Browsing by Author "Lone, Mudassir"

Now showing 1 - 16 of 16
  • Thumbnail Image
    ItemOpen Access
    Adopting exergy analysis for use in aerospace
    (Elsevier, 2017-08-05) Hayes, David; Lone, Mudassir; Whidborne, James F.; Camberos, José; Coetzee, Etienne
    Thermodynamic analysis methods, based on an exergy metric, have been developed to improve system efficiency of traditional heat driven systems such as ground based power plants and aircraft propulsion systems. However, in more recent years interest in the topic has broadened to include applying these second law methods to the field of aerodynamics and complete aerospace vehicles. Work to date is based on highly simplified structures, but such a method could be shown to have benefit to the highly conservative and risk averse commercial aerospace sector. This review justifies how thermodynamic exergy analysis has the potential to facilitate a breakthrough in the optimization of aerospace vehicles based on a system of energy systems, through studying the exergy-based multidisciplinary design of future flight vehicles.
  • Thumbnail Image
    ItemOpen Access
    Aeroelastic scaling for flexible high aspect ratio wings
    (AIAA, 2019-12-31) Yusuf, Sezsy; Pontillo, Alessandro; Weber, Simone; Hayes, David; Lone, Mudassir
    This paper provides an overview of the work conducted as part of the Cranfield BEAmReduction and Dynamic Scaling (BeaRDS ) programme, which aims to develop a methodologyfor designing, manufacturing and testing of a dynamically scaled High Aspect Ratio (HAR)Wing inside Cranfield 8’x6’ wind tunnel. The aim of this paper is to develop a methodologythat adopts scaling laws to allow experimental testing of a conceptual flexible-wing planformas part of the design process. Based on the Buckinghamπtheorem, a set of scaling lawsare determined that enable the relationship between a full-scale and sub-scale model. Thedynamically sub-scaled model is manufactured as a combination of spar, skin, and addedmass representing the stiffness, aerodynamic profile, and aeroelastic behaviour respectively.The spar was manufactured as a cross-sectional shape using Aluminium material, while theskin was manufactured using PolyJet technology. Compromises due to the manufacturingprocess are outlined and lessons learned during the development of the sub-scaled model arehighlighted.
  • Thumbnail Image
    ItemOpen Access
    Analysis of wake surfing benefits using a fast unsteady vortex lattice method
    (AIAA, 2019-01-08) Fleischmann, Dominique; Lone, Mudassir
    The computer simulation framework Flexit is used to analyse the fuel economy benefit of aircraft wake surfing. Wake surfing involves multiple aircraft flying in close formation during cruise conditions to reduce overall induced drag and improve overall fuel efficiency. The aircraft fly in echelon such that the kinetic energy lost in vortices generated by the lead aircraft can be partially recovered by the following aircraft flying in regions of the wake where induced velocities have an upwardly directed vertical component. We build on recent theoretical and flight test work by developing a medium fidelity methodology using Flexit for predicting potential performance benefits of wake surfing. We present results from a specific systematic parametric study that corresponds to a series of recent flight tests with two C-17 transport aircraft to demonstrate the methodology and predict the fuel savings that can be obtained by different arrangements of aircraft in a wake surfing formation. The predictions are compared with the flight test data and the trends observed in our simulations agree with the trends of the full scale tests.
  • Thumbnail Image
    ItemOpen Access
    Application of fibre optic sensing systems to measure rotor blade structural dynamics
    (Elsevier, 2021-03-09) Weber, Simone; Kissinger, Thomas; Chehura, Edmond; Staines, Stephen; Barrington, James; Mullaney, Kevin; Fragonara, Luca Zanotti; Petrunin, Ivan; James, Stephen; Lone, Mudassir; Tatam, Ralph P.
    This paper compares two fibre optic sensing techniques for vibration characterisation: (a) optical fibre Bragg grating (FBG) strain gauges and (b) a novel direct fibre optic shape sensing (DFOSS) approach based on differential interferometric strain measurements between multiple fibres within the same fibre arrangement. Operational mode shapes and frequency measurements of an Airbus Helicopters H135 bearingless main rotor blade (5.1 m radius) were acquired during a series of ground vibration tests undertaken in a controlled laboratory environment. Data recorded by the fibre optic instrumentation systems were validated using commercially available accelerometers and compared against a baseline finite element model. Both fibre optic sensing systems proved capable of identifying the natural frequencies of the blade in the frequency range of interest (0–100 Hz). The data from the FBG sensors exhibited a dependency on their position relative to the neutral axes of the blade, which meant that full characterisation of the flapping and lagging modes required careful consideration of sensor location in the chordwise direction. The DFOSS system was able to identify all structural dynamics, despite being located on the neutral axis in the lagging direction, due to its sensitivity to angle changes, rather than strain, and its biaxial measurement capability. The DFOSS system also allowed the operational mode shapes of the blade to be determined directly, without the requirement for strain transfer from the blade to the sensor and without the requirement for a model of the underlying structure. The accuracy of obtained natural frequencies and operational mode shapes is assessed, demonstrating the potential of the use of both fibre optic sensing systems for determining blade structural dynamics.
