Browsing by Author "Kissoon, Sajal"

Now showing 1 - 7 of 7
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    Assessment of performance boundaries and operability of low specific thrust GUHBPR engines for EIS2025
    (American Society of Mechanical Engineers, 2022-04-25) Mo, Da; Roumeliotis, Ioannis; Mourouzidis, Christos; Kissoon, Sajal; Liu, Yixiong
    This paper aims to develop a robust design process by approaching the performance boundaries and evaluating the operability of the pursued geared turbofan engine with low specific thrust for EIS 2025. A two-spool direct-drive turbofan (DDTF) engine of EIS 2000 was improved according to aircraft specifications and technology boundaries in 2025. A series of optimized engines with consecutive fan diameters were established to seek the ideal engine by balancing SFC, weight and mission fuel burn. The fan diameter was proved to be a decisive factor for lowering SFC and energy usage. The cycle design optimization process achieved a thermal efficiency of approximately 52%, and a propulsive efficiency of 79.5%, which is 8.19% increase in propulsive efficiency by enlarging fan diameter from 1.6m to 1.9m. Meanwhile, the 1.9m-fan diameter engine achieved a reduction in SFC and fuel burn of 7.47% and 6.58% respectively which offers an overall reduction of 30.82% in block fuel burnt and CO2 emission compared to the DDTF engine. A feasibility check verified the viability of the designed optimum engine in terms of fan tip speed, stage loading and AN2. Dynamic simulation offered a deep understanding of transient behaviour and fundamental mechanism of the geared turbofan engine. An important aspect of this paper is the use of advanced CMC materials, which led to an improvement of 4.92% in block fuel burn and 2.93% in engine weight.
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    Assessment of the BWB aircraft for military transport
    (Emerald, 2020-04-06) Kissoon, Sajal; Mastropierro, Francesco; Nalianda, Devaiah; Rolt, Andrew Martin; Sethi, Bobby
    Purpose The growth in air mobility, rising fuel prices and ambitious targets in emission reduction are some of the driving factors behind research towards more efficient aircraft. The purpose of this paper is to assess the application of a blended wing body (BWB) aircraft configuration with turbo-electric distributed propulsion in the military sector and to highlight the potential benefits that could be achieved for long-range and heavy payload applications. Design/methodology/approach Mission performance has been simulated using a point-mass approach and an engine performance code (TURBOMATCH) for the propulsion system. Payload-range charts were created to compare the performance of a BWB aircraft with various different fuels against the existing Boeing 777-200LR as a baseline. Findings When using kerosene, an increase in payload of 42 per cent was achieved but the use of liquefied natural gas enabled a 50 per cent payload increase over a design range of 7,500 NM. When liquid hydrogen (LH2) is used, the range may be limited to about 3,000 NM by the volume available for this low-density fuel, but the payload at this range could be increased by 137 per cent to 127,000 kg. Originality/value The results presented to estimate the extent to which the efficiency of military operations could be improved by making fewer trips to transport high-density and irregular cargo items and indicate how well the proposed alternatives would compare with present military aircraft. There are no existing NATO aircraft with such extended payload and range capacities. This paper, therefore, explores the potential of BWB aircraft with turbo-electric distributed propulsion as effective military transports.
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    Assessment of the performance boundaries of very low specific thrust direct-drive turbofan engines at aircraft level for EIS 2025
    (GPPS Chania20, 2020-09-07) Kissoon, Sajal; Zhang, Fan; Mourouzidis, Christos; Roumeliotis, Ioannis; Pachidis, Vassilios
    Within the past decade, concerns over the environmental impact of civil aviation have pushed the research community towards the development of more efficient propulsion technology, which delivers a lower carbon and NOx footprint. The current progress achieved in the various specialised disciplines creates the need to redefine the performance barrier achievable by 2025 state-of-the-art aero-engines. This paper summarises some of the latest advancements within the gas turbine research community on the performance modelling and analysis of very low dspecific thrust direct-drive turbofan engines for EIS 2025. Engine and aircraft performance models were used to predict the extent of fuel burn reduction at aircraft level that could be achieved by reducing the engine specific thrust level , increasing operating pressure and temperature levels and applying technology factors representing a step beyond current state-of-the-art. The models represented modern three-spool direct-drive turbofans powering a typical A350XWB-type aircraft. The outputs of the engine design of experiments (DoE) exercise resulted in three most promising candidates. Targeting EIS in 2025, the final optimum design showed 14.81% block fuel improvement for a representative long (7000nm) range mission, accompanied by 30.9% penalty on engine weight. These results propose that with current technology level, at the lower end of the specific thrust range, there is still available design space for the direct-drive turbofan architecture
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    A characteristic-based 1D axial compressor model for stall and surge simulations
    (American Society of Mechanical Engineers (ASME), 2023-09-09) Kissoon, Sajal; Righi, Mauro; Pawsey, Lucas; Pachidis, Vassilios; Tunstall, Richard; Roumeliotis, Ioannis
    A low-order unsteady one-dimensional axial compressor and combustor model has been developed at Cranfield University as part of a larger unsteady gas turbine engine model, with the ability to simulate compressor stall and surge. The flow is resolved using the 1D unsteady Euler equations and source terms are used to model bleed extraction (and addition), pressure losses, and heat and work exchange. Species tracking is used in the combustor part of the model, using a semi-coupled approach, to keep track of the combustion products and unburnt fuel in the main gas path. The equations are solved using a Roe Approximate Riemann Solver, modified to handle the high magnitude, transient source terms necessary for this simulation. The performance of the compressor during the transient surge event is described by a set of compressor characteristics, including reverse flow and rotating stall regions, obtained from a validated 3D throughflow code, ACRoSS. To replicate the exact response of multi-stage compressors, stage-by-stage characteristics are used during reverse flow. The low-order method presented is successfully verified against ACRoSS for a high-power surge event of a coupled IPC and HPC configuration. The rate at which the total pressure at the outlet of the HPC collapses was calculated to be within 1%. This approach presents a faster alternative to high-fidelity CFD and can be used to investigate the compressor stall behaviour within minutes during the early design phase.
