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Future flight deck design: developing an innovative touchscreen inceptor combined with the primary flight display
Get PDFThe touchscreen has the potential to optimize the space usage and efficiency of the flight deck. Currently, touchscreens can combine the input and output functions of different systems. However, it does not yet serve as an inceptor to replace the sidestick or control column for aircraft manoeuvres. This study aims to examine the potential of a touchscreen as a flight inceptor compared with a traditional sidestick and gamepad. This research recruited 72 participants who interacted with three inceptors for both an instrument landing with disturbance and without disturbance using the Future System Simulator. The findings demonstrated that pilot performance, system usability and pilots’ situation awareness of touchscreen inceptors were significantly inferior to those of traditional sidesticks and gamepads. Compared to the sidestick and gamepad, the touchscreen provided a poorer situation awareness with the highest supply and demand. In addition, the performance of all inceptors was significantly influenced by disturbance. There is still a long way to go for certification of a touchscreen as an inceptor on the future flight deck. This research showed that even though the touchscreen inceptor scored the lowest on both SUS and SART, the majority of pilots agreed that the touchscreen inceptor provided a better attentional supply in challenging disturbance circumstances, providing proof of concept for its possible inclusion in flight deck design. There is a potential that the emerging touchscreen as an inceptor may develop further along with human-system integration flight deck design.This research is co-financed by the European Union through the European Social Fund (grant number POWR.03.02.00–00-I029).International Journal of Industrial Ergonomic
‘Greening’ an oil exporting country: a hydrogen and helium closed-cycle gas turbines case study
Get PDFHolistic decarbonisation requires collaborative efforts and substantial investments across diverse economic sectors. This study introduces an innovative national approach, blending technological insights and philosophical considerations to shape decarbonization policies and practices. Libya is the case study. The proposed framework involves submersible power stations with continuous-duty helium closed-cycle gas turbines to supply electricity demand and hydrogen. Extensive national data is analysed, incorporating factors such as sectoral consumption, sea temperature, and port locations. An analytical model is developed, providing a valuable foundation for realistic decarbonization scenarios. The model aims to maintain the benefits of current energy consumption, assuming a 2% growth rate, while assessing changes in a fully green economy. The results offer qualitative and quantitative insights on hydrogen use and an expected rise in electricity demand. Two scenarios are examined: self-sufficiency and replacing oil exports with hydrogen exports. This study provides a quantitative perspective on decarbonization, focusing on a submersible helium closed cycle gas turbine concept resistant to natural disasters and proliferation. Findings underscore the substantial changes and investments needed for this transition, identifying primary needs of 27 GW or 129 GW for self-sufficiency and exports, respectively. This foundational analysis marks the start of research, investment, and political agendas toward decarbonization.Clean Energy and Sustainabilit
Trauma in the courtroom: the role of prior trauma exposure and mental health on stress and emotional responses in jurors
Get PDFObjectives
Prior research indicates that jury duty can be distressing for some jurors. This study examined: (1) the influence of prior trauma characteristics (type, exposure, time since trauma), medical fear and mental health difficulties on stress and emotional responses during a mock trial and 1 week later; and (2) associations between early stress reactions during a trial on subsequent stress and emotional reactivity after exposure to skeletal evidence and 1 week later.
Methods
Mock jurors (n = 180) completed baseline self‐report mental health measures, read a summary of a murder case and were then exposed to graphic skeletal evidence. Stress and/or emotional responses were collected at baseline, after reading the case summary, before and after viewing the skeletal evidence and 7 days post‐trial.
Results
Participants reported a wide range of prior traumatic experiences, with nearly half reporting pre‐existing mental health difficulties. Average traumatic stress symptoms tripled from baseline to follow‐up, with 44% of participants meeting PTSD‐type criteria 7 days later. Medical fear and mental health difficulties were positively associated with some stress and/or emotional responses throughout the trial, with mixed findings concerning trauma characteristics, stress and emotional reactivity. Initial stress and emotional responses to case evidence were linked to later stress and emotional reactions, after accounting for pre‐existing trauma and mental health characteristics.