  • Thumbnail Image
    ItemOpen Access
    Bladesense – a novel approach for measuring dynamic helicopter rotor blade deformation
    (European Rotorcraft Forum, 2018-12-31) Weber, Simone; Southgate, Dominic; Mullaney, Kevin; James, Stephen; Rutherford, Robert; Sharma, Anuj; Lone, Mudassir; Kissinger, Thomas; Chehura, Edmond; Staines, Stephen; Pekmezci, Huseyin; Fragonara, Luca Zanotti; Petrunin, Ivan; Williams, Dan; Moulitsas, Irene; Cooke, Alastair; Rosales, Waldo; Tatam, Ralph P.; Morrish, Peter; Fairhurst, Mark; Atack, Richard; Bailey, Gordon; Morley, Stuart
    Technologies that allow accurate measurement of rotorblade dynamics can impact almost all areas of the rotorcraft sector; ranging from maintenance all the way to blade design. The BladeSense project initiated in 2016 aims to take a step in developing and demonstrating such a capability using novel fibre optic sensors that allow direct shape measurement. In this article the authors summarise key project activities in modelling and simulation, instrumentation development and ground testing. The engineering approach and associated challenges and achievements in each of these disciplines are discussed albeit briefly. This ranges from the use of computational aerodynamics and structural modelling to predict blade dynamics to the development of direct fibre optic shape sensing that allows measurements above 1kHz over numerous positions on the blade. Moreover, the development of the prototype onboard system that overcomes the challenge of transferring data between the rotating main rotor to the fixed fuselage frames is also discussed.
  • Thumbnail Image
    ItemOpen Access
    Development of a multi-directional manoeuvre for unified handling qualities investigation
    (MDPI, 2019-06-10) Dussart, Gaétan; Lone, Mudassir; Bailey, Roger
    A slalom and alignment tracking manoeuvre was developed for multi-directional handling qualities analysis of large transport aircraft in simulation environments. The manoeuvre is defined and scaled as a function of aircraft characteristics, flight conditions using a simple set of mathematical models. Throughout the manoeuvre, the trajectory and overall performances are monitored at a set of gross position and alignment control checkpoints methodically distributed and sized to buoy the task and allow handling qualities analysis based on Cooper Harper Ratings and quantitative data analysis. Initial tests have shown that the manoeuvre sizing method led to feasible manoeuvres at multiple points of the flight envelope of a large civil transport aircraft. The manoeuvre capability to highlight desirable and undesirable handling qualities was also highlighted based on the initial findings for a couple of commercial large transport aircraft, a high aspect ratio wing and in-flight folding wingtip aircraft concepts. The relevance and applicability of the manoeuvre for multi-directional studies are discussed and compared against a more conventional offset landing manoeuvre. Finally, the potential use of the manoeuvre for different aircraft type and test flight is also suggested based on augmented reality technology.
  • Thumbnail Image
    ItemOpen Access
    Fibre-optic measurement of strain and shape on a helicopter rotor blade during a ground run: 2. Measurement of shape
    (IOP Publishing, 2022-06-08) Kissinger, Thomas; James, Stephen W.; Weber, Simone; Mullaney, Kevin; Chehura, Edmond; Pekmezci, Huseyin H.; Barrington, James; Staines, Stephen E.; Charrett, Thomas O. H.; Lawson, Nicholas J.; Lone, Mudassir; Atack, Richard; Tatam, Ralph P.
    Optical fibre strain and shape measurement sensors were deployed on a rotor blade during a full-speed helicopter ground run, with real-time data wirelessly streamed from rotor hub-mounted sensor interrogators. In part 2 of a 2-part paper series, two-dimensional direct fibre-optic shape sensing (DFOSS), using fibre segment interferometry-based interrogation is investigated. The concept of blade shape change visualisation over one rotation period using rotation displacement surfaces is introduced and the usefulness of DFOSS data to gain additional insights by determining operational modal frequencies independently for both horizontal and vertical vibration directions of the blade is demonstrated.
