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Richard Curran - One of the best experts on this subject based on the ideXlab platform.

  • Aircraft Component Multidisciplinary Design Optimization Considering Cost Performance
    14th AIAA Aviation Technology Integration and Operations Conference, 2014
    Co-Authors: Xiaojia Zhao, Richard Curran, Wim J. C. Verhagen
    Abstract:

    This paper presents a Multidisciplinary Design Optimization method to minimize the Direct Operating Cost and maximize the Surplus Value for aircraft components restricted by structural constraints. A parameterized DOC/SV analysis is proposed to link Cost performance and the structural design properties. This analysis is based on component design parameters including geometric sizes, material types and production process plans. The geometric parameters are used as the optimization variables for both the Cost/value and the structural performance evaluations. The adopted optimization algorithms include Genetic Algorithm, gradient based optimization, hybrid Genetic Algorithm and pattern search, as well as hybrid Genetic Algorithm and gradient based optimization. The pros and cons for each algorithm are inspected. A series of optimization studies are performed for Airframe Weight, Production Cost, Direct Operating Cost and Surplus Value separately. A further comparison incorporating the optimization objectives, optimal design solutions and computation times is conducted to evaluate the presented method.

  • aero structure Direct Operating Cost estimation and sensitivity analysis within a knowledge based engineering system
    20th ISPE International Conference on Concurrent Engineering: Proceedings, 2013
    Co-Authors: Xiaojia Zhao, Richard Curran
    Abstract:

    This paper presents a methodology to incorporate Direct Operating Cost (DOC), Surplus Value (SV) and Sensitivity Analysis (SA) into a Knowledge Based Engineering (KBE) system. Based on a parametrically modeled product geometry, the system automatically generates manufacturable geometry as well as the material and production data required by the Product Breakdown Structure (PBS) and the Bill Of Materials (BOM). By taking each item from the BOM, DOC is estimated using a production Cost module and simplified weight estimation module. The presented application is able to perform an SA with respect to the geometric factors The parameterization of the geometry definition and the subsequent integration of automated DOC estimation provide a practical example of an advanced concurrent engineering applications. It strengthens aero-structure conceptual design from the Cost perspective. Because this design and analysis system is highly integrated and automated, the benefits in terms of short design time and moderate effort are highlighted. The overall findings lead to further analysis on aero-structure performance from a life cycle and total value perspective.

  • ISPE CE - Aero-structure Direct Operating Cost estimation and sensitivity analysis within a knowledge based engineering system
    2013
    Co-Authors: Xiaojia Zhao, Richard Curran
    Abstract:

    This paper presents a methodology to incorporate Direct Operating Cost (DOC), Surplus Value (SV) and Sensitivity Analysis (SA) into a Knowledge Based Engineering (KBE) system. Based on a parametrically modeled product geometry, the system automatically generates manufacturable geometry as well as the material and production data required by the Product Breakdown Structure (PBS) and the Bill Of Materials (BOM). By taking each item from the BOM, DOC is estimated using a production Cost module and simplified weight estimation module. The presented application is able to perform an SA with respect to the geometric factors The parameterization of the geometry definition and the subsequent integration of automated DOC estimation provide a practical example of an advanced concurrent engineering applications. It strengthens aero-structure conceptual design from the Cost perspective. Because this design and analysis system is highly integrated and automated, the benefits in terms of short design time and moderate effort are highlighted. The overall findings lead to further analysis on aero-structure performance from a life cycle and total value perspective.

  • Uncertainty and Sensitivity Analysis in Aircraft Operating Costs in Structural Design Optimization
    Journal of Aircraft, 2009
    Co-Authors: Richard Curran, Sylvie Castagne, Alan Rothwell, Mark Price, Adrian Murphy, Srinivasan Raghunathan
    Abstract:

    The paper focuses on the development of an aircraft design optimization methodology that models uncertainty and sensitivity analysis in the tradeoff between manufacturing Cost, structural requirements, and aircraft Direct Operating Cost. Specifically, rather than only looking at manufacturing Cost, Direct Operating Cost is also considered in terms of the impact of weight on fuel burn, in addition to the acquisition Cost to be borne by the operator. Ultimately, there is a tradeoff between driving design according to minimal weight and driving it according to reduced manufacturing Cost. The analysis of Cost is facilitated with a genetic-causal Cost-modeling methodology, and the structural analysis is driven by numerical expressions of appropriate failure modes that use ESDU International reference data. However, a key contribution of the paper is to investigate the modeling of uncertainty and to perform a sensitivity analysis to investigate the robustness of the optimization methodology. Stochastic distributions are used to characterize manufacturing Cost distributions, and Monte Carlo analysis is performed in modeling the impact of uncertainty on the Cost modeling. The results are then used in a sensitivity analysis that incorporates the optimization methodology. In addition to investigating manufacturing Cost variance, the sensitivity of the optimization to fuel burn Cost and structural loading are also investigated. It is found that the consideration of manufacturing Cost does make an impact and results in a different optimal design configuration from that delivered by the minimal-weight method. However, it was shown that at lower applied loads there is a threshold fuel burn Cost at which the optimization process needs to reduce weight, and this threshold decreases with increasing load. The new optimal solution results in lower Direct Operating Cost with a predicted savings of 640/m 2 of fuselage skin over the life, relating to a rough order-of-magnitude Direct Operating Cost savings of $500,000 for the fuselage alone of a small regional jet. Moreover, it was found through the uncertainty analysis that the principle was not sensitive to Cost variance, although the margins do change.