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    Dynamic simulation and aircraft level assessment of CMC implementation on GTF engine
    (Springer, 2022-12-16) Mo, Da; Roumeliotis, Ioannis; Liu, Yixiong; Mourouzidis, Christos; Kissoon, Sajal
    This paper dynamically simulated the geared turbofan engine with CMC turbine components, including impacts of fuel schedule, shaft inertia, volume packing, BOV schedule. Deliberated comparisons were performed between CMC engine and Inconel engine on aircraft level performance and transient behaviour. Heat load examination is included in flight mission analysis, which lays the basis on the gearbox efficiency map related to torque and rotational speed. Results indicate that IPC surge margin of the CMC case slightly fall 0.15% but maintain steady. The mitigated T4 overshooting phenomenon has offered a 30 K drop and thus extended turbine life. More importantly, Fan shaft inertia dominantly affects engine operability, whereas the blow-off air fraction severely impacts the low power setting operation. Further investigation of heat load reveals that power loss at take-off segment accounts for 1.1% of IP shaft input power, which is 3.98% higher than Inconel case. The thermal management system needs to be redesigned to absorb extra heat. On assessment of aircraft level performance, CMC engine provides superior profits in maximizing airline revenue. The predicted annual fuel cost saving is about 0.08 million dollars coming from block fuel reduction. NOx, noise and CO2 demonstrate obvious decline, approaching 5.9%, 1.0% and 4.9%, respectively.
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    Engine strip and build lab: a practical approach to learning gas turbine engines
    (Cambridge University Press (CUP), 2025-01) Anselmi Palma, Eduardo; Kissoon, Sajal; Hann, Gary; Pilidis, Pericles; Pachidis, Vassilios
    The world is currently undergoing a technological transformation with numerous innovative concepts emerging. This shift is driven by remarkable advancements in artificial intelligence and the urgent need for decarbonisation. With this comes a growing demand for skilled engineers who can actively contribute at any stage within the life cycle of a product. This can be the generation of new concepts at low Technology Readiness Levels or contributing actively to their development and operational safety. This paper explores the integration of a 1-day practical activity to reinforce theoretical concepts learned within a classroom-based environment. Small groups of students were given the opportunity of engaging with a small helicopter engine (Rolls-Royce Gnome engine) through the disassembly and reassembly of the exhaust and power turbine section while following the manufacturer’s manual and ensuring industrial norms for safe practice. This hands-on activity included an introduction to tooling, a Gnome familiarisation activity, and an introduction to inspection techniques. Based on the feedback recorded, the students experienced a notable improvement in their basic understanding by effectively reinforcing knowledge acquired within the classroom through active engagement with an actual gas turbine engine.
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    Liquefied natural gas for civil aviation
    (MDPI, 2020-11-13) Rompokos, Pavlos; Kissoon, Sajal; Roumeliotis, Ioannis; Nalianda, Devaiah; Nikolaidis, Theoklis; Rolt, Andrew Martin
    The growth in air transport and the ambitious targets in emission reductions set by advisory agencies are some of the driving factors behind research towards new fuels for aviation. Liquefied Natural Gas (LNG) could be both environmentally and economically beneficial. However, its implementation in aviation has technical challenges that needs to be quantified. This paper assesses the application of LNG in civil aviation using an integrated simulation and design framework, including Cranfield University’s aircraft performance tool, Orion, and engine performance simulation tool Turbomatch, integrated with an LNG tank sizing module and an aircraft weight estimation module. Changes in tank design, natural gas composition, airframe changes, and propulsion system performance are assessed. The performance benefits are quantified against a Boeing 737–800 aircraft. Overall, LNG conversion leads to a slightly heavier aircraft in terms of the operating weight empty (OWE) and maximum take-off weight (MTOW). The converted aircraft has a slightly reduced range compared to the conventional aircraft when the maximum payload is considered. Compared to a conventional aircraft, the results indicate that although the energy consumption is increased in the case of LNG, the mission fuel mass is decreased and CO2 emissions are reduced by more than 15%. These benefits come with a significant reduction in fuel cost per passenger, highlighting the potential benefits of adopting LNG for aviation