  • Thumbnail Image
    ItemOpen Access
    Identification of in-flight wingtip folding effects on the roll characteristics of a flexible aircraft
    (MDPI, 2019-05-30) Dussart, Gaétan; Yusuf, Sezsy; Lone, Mudassir
    Wingtip folding is a means by which an aircraft’s wingspan can be extended, allowing designers to take advantage of the associated reduction in induced drag. This type of device can provide other benefits if used in flight, such as flight control and load alleviation. In this paper, the authors present a method to develop reduced order flight dynamic models for in-flight wingtip folding, which are suitable for implementation in real-time pilot-in-the-loop simulations. Aspects such as the impact of wingtip size and folding angle on aircraft roll dynamics are investigated along with failure scenarios using a time domain aeroservoelastic framework and an established system identification method. The process discussed in this paper helps remove the need for direct connection of complex physics based models to engineering flight simulators and the need for tedious programming of large look-up-tables in simulators. Instead, it has been shown that a generic polynomial model for roll aeroderivatives can be used in small roll perturbation conditions to simulate the roll characteristics of an aerodynamic derivative based large transport aircraft equipped with varying fold hinge lines and tip deflections. Moreover, the effects of wing flexibility are also considered.
  • Thumbnail Image
    ItemOpen Access
    In-flight wingtip folding: inspiration from the XB-70 Valkyrie
    (Embry-Riddle Aeronautical University, 2019-05-16) Dussart, Gaétan; Lone, Mudassir; O'Rourke, Ciaran; Wilson, Thomas
    Wingip folding can be used to extend aircraft wingspan, allowing designers to take advantage of reduced induced drag whilst respecting ground operational limitations. Such devices can also be used in-flight for a variety of other benefits including load alleviation and flight control. The majority of in-flight folding research takes inspiration in past developments made on the XB-70 Valkyrie, which used the folding devices for stability and lift performance benefits. In this paper, the authors investigate the capabilities of the folding wingtip system and potential scaling to large civil aircraft. Manufacturing details are used to size the actuators whilst the aerodynamic loading acting on the wingtip hinges is found from flight test results. Dimensions and aerodynamic loading at cruise of a set of conventional civil aircraft wing are used to evaluate the scaling potential of the system for controlled in-flight folding. An estimate of the weight penalty due to the folding device is also given and compared to structural weight savings on the XB-70. The results presented herein help in the evaluation of conventional actuator limits for in-flight folding using arguably the most inspiring military example of wingtip folding so far.
  • Thumbnail Image
    ItemOpen Access
    Investigating pilots’ operational behaviours while interacting with different types of inceptors
    (Springer, 2022-06-16) Korek, Wojciech Tomasz; Li, Wen-Chin; Lu, Linghai; Lone, Mudassir
    There are different designs of inceptors applied in the modern flight deck. How do pilots define how to precisely control the aircraft as their intention? Ten pilots have been asked to take part in the flight simulation trials. They were given tasks to execute using sidestick, Xbox gamepad and touchscreen controller and provide feedback using the System Usability Scale. The aim was to investigate the feasibility of replacing conventional inceptors in aircraft. The results have shown that there is a potential in introducing alternate Human-Computer Interaction (HCI) methods in the flight deck, especially in terms of learnability, however there is still a lot of work before it happens. This paper summarises the ‘pilot study’ results and shows the potential for further research.
  • Thumbnail Image
    ItemOpen Access
    Multi-objective optimal longitudinal flight control system design for large flexible transport aircraft
    (IEEE, 2018-11-01) Song, Sipeng; Whidborne, James F.; Lone, Mudassir; Molina-Cristobal, Arturo
    This paper presents a multi-objective evolutionary algorithm design of a longitudinal optimal controller for a large flexible transport aircraft. The algorithm uses a mixed optimization approach based on a combination of Linear Quadratic Regulator (LQR) control and a Multi-Objective Genetic Algorithm (MOGA) to search over a set of possible weighting function structures and parameter values in order to satisfy a number of conflicting design criteria. The proposed approach offers a number of potential optimal solutions lying on or near the Pareto optimal front of competing objectives. The approach is explained in this paper and some results are presented.
  • Thumbnail Image
    ItemOpen Access
    On wings with non-elliptic lift distributions
    (ICAS, 2021-09-10) Bragado-Aldana, Estela; Lone, Mudassir; Riaz, Atif
    Non-elliptic lift distributions were originally conceived by Prandtl as a solution for wings having optimal aerodynamic and structural efficiency. Since 1933, many researchers have expanded on this theory to confirm that it explicitly facilitates the trade-off between induced drag and weight, and have unveiled other potential benefits such as proverse yaw. This theory is seen as a promising alternative to redefine the underlying principles of conceptual wing design in the search for a step increase in efficiency. Given the recent revival of this approach, in this paper the authors present a concise review of its theoretical basis, the developments carried out in this area and their relevance to the future of aviation.