  • RESEARCH INTO INTEGRATED AIRCRAFT TECHNOLOGIES
    AIAA's 3rd Annual Aviation Technology Integration and Operations (ATIO) Forum, 2003
    Co-Authors: Srinivasan Raghunathan, Richard Curran, A.k. Kundu, Mark Price, Emmanuel Benard
    Abstract:

    Major customer requirements and design drivers in aerospace are highlighted. Some of the current research activities at Queens University Belfast in meeting the customer requirements are presented. Key Cost drivers were identified and a Cost model was developed and validated. The Cost model was used to develop methodologies for evaluation of the Cost benefits of Design for Manufacturing and Assembly, including trade -off studies between Aerodynamics, Manufacturing and Assembly for allocation of optimum tolerance s for minimum Cost. The results were extrapolated to a whole aircraft to estimate savings in Direct Operating Cost. The study showed (for Airbus 320 class aircraft) that with an approach towards Design for Manufacturing and Assembly, and focusing on the allocation of optimum tolerances, one percent reduction in aircraft Cost and correspondingly half of one percent reduction in Direct Operating Cost could be achieved. The work led to the setting up of a Center of Excellence on Integrated Aircraft Technol ogies at Queens University Belfast, brief details of which are also given in the paper.

A. A. Smailys - One of the best experts on this subject based on the ideXlab platform.

  • The PT6 engine: 30 years of gas turbine technology evolution
    Journal of Engineering for Gas Turbines and Power, 1994
    Co-Authors: M. Badger, A. Julien, A. D. Leblanc, S. H. Moustapha, A. Prabhu, A. A. Smailys
    Abstract:

    The PT6 engine entered service in the mid-1960s. Since then, application of new technology has enabled low-Cost development of engines approaching 1500 kW, the introduction of electronic controls, improved power-to-weight ratio, higher cycle temperature, and reduced specific fuel consumption. At the same time, PT6 field experience in business, commuter, helicopter, and trainer applications has resulted in engines with low Direct Operating Cost and a reputation for rugged design and a high standard of engine reliability. This paper will highlight some interesting examples of this technical evolution, including the development of electronic controls and the application of the latest three-dimensional aerodynamic and stress analysis to both compressor and turbine components.

  • The PT6 Engine: 30 Years of Gas Turbine Technology Evolution
    Volume 1: Aircraft Engine; Marine; Turbomachinery; Microturbines and Small Turbomachinery, 1993
    Co-Authors: M. Badger, A. Julien, A. D. Leblanc, S. H. Moustapha, A. Prabhu, A. A. Smailys
    Abstract:

    The PT6 engine entered service in the mid-1960’s. Since then, application of new technology, has enabled low Cost development of engines approaching 1500 KW, the introduction of electronic controls, improved power-to-weight ratio, higher cycle temperature and reduced specific fuel consumption. At the same time, PT6 field experience in business, commuter, helicopter and trainer applications has resulted in engines with low Direct Operating Cost and a reputation for rugged design and a high standard of engine reliability. This paper will highlight some interesting examples of this technical evolution, including the development of electronic controls and the application of the latest 3D aerodynamic and stress analysis to both compressor and turbine components.Copyright © 1993 by ASME

Srinivasan Raghunathan - One of the best experts on this subject based on the ideXlab platform.

