniform nature of the X-Rays and the variance of the equipment used to collect these projections, the spatial dimensions of the final data cannot be guaranteed to match the true sizes. When using this method to analyse features less than 30 μm, it becomes increasingly important to gain confidence that the results are correct. By using a tungsten carbide sphere and bespoke designed phantoms measured with a modern coordinate measuring machine, an uncertainty budget has been produced in reference to ISO guides of measurement and system optimisation. Through referencing this data to further gained results on new samples, the methodology has been proven to be successful.Item Open Access Obliterated Firearms Markings Documented in an African Country(Cranfield University, 2023-01-05T12:40:29Z) Henwood, BaileyFor the first time, a 'boots on the ground' approach has been taken to understand obliterations made to Small Arms and Light Weapons (SALW) recovered and documented in an African state, Country X. 126 firearms, primarily AK-pattern, were documented by Conflict Armament Research during a 10-year mission. These weapons were sanitised by local actors by removing identifying markings such as serial numbers and factory marks. Each obliteration was carefully analysed to determine the type of tool used by identifying the class characteristics of the toolmark, and to identify precisely which marks were removed. An obliteration code system has been developed, which identifies the tool type, completeness, marks removed, directionality, and any additional concealment. These codes have allowed to development of a database of obliterations and will, in turn, aid the intelligence-led investigation into the local forensic awareness, physical capabilities, and the motivation to obscure the SALWs identity. The results indicate that many of the weapons in each profile were likely sanitised by the same node-or were at least under the instruction of one common actor. This study also established that the forensic awareness within Country X is relatively low, as many of these marks may be recoverable using either traditional or novel means, if given the opportunity. The motivation for many of these weapons lies in the maintenance of monetary value, while concealing the identity to evade tracing efforts. This paper utilises a novel approach to understand weapon sanitisation in Country X, and how methods of obliteration can enhance further investigations in the region.Item Open Access Influence of carbon fibre orientation on the post-fire tensile behaviour of carbon fibre reinforced polymer (CFRP) laminates(Cranfield University, 2023-03-16T14:47:43Z) Aspinall, TimothyThe effect of carbon fibre orientation on the post-fire tensile behaviour of carbon fibre-reinforced polymer (CFRP) laminates is investigated in this study. CFRP specimens produced using unique carbon fibre orientations, unidirectional, bidirectional and multidirectional denoted S1, S2 and S3, respectively, are compared before and after exposure to thermal exposure. This study has practical usefulness as CFRP laminates containing these types of carbon fibre orientations are often utilised adjacent or close to fuel storage in aircraft that may present a fire hazard. The study's results showed that the S1 specimens exhibited the highest resistance to tensile failure before and after thermal exposure, whereas the S3 specimens exhibited the lowest resistance to tensile failure before and after thermal exposure. Furthermore, the data has shown that after thermal exposure, the tensile properties of the S1, S2 and S3 CFRP specimens reduced by 35%, 51% and 52%, respectively, compared to before thermal exposure. This loss in tensile properties can be attributed to the pyrolysis of the epoxy matrix and subsequent loss of interfacial bond strength, as the irradiance intensity used in the study was purposely chosen to represent the heat from a fire due to a small fuel leak in an aircraft resulting in temperatures lower than those required to oxidise the carbon fibres. Post-fire imagery has also shown that all the specimens in their undamaged state exhibit brittle failure; however, after thermal exposure, all CFRP specimens exhibit explosive delamination failure.Item Open Access Defence and Security Doctoral Symposium 2022 (DSDS22) Flyer(Cranfield University, 2022-08-30T11:41:27Z) Cranfield UniversityFlyer for the Defence and Security Doctoral Symposium (DSDS22) taking place 9-10 November 2022Item Open Access Not so crystal clear : Defects, hot spots and initiations in explosive crystals(Cranfield University, 2022-11-21T16:21:07Z) Mintoff, AliceNitroamine explosives are a crystalline material used in munitions, as a charge or propellant in powder form. These crystalline powders are compounded into formulations with other materials that can be tuned to fit requirements and their sensitiveness to insult is well understood. The larger part of these formulations are the crystalline explosives, which currently have less tunability. Researchers are aware that different crystal structures