Conclusions
Past trauma experiences, mental health difficulties and immediate stress responses during a trial can exacerbate emotional and stress reactions. Addressing the psychological impacts of pre‐existing trauma symptoms could improve juror well‐being during this important civic duty.British AcademyThis work was funded by a grant from the British Academy (SG2122\210569).British Journal of Clinical Psycholog
Thrust rebalance to extend engine time on-wing with consideration of engine degradation and creep life consumption
Get PDFOver the years, airlines have consistently attempted to lower their operational costs and improve aircraft availability by applying various technologies. Engine maintenance expenses are one of the most substantial costs for aircraft operations, accounting for around 30% of overall aircraft operational costs. So, maximizing aircraft time between overhaul is crucial to lowering the costs. The engine time on-wing is often limited due to the expiration of Life Limiting Parts, performance deterioration, etc.
This paper presents a novel method of rebalancing the thrust of engines of an aircraft to maximize the time between overhaul of the aircraft considering the performance degradation and creep life consumption of the engines. The method is applied to a model aircraft fitted with two model engines similar to GE90 115B to test the feasibility of the method with one engine degraded and the other engine undegraded. The obtained results demonstrate that for the aircraft flying between London and Toronto with 5,000 nominal flight cycles given to the engines, the time on-wing of the degraded engine could drop from 5,000 to 2,460 flight days due to its HP turbine degradation (1% efficiency degradation 3% flow capacity degradation), causing the same level of drop of time between overhaul of the aircraft. The time on-wing of the degraded engine could increase from 2,460 flight days without thrust rebalance to 3,410 flight days with thrust rebalance, i. e. around 38.6% potential improvement for the time between overhaul of the aircraft at the expenses of increased creep life consumption rate of the clean engine. The proposed method could be applied to other aircraft and engines.Journal of Engineering for Gas Turbines and Powe
Advancing fault diagnosis in aircraft landing gear: an innovative two-tier machine learning approach with intelligent sensor data management
Get PDFRevolutionizing aircraft safety, this study unveils a pioneering two-tier machine learning model specifically designed for advanced fault diagnosis in aircraft landing gear systems. Addressing the critical gap in traditional diagnostic methods, our approach deftly navigates the challenges of sensor data anomalies, ensuring robust and accurate real-time health assessments. This innovation not only promises to enhance the reliability and safety of aviation but also sets a new benchmark in the application of intelligent machine-learning solutions in high-stakes environments. Our method is adept at identifying and compensating for data anomalies caused by faulty or uncalibrated sensors, ensuring uninterrupted health assessment. The model employs a simulation-based dataset reflecting complex hydraulic failures to train robust machine learning classifiers for fault detection. The primary tier focuses on fault classification, whereas the secondary tier corrects sensor data irregularities, leveraging redundant sensor inputs to bolster diagnostic precision. Such integration markedly improves classification accuracy, with empirical evidence showing an increase from 95.88% to 98.76% post-imputation. Our findings also underscore the importance of specific sensors—particularly temperature and pump speed—in evaluating the health of landing gear, advocating for their prioritized usage in monitoring systems. This approach promises to revolutionize maintenance protocols, reduce operational costs, and significantly enhance the safety measures within the aviation industry, promoting a more resilient and data-informed safety infrastructure.AIAA SCITECH 2024 Foru
Aerodynamic instabilities in high-speed air intakes and their role in propulsion system integration
Get PDFHigh-speed air intakes often exhibit intricate flow patterns, with a specific type of flow instability known as ‘buzz’, characterized by unsteady shock oscillations at the inlet. This paper presents a comprehensive review of prior research, focused on unraveling the mechanisms that trigger buzz and its implications for engine stability and performance. The literature survey delves into studies concerning complex-shaped diffusers and isolators, offering a thorough examination of flow aerodynamics in unstable environments. Furthermore, this paper provides an overview of contemporary techniques for mitigating flow instability through both active and passive flow control methods. These techniques encompass boundary layer bleeding, the application of vortex generators, and strategies involving mass injection and energy deposition. The study concludes by discussing future prospects in the domain of engine-intake aerodynamic compatibility. This work serves as a valuable resource for researchers and engineers striving to address and understand the complexities of high-speed air induction systems.EU Erasmus+ ProgramAerospac
Dynamic path planning of UAV in three-dimensional complex environment based on interfered fluid dynamical system