  • Uncertainty and Sensitivity Analysis in Aircraft Operating Costs in Structural Design Optimization
    Journal of Aircraft, 2009
    Co-Authors: Richard Curran, Sylvie Castagne, Alan Rothwell, Mark Price, Adrian Murphy, Srinivasan Raghunathan
    Abstract:

    The paper focuses on the development of an aircraft design optimization methodology that models uncertainty and sensitivity analysis in the tradeoff between manufacturing Cost, structural requirements, and aircraft Direct Operating Cost. Specifically, rather than only looking at manufacturing Cost, Direct Operating Cost is also considered in terms of the impact of weight on fuel burn, in addition to the acquisition Cost to be borne by the operator. Ultimately, there is a tradeoff between driving design according to minimal weight and driving it according to reduced manufacturing Cost. The analysis of Cost is facilitated with a genetic-causal Cost-modeling methodology, and the structural analysis is driven by numerical expressions of appropriate failure modes that use ESDU International reference data. However, a key contribution of the paper is to investigate the modeling of uncertainty and to perform a sensitivity analysis to investigate the robustness of the optimization methodology. Stochastic distributions are used to characterize manufacturing Cost distributions, and Monte Carlo analysis is performed in modeling the impact of uncertainty on the Cost modeling. The results are then used in a sensitivity analysis that incorporates the optimization methodology. In addition to investigating manufacturing Cost variance, the sensitivity of the optimization to fuel burn Cost and structural loading are also investigated. It is found that the consideration of manufacturing Cost does make an impact and results in a different optimal design configuration from that delivered by the minimal-weight method. However, it was shown that at lower applied loads there is a threshold fuel burn Cost at which the optimization process needs to reduce weight, and this threshold decreases with increasing load. The new optimal solution results in lower Direct Operating Cost with a predicted savings of 640/m 2 of fuselage skin over the life, relating to a rough order-of-magnitude Direct Operating Cost savings of $500,000 for the fuselage alone of a small regional jet. Moreover, it was found through the uncertainty analysis that the principle was not sensitive to Cost variance, although the margins do change.

  • RESEARCH INTO INTEGRATED AIRCRAFT TECHNOLOGIES
    AIAA's 3rd Annual Aviation Technology Integration and Operations (ATIO) Forum, 2003
    Co-Authors: Srinivasan Raghunathan, Richard Curran, A.k. Kundu, Mark Price, Emmanuel Benard
    Abstract:

    Major customer requirements and design drivers in aerospace are highlighted. Some of the current research activities at Queens University Belfast in meeting the customer requirements are presented. Key Cost drivers were identified and a Cost model was developed and validated. The Cost model was used to develop methodologies for evaluation of the Cost benefits of Design for Manufacturing and Assembly, including trade -off studies between Aerodynamics, Manufacturing and Assembly for allocation of optimum tolerance s for minimum Cost. The results were extrapolated to a whole aircraft to estimate savings in Direct Operating Cost. The study showed (for Airbus 320 class aircraft) that with an approach towards Design for Manufacturing and Assembly, and focusing on the allocation of optimum tolerances, one percent reduction in aircraft Cost and correspondingly half of one percent reduction in Direct Operating Cost could be achieved. The work led to the setting up of a Center of Excellence on Integrated Aircraft Technol ogies at Queens University Belfast, brief details of which are also given in the paper.

  • Influence of Manufacturing Tolerance on Aircraft Direct Operating Cost (DOC)
    Journal of Materials Processing Technology, 2003
    Co-Authors: Richard Curran, Srinivasan Raghunathan, A.k. Kundu, D. Eakin, R. Mcfadden
    Abstract:

    Abstract The influence of manufacturing tolerance on Direct Operating Cost (DOC) is extrapolated from an engine nacelle to be representative of an entire aircraft body. Initial manufacturing tolerance data was obtained from the shop floor at Bombardier Aerospace Shorts, Belfast while the corresponding Costs were calculated according to various recurring elements such as basic labour and overtime labour, rework, concessions, and redeployment; along with the non-recurrent Costs due to tooling and machinery, etc. The relation of tolerance to Cost was modelled statistically so that the Cost impact of tolerance change could be ascertained. It was shown that a relatively small relaxation in the assembly and fabrication tolerances of the wetted surfaces resulted in reduced Costs of production that lowered aircraft DOC, as the incurred drag penalty was predicted and taken into account during the optimisation process.

  • Parametric Optimization of Manufacturing Tolerances at the Aircraft Surface
    Journal of Aircraft, 2002
    Co-Authors: A.k. Kundu, Srinivasan Raghunathan, J. Watterson, R. Macfadden
    Abstract:

    Up until now, aircraft surface smoothness requirements have been aerodynamically driven with tighter manufacturing tolerance to minimize drag, that is, the tighter the tolerance, the higher is the assembly Cost in the process of manufacture. In the current status of commercial transport aircraft operation, it can be seen that the unit Cost contributes to the aircraft Direct Operating Cost considerably more than the contribution made by the Cost of block fuel consumed for the mission profile. The need for a customer-driven design strategy to reduce Direct Operating Cost by reducing aircraft Cost through manufacturing tolerance relaxation at the wetted surface without unduly penalizing parasite drag is investigated. To investigate this, a preliminary study has been conducted at 11 key manufacturing features on the surface assembly of an isolated nacelle. In spite of differences in parts design and manufacture, the investigated areas associated with the assembly of nacelles are typical of generic patterns in the assembly of other components of aircraft. The study is to be followed up by similar studies extended to lifting surfaces and fuselage