result in different materials properties. This is seen in nitramine explosives, such as RDX, where sensitivity can be reduced by manufacturing RDX particles to be more spherical and reducing the crystalline defects. They also know that hot spot formation, spots within the structure that heat up faster than surrounding areas, a contributing factor to initiation, is caused by defects within the crystal structures of the explosives. The types of defects, point, line, surface, substitutional, or interstitial, are not unique to energetic crystalline materials and a material could have any combination of these. A better understanding of how thse defects effect the formation of hot spots and the subsequent sensitivity will enable researchers to develop techniques that can produce highly tuned crystalline explosives. This thesis will focus on the nitroamine explosive, HMX, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine. Large single crystals will be grown using temperature lowering methods and the subsequent defects will then be identified and mapped out using Xray topography. Once characterised, the single crystals will then be subject to a shockwave which will cause initiation. Correlations between this initiation and the mapped defects will be identified.Item Open Access Obliteration Trends Around the World(Cranfield University, 2022-11-21T16:20:18Z) Henwood, BaileyIn both conflict zones and criminal investigations, the identification of firearms used in the commission of crimes is critical. This allows the tracking of weapons from manufacturers and legal owners to illicit actors and unauthorised users. The forensic investigation of firearms used in the commission of crime, in any theatre, is often complicated by the removal of identifying features like serial numbers, factory marks and manufacturer logos. This presentation will outline differences in obliteration techniques across the globe, while also highlighting potential motivations to conceal the firearms identity from the outset.Item Open Access Metals in extreme environments; Effect of multiple high velocity shots(Cranfield University, 2022-11-22T11:35:41Z) Stephenson, John-JosephDuring high strain rate scenarios such as an impact event, a compressive shock wave will propagate through the material. When this wave reaches a free surface, it will be reflected as a rarefaction wave. Interaction of these rarefaction waves can lead to localised tension developing in the material, leading to tensile failure, or spallation, which has been studied extensively over many years.What has been far less studied is the effect of a secondary compression on shock damaged material. This research will investigate this and determine if, and if so under what conditions, recompaction will occur in Aluminium and Titanium. This should provide fundamental knowledge of complex loading scenarios, aiding understanding of extreme events in both civil and military spheres. The work will involve the design of a passive' recovery system, which in addition to reducing the time required to produce samples for this work will have wider applications within the shock community.During high strain rate scenarios such as an impact event, a compressive shock wave will propagate through the material. When this wave reaches a free surface, it will be reflected as a rarefaction wave. Interaction of these rarefaction waves can lead to localised tension developing in the material, leading to tensile failure, or spallation, which has been studied extensively over many years. What has been far less studied is the effect of a secondary compression on shock damaged material. This research will investigate this and determine if, and if so under what conditions, recompaction will occur in Aluminium and Titanium. This should provide fundamental knowledge of complex loading scenarios, aiding understanding of extreme events in both civil and military spheres. The work will involve the design of a 'passive' recovery system, which in addition to reducing the time required to produce samples for this work will have wider applications within the shock community.Item Open Access Multistatic Synthetic Aperture Radar Phenomenology and Interferometry(Cranfield University, 2022-11-22T11:36:33Z) Hagelberg, AlexanderSynthetic Aperture Radar (SAR) is a remote sensing technique which provides high resolution imagery over large areas of the Earth. Unlike optical imagery, SAR operates in all-weathers, day or night. SAR images provide different information compared to electro-optical imagery and allows interferometry to be performed. Interferometry provides sensitive detection of ground height and of changes on the ground. This project investigates multistatic SAR geometries suitable to swarm radar platform concepts including SAR satellite constellations, as well as the processing of collected data.Item Open Access Visualising the Dispersion of Particles Within a Functionally Graded Material(Cranfield University, 2022-11-22T14:40:10Z) Powell, DanielFunctionally graded materials (FGMs) are designed to