  • Thumbnail Image
    ItemOpen Access
    Regressor time-shifting to identify longitudinal stability and control derivatives of the Jetstream 3102
    (Elsevier, 2017-06-20) Yusuf, Sezsy; Lone, Mudassir; Cooke, Alastair; Lawson, Nicholas J.
    The Jetstream 31 G-NFLA aircraft is used as a national flying laboratory test vehicle for flight dynamics research and teaching purposes. It has been the subject of much theoretical and experimental modelling and therefore, the need for generating validation data through flight testing is critical. In this paper, the aircraft's short period pitch oscillation mode characteristics are identified using data from sixteen flight tests. An identification procedure based on the least squares method and reduced order state-space model is used and the need for pre-processing regressors due to the effects of sensor location and instrumentation delays is highlighted. It has been shown that time-shifting the regressors based on relative locations of the angle of attack vanes and the inertial measurement unit results in significant reductions in uncertainty bounds of the estimated aeroderivatives and also a model that provides a closer match to flight test data. The estimated models are validated using separate flight test data and the variations in aeroderivatives over a range of airspeeds and centre of gravity positions are also presented.
  • Thumbnail Image
    ItemOpen Access
    Size estimation tools for conventional actuator system prototyping in aerospace
    (American Institute for Aeronautics and Astronautics, 2019-01-06) Dussart, Gaétan; Lone, Mudassir; O'Rourke, Ciaran
    Predicting the size of an actuator capable of reaching given performance requirements isa critical step for any systems design. Thus, to help in the prototyping and early developmentstages of such devices, simple mathematical models were developed, which can be used withlittle knowledge in actuation system design. Based on physical phenomenons at the heart ofthe actuation mechanism, these models can be used to estimate diameter and length, and there-fore volume and weight of conventional actuators as a function of performance requirements.Models include linear hydraulic pistons and electric motors, divided into radial and axial fluxmachines. Off-the-shelf actuators and more aerospace specific products were used to validateand assess the accuracy of the models over a wide range of force and torque requirements.Simple sizing examples for aerospace actuation systems are also given as use-cases of the different tools. A discussion on model applicability, for various aircraft scales and applicationsconcludes the paper.
  • Thumbnail Image
    ItemOpen Access
    Understanding human behaviour in flight operation using eye-tracking technology
    (Springer, 2020-07-10) Korek, Wojciech Tomasz; Mendez, Arthur P.; Asad, Hafiz Ul; Li, Wen-Chin; Lone, Mudassir
    A clear understanding of how the pilot processes the information in the cockpit while carrying out particular tasks is crucial for developing the Human-Machine Interface and inceptors that help reduce pilot workload. Eye-tracking data synchronised with aircraft dynamics data is used here to study the high-workload scenario of executing an offset landing in an engineering flight simulator. The study focused on identifying differences in behavioural patterns between line pilots and test pilots. Evidence for significant differences were found regarding the ability to multitask and monitor aircraft states. The research output will lead to reduction of the pilot’s workload and, in further study, proposition of a new display setups and inceptors.
  • Thumbnail Image
    ItemOpen Access
    Verification of a low fidelity fast simulation framework through RANS simulations
    (Springer, 2019-07-22) Carrizales, Martin A.; Dussart, Gaétan; Portapas, Vilius; Pontillo, Alessandro; Lone, Mudassir
    Verification and validation of simulation models are critical steps in engineering. This paper aims at verifying the suitability of reduced order aerodynamic models used in an aeroservoelastic framework designed to analyze the flight dynamics of flexible aircraft, known as the Cranfield Accelerated Aircraft Loads Model. This framework is designed for rapid assessment of aircraft configurations at the conceptual design stage. Therefore, it utilizes or relies on methods that are of relatively low fidelity for high computational speeds, such as modified strip theory coupled with Leishmann–Beddoes unsteady aerodynamic model. Hence, verification against higher order methods is required. Although low fidelity models are widely used for conceptual design and loads assessments, the open literature still lacks a comparison against higher fidelity models. This work focuses on steady-trimmed flight conditions and investigates the effect of aerodynamic wing deformation under such loads on aerodynamic performance. Key limitations of the reduced order models used, namely fuselage and interference effects, are discussed. The reasons for the overall agreement between the two approaches are also outlined.