R. Mcfadden - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Manufacturing Tolerance on Aircraft Direct Operating Cost (DOC)
    Journal of Materials Processing Technology, 2003
    Co-Authors: Richard Curran, Srinivasan Raghunathan, A.k. Kundu, D. Eakin, R. Mcfadden
    Abstract:

    Abstract The influence of manufacturing tolerance on Direct Operating Cost (DOC) is extrapolated from an engine nacelle to be representative of an entire aircraft body. Initial manufacturing tolerance data was obtained from the shop floor at Bombardier Aerospace Shorts, Belfast while the corresponding Costs were calculated according to various recurring elements such as basic labour and overtime labour, rework, concessions, and redeployment; along with the non-recurrent Costs due to tooling and machinery, etc. The relation of tolerance to Cost was modelled statistically so that the Cost impact of tolerance change could be ascertained. It was shown that a relatively small relaxation in the assembly and fabrication tolerances of the wetted surfaces resulted in reduced Costs of production that lowered aircraft DOC, as the incurred drag penalty was predicted and taken into account during the optimisation process.

A.k. Kundu - One of the best experts on this subject based on the ideXlab platform.

  • RESEARCH INTO INTEGRATED AIRCRAFT TECHNOLOGIES
    AIAA's 3rd Annual Aviation Technology Integration and Operations (ATIO) Forum, 2003
    Co-Authors: Srinivasan Raghunathan, Richard Curran, A.k. Kundu, Mark Price, Emmanuel Benard
    Abstract:

    Major customer requirements and design drivers in aerospace are highlighted. Some of the current research activities at Queens University Belfast in meeting the customer requirements are presented. Key Cost drivers were identified and a Cost model was developed and validated. The Cost model was used to develop methodologies for evaluation of the Cost benefits of Design for Manufacturing and Assembly, including trade -off studies between Aerodynamics, Manufacturing and Assembly for allocation of optimum tolerance s for minimum Cost. The results were extrapolated to a whole aircraft to estimate savings in Direct Operating Cost. The study showed (for Airbus 320 class aircraft) that with an approach towards Design for Manufacturing and Assembly, and focusing on the allocation of optimum tolerances, one percent reduction in aircraft Cost and correspondingly half of one percent reduction in Direct Operating Cost could be achieved. The work led to the setting up of a Center of Excellence on Integrated Aircraft Technol ogies at Queens University Belfast, brief details of which are also given in the paper.

  • Influence of Manufacturing Tolerance on Aircraft Direct Operating Cost (DOC)
    Journal of Materials Processing Technology, 2003
    Co-Authors: Richard Curran, Srinivasan Raghunathan, A.k. Kundu, D. Eakin, R. Mcfadden
    Abstract:

    Abstract The influence of manufacturing tolerance on Direct Operating Cost (DOC) is extrapolated from an engine nacelle to be representative of an entire aircraft body. Initial manufacturing tolerance data was obtained from the shop floor at Bombardier Aerospace Shorts, Belfast while the corresponding Costs were calculated according to various recurring elements such as basic labour and overtime labour, rework, concessions, and redeployment; along with the non-recurrent Costs due to tooling and machinery, etc. The relation of tolerance to Cost was modelled statistically so that the Cost impact of tolerance change could be ascertained. It was shown that a relatively small relaxation in the assembly and fabrication tolerances of the wetted surfaces resulted in reduced Costs of production that lowered aircraft DOC, as the incurred drag penalty was predicted and taken into account during the optimisation process.

  • Parametric Optimization of Manufacturing Tolerances at the Aircraft Surface
    Journal of Aircraft, 2002
    Co-Authors: A.k. Kundu, Srinivasan Raghunathan, J. Watterson, R. Macfadden
    Abstract:

    Up until now, aircraft surface smoothness requirements have been aerodynamically driven with tighter manufacturing tolerance to minimize drag, that is, the tighter the tolerance, the higher is the assembly Cost in the process of manufacture. In the current status of commercial transport aircraft operation, it can be seen that the unit Cost contributes to the aircraft Direct Operating Cost considerably more than the contribution made by the Cost of block fuel consumed for the mission profile. The need for a customer-driven design strategy to reduce Direct Operating Cost by reducing aircraft Cost through manufacturing tolerance relaxation at the wetted surface without unduly penalizing parasite drag is investigated. To investigate this, a preliminary study has been conducted at 11 key manufacturing features on the surface assembly of an isolated nacelle. In spite of differences in parts design and manufacture, the investigated areas associated with the assembly of nacelles are typical of generic patterns in the assembly of other components of aircraft. The study is to be followed up by similar studies extended to lifting surfaces and fuselage