carefully alter material properties along a selected axis. This image shows FGMs created through mixing varying percentage volumes of high-density tungsten powder (in orange) with a low-viscosity epoxy (in white). Black regions show pores. As the epoxy cures the tungsten particles settle at various depths under gravity, notably in the 1%, 5% and 10% samples. Whilst there are multiple uses for FGMs, this research investigates if they could control the passage of damaging shock waves through a ceramic armour system, especially at the interlayer between a ceramic and metal.Item Open Access Until Sniffer Dogs Can Talk: CRIM-TRACK(Cranfield University, 2022-11-22T14:39:37Z) Hardy, IonaThis image is a digitally drawn short comic highlighting the CRIM-TRACK sniffer, a device that utilises a colourimetric sensor system to detect illicit compounds by their vapour at sensitivity rivalling a sniffer dog, but with better discrimination. Both detection methods can detect multiple substances, but sniffer dogs cannot signal which substance they have found, whilst the CRIM-TRACK sniffer can. The research aims to contribute to developing the CRIM-TRACK sniffer device, specifically the disposable colourimetric microchips used. This is being carried out by investigating the colour change mechanisms of select dyes when they encounter illicit compounds such as illicit drugs, homemade explosives, and their precursor chemicals using common analytical techniques. This data will allow future generations of the microchip to be tuned via dye selection for specific scenarios.Item Open Access Development of a soil analytical framework to facilitate early identification of the deleterious effects of emerging contaminants and chemicals of military concern on soil(Cranfield University, 2023-01-05T12:42:02Z) Persico, Federica; Coulon, Frederic; Ladyman, Melissa; Temple, TraceyInsensitive munitions are currently in use in military operations and training areas around the world and are usually filled with Insensitive High Explosive (IHE) formulations, such as combinations of constituents including 2,4-dinitroanisle (DNAN), 3-nitro-1,2,4-triazol-5-one (NTO) and RDX. Literature is available on the physiochemical nature of these materials, although the actual consequence of residues being deposited post-detonation in the environment is still an unexplored area of research. Of particular interest is the evaluation of soil health as it provides an early warning sign of contamination that may impact on human health and other environmental receptors. This research aimed to establish the concentrations of IHE in soil that would be detrimental to soil by quantifying residues from three detonated 155mm artillery shells filled with IHE composition (15% RDX, 32% DNAN and 53% NTO). The data collected was used to calculate the impact of 100 detonations to estimate the cumulative impacts. The estimated soil concentration values were simulated in outdoor soil mesocosms to establish high, medium, and low soil health boundaries for IHE in soil. The results obtained provide insight on the environmental impact of IHE filled munitions supporting future research in understanding consequences on soil health of detonated munitions.Item Open Access Nuclear Power: Finding the missing piece(Cranfield University, 2022-11-22T14:40:32Z) Mirza, MateenThere is now a clear consensus that our energy demands must be met through lower carbon solutions. As our global population continues to rise and aspires to higher living standards we are faced with increasingly ambitious energy targets in the transport, industry and power sectors. Nuclear power remains one of the few reliable energy sources. However, there remains a missing piece to the puzzle. Whether this relates to spent nuclear fuel reprocessing, the ongoing issue of waste disposal or improving our fleet of nuclear reactor systems is left to the viewer's thoughts.Item Open Access Towards a Method of Exploring the Limits of Low Frequency Time-Temperature Superposition Models in Predicting the High Frequency Response of Epoxy-Amine Resins(Cranfield University, 2022-11-24T17:31:34Z) Uncles, CarolineDMA has long been used to probe the viscoelastic properties of polymers. Not only has it been used to determine the glass transition temperature, but it is also often used to obtained data at higher frequencies through the principle of time-temperature superposition (TTS). There are several challenges which arise when using TTS and this poster highlights them in order to understand why TTS data is not so readily published within papers. The challenges include identifying your reference temperature, selecting your shift factor and the ideal master curve. These three challenges named are the main challenges with TTS and there is no one set method to overcome these when they are encountered.Item Open Access Development of Sustainable PPE for Higher Threat Clearance Operations by Humanitarian Organisations(Cranfield University, 2022-11-24T17:32:10Z) Brown, LauraHumanitarian demining is a hugely important task being undertaken all