Get PDFThe difficulties of path planning for unmanned aerial vehicles (UAVs) grow with the increase of static obstacles. Moreover, the presence of dynamic obstacles piles up the computation burden, as the UAVs need to dynamically replan and compute a new path to avoid them within an expanding search space. Existing studies on dynamic path planning have primarily evaluated algorithms in low-fidelity simulations and focused on improving computational efficiency. Nonetheless, these efforts remain insufficient for practical applications due to the limited computing powers of onboard processors, coupled with the significantly more cluttered nature of real-world environments. This paper introduces a dynamic autorouting program featuring the Interfered Fluid Dynamical System (IFDS) for adaptive path planning and a novel safeguarding function to ensure safety distances during obstacle avoidance. The proposed strategy brings a dynamic path planning framework, allowing UAVs to adaptively reroute to avoid areas and obstacles that will change throughout the flight in complex environments.AIAA SCITECH 2024 Foru
Real-time path planning considering static and dynamic obstacles
Get PDFThis paper introduces a real-time path planning strategy that effectively navigates around both static and dynamic obstacles. The approach combines the principles of Generalised Explicit Vector (GENEX) and Inverse Proportional Navigation (IPN), established algorithms in missile guidance known for their advantageous features such as low computation and closedform expressions. Leveraging these attributes, the proposed strategy addresses path planning challenges involving static and dynamic obstacles. The performance of the combined algorithm is assessed through a comprehensive simulation study in both 2D and 3D scenarios, considering multiple static and dynamic obstacles.AIAA SCITECH 2024 Foru
Dynamic swirl distortion characteristics in S-shaped diffusers using UCNS3D and time-resolved, stereo PIV methods
Get PDFEmbedded propulsion systems are key enablers of future aircraft configurations with expected benefits in reduced environmental impact and enhanced performance. Such propulsion systems are typically integrated with convoluted, complex air induction systems whose dynamic distortion characteristics previously found detrimental to the engine’s stability. Therefore, predictive capability for these complex flows is critical for the design of closely coupled engine – intake architectures. A new High-Order Delayed Detached Eddy Simulation (HODDES) is applied in this work to predict dynamic flow distortion within an S-shaped subsonic diffuser. The aim is to assess the ability of a new solver to predict unsteady and extreme distortion events. The HODDES results have been validated with Time-Resolved Stereo PIV (TR-PIV) data. The analysis shows that the HODDES captures the key mean and unsteady flow characteristics, the spectral content and unsteady distortion descriptor behavior across the Aerodynamic Interface Plane (AIP). Although the predicted mean velocity levels, flow field unsteadiness and range of predicted velocities are notably higher than the ones observed at the experiment by at least 40%, it is suggested that this is an artifact of a discrepancy between the axial planes where the CFD and test data were analyzed. The findings of the work suggest that the HODDES is broadly capturing the dynamic flow fields and with some further effort towards the calibration of its RANS models can be further used to study the integration of closely coupled fan system downstream of air induction systems.AIAA SCITECH 2024 Foru
Summary of the 6th Propulsion Aerodynamics Workshop: NASA 1507 Inlet
Get PDFThe 6th AIAA Propulsion Aerodynamics Workshop (PAW6) was held as part of AIAA’s Science and Technology Forum between January 21st -22nd 2023 in National Harbor, US. The goal of the workshop was to evaluate the current capability of computational fluid dynamics (CFD) on complex flows, pertinent to the high-speed propulsion community. PAW6 inlet test case was a mixed-compression supersonic inlet referred to here as the NASA 1507 inlet which featured a complex shock system attached at the entry along with a range of different flow control methods such as porous bleeds and vortex generators. Among several experimental test cases, four were selected for the workshop across a range of back-pressures, or inlet flow ratios, that yield different levels of pressure recovery, engine face distortion and bleed flows. Flow prediction data from 8 different participants was submitted using a total of 5 different computational domains for which 9 computational grids were developed and provided by Cadence. In general, flow predictions were better able to match the test data near the critical point of intake operation regardless of the flow solver, grid refinement level or turbulence model. Models with fully resolved rather than modelled bleed and/or vortex generators showed better results. Across the sub-critical range of operation, a notable under prediction of the flow ratio was seen across all flow solvers and models, indicating significant variations in the porous bleed modelling between the CFD datasets. The work indicates that more effort is needed by the relevant community toward the development of robust predictive capabilities, especially when complex flow control systems are in place for stability across the operating range.AIAA SciTech 2024 Foru