over the world with 59 countries and territories still contaminated by landmines and unexploded ordnance as of 2020. Personal Protective Equipment (PPE) for demining has traditionally been designed to protect against threats from legacy mines. However, over the last decade there has been an increase in the charge sizes used in these devices. It is currently unknown how the current PPE will perform and interact with these larger threats. Therefore, there is a need to understand whether improvements need to be made to both the standards used and the PPE itself. PPE that would be used by the police and militaries for these higher charge threats, e.g. IEDs and UXO, is highly developed, however it is extremely expensive and would be inappropriate for the demining industry. This project is therefore working to bridge the gap and help produce an effective and low-cost PPE solution that can be used by the humanitarian sector.Item Open Access Comparing the Decay of Physical and Digital Inoculation Against Disinformation(Cranfield University, 2022-11-24T17:32:28Z) Niklas HendersonSince entering the post-truth digital age, awareness in false information spreading online has increased rapidly. Despite this increased awareness it remains a serious problem, with Russian and Chinese state disinformation campaigns proving effective on online social networks (OSNs), impacting the wider UK political landscape. There are many areas of intervention across the mis- and disinformation landscape, including machine learning detection and classification methods, bad actor research, and some cognitive approaches. One cognitive-based approach is Inoculation Theory, originally developed by William J. McGuire. Inoculation theory follows the biological analogy, in that to increase resistance to persuasion the subject should be pre-exposed to a weakened version of a persuasive argument. Researchers have used inoculation theory in both physical and digital interventions, with participants yielding positive results identifying false information, and resisting 'fake news' This research focuses on understanding how the decay of inoculating effects differs relative to whether the inoculation intervention was delivered digitally or physically. Participants are inoculated to build resistance to disinformation using a board game, and results are compared to the inoculation decay of other, digital disinformation games.Item Open Access A Taxonomy for Contrasting Industrial Control Systems Asset Discovery Tools(Cranfield University, 2022-11-24T17:33:43Z) Samanis, ManolisThe number of tools for scanning industrial assets has grown considerably over the past decade. There is currently a plethora of free and commercial asset scanning tools which specialize in industrial control system (ICS) devices. However, to the best of our knowledge, there is no information pertaining to their actual capabilities and no experimental comparative comparison of their features. Moreover, it is not clear to what depth of scanning these tools can reach and whether the tools are suitable to use in a scaled industrial network architecture. This poster provides the first systematic features comparison available on free to use asset scanning tools, on the basis of an ICS scanning taxonomy we propose. Based on the taxonomy, we investigate tools scanning depth and validate results through experimentation on Siemens and Allen Bradley devices.Item Open Access Explosive Risk Assessment for Hydrogen Use in Domestic Applications(Cranfield University, 2022-11-24T17:32:51Z) Thawani, BonnyThe UK government aims to shift towards hydrogen-based energy for domestic applications between 2028-2035. While hydrogen is a carbon neutral resource, it has a very low ignition energy (0.019mJ) and high flammability range (4-75% in air). This project aims to understand the use of hydrogen in the natural gas network as a replacement for methane and especially assess the explosive threat posed by this. More specifically, the project focuses on the simulation (and experimental validation) of hydrogen gas flow in pipes and enclosed spaces (such as boiler cabinets) to enable visualisation of the explosive threat (including deflagration-to-detonation transition) in case of an accident. Mathematical and computational simulations were used to estimate the pressure loss of gases in pipes of different diameters (0.01m - 1m) and materials (Polyethylene and X52 steel). Simulations for the turbulent flow of hydrogen and methane in pipes of different diameters showed that hydrogen has to be transported at approximately 2.5-2.7 times the velocity used for methane, to replicate the pressure loss per meter. From the mathematical models, it was noted that different pipe materials influence the pressure loss in turbulent gas flow due to the relationship between absolute roughness of the material and friction factor. While the mathematical model and computational model have slightly different approaches to estimate turbulent flow, the results from the two are largely in agreement with an approximate error of 10%.