OpenMDAO_conference.bib

@inproceesings{Babcock2023,
  author = {Babcock, Tucker and McKeever, Bryan and Hicken, Jason},
  title = {Multi-Disciplinary Design Optimization of an Electric Motor Considering Thermal Constraints},
  doi = {10.2514/6.2023-4342},
  booktitle = {AIAA Aviation Forum 2023},
  pdf = {http://openmdao.org/wp-content/uploads/2023/08/babcock2023_multidisciplinary_design_optimization.pdf},
  year={2023},
  notes = {AIAA 2023-4342}
}

@inproceedings{Pacini2021,
    author      = {Pacini, Bernardo and Yildirim, Anil and Davoudi, Behdad and Martins, Joaquim R. R. A. and Duraisamy, Karthikeyan},
    title       = {Towards Efficient Aerodynamic and Aeroacoustic Optimization for Urban Air Mobility Vehicle Design},
    booktitle   = {{AIAA} Aviation Forum 2021},
    url         = {https://www.researchgate.net/publication/353528455_Towards_Efficient_Aerodynamic_and_Aeroacoustic_Optimization_for_Urban_Air_Mobility_Vehicle_Design},
    pdf         = {https://www.researchgate.net/profile/Bernardo-Pacini/publication/353528455_Towards_Efficient_Aerodynamic_and_Aeroacoustic_Optimization_for_Urban_Air_Mobility_Vehicle_Design/links/61e1eff98d338833e36d275e/Towards-Efficient-Aerodynamic-and-Aeroacoustic-Optimization-for-Urban-Air-Mobility-Vehicle-Design.pdf},
    doi         = {10.2514/6.2021-3026},
    month       = {August},
    keywords    = {OpenMDAO},
    year        = {2021}
}

@inproceedings{Adler2022a,
  title     = {Aerostructural wing design optimization considering full mission analysis},
  author    = {Eytan J. Adler and Joaquim R. R. A. Martins},
  booktitle = {AIAA SciTech Forum},
  doi       = {10.2514/6.2022-0382},
  month     = {January},
  year      = {2022},
  keywords  = {OpenMDAO, OpenConcept, OpenAeroStruct, aerostructural, mission, optimization},
  pdf       = {http://websites.umich.edu/~mdolaboratory/pdf/Adler2022a.pdf}
}

@inproceedings{Yildirim2021a,
 author = {Anil Yildirim and Justin S. Gray and Charles A. Mader and Joaquim R. R. A. Martins},
 booktitle = {Proceedings of the AIAA SciTech Forum},
 doi = {10.2514/6.2021-0891},
 keywords = {ank, aeroprop},
 month = {January},
 title = {Performance Analysis of Optimized {STARC-ABL} Designs Across the Entire Mission Profile},
 year = {2021},
 pdf={https://www.researchgate.net/profile/Joaquim-Martins-4/publication/348243562_Performance_Analysis_of_Optimized_STARC-ABL_Designs_Across_the_Entire_Mission_Profile/links/6012cd4ea6fdcc071b9b4765/Performance-Analysis-of-Optimized-STARC-ABL-Designs-Across-the-Entire-Mission-Profile.pdf}
}

@inproceedings{Yildirim2021c,
 author = {Anil Yildirim and Justin S. Gray and Charles A. Mader and Joaquim R. R. A. Martins},
 booktitle = {AIAA Aviation Forum},
 doi = {10.2514/6.2021-3032},
 keywords = {ank, aeroprop},
 month = {August},
 title = {Coupled Aeropropulsive Design Optimization of a Podded Electric Propulsor},
 year = {2021},
 pdf={https://arc.aiaa.org/doi/epdf/10.2514/6.2021-3032}
}

@inproceedings{chin_battery_scaling_2021,
    Author = {Jeff Chin and Karsten Look and Ezra O. McNichols and Dustin Hall and Justin Gray and Sydney L. Schnulo},
    Booktitle = {AIAA Propulsion and Energy 2021 Forum},
    Title = {Battery Cell-to-Pack Scaling Trends for Electric Aircraft},
    Year = {2021},
    pdf = {http://openmdao.org/pubs/chin_battery_scaling_2021.pdf},
    doi = {10.2514/6.2021-3316},
    notes={AIAA 2021-3316}
}

@inproceedings{aretskin_hariton_2021a,
    Author = {Aretskin-Hariton, Eliot and Bell, Mark and Schnulo, Sydney  and Gray, Justin S.},
    Booktitle = {AIAA 2021 Aviation Forum},
    Title = {Power Cable Mass Estimation for Electric Aircraft Propulsion},
    Year = {2021},
    pdf = {http://openmdao.org/pubs/aretskin_power_cable_mass_estimation_aviation_2021.pdf},
    doi = {10.2514/6.2021-3021},
    notes={AIAA 2021-3021}
}

@inproceedings{hendricks2020,
  author = {Hendricks, Eric and Aretskin-Hariton, Eliot and Ingraham, Daniel and Gray, Justin and Schnulo, Sydney and Chin, Jeffrey and Falck, Robert and Hall, Dustin},
  booktitle = {AIAA 2020 Aviation Forum},
  doi = {10.2514/6.2020-3176},
  title={{Multidisciplinary Optimization of an Electric Quadrotor Urban Air Mobility Aircraft}},
  year = {2020},
  pdf = {https://ntrs.nasa.gov/api/citations/20205002459/downloads/Aviation2020_Final.pdf},
  notes={AIAA 2020-3176}
}

@incollection{Chin_2020,
    author = {Chin, Jeffrey C and Aretskin-Hariton, Eliot and Ingraham, Daniel and Hall, Dustin and Schnulo, Sydney L and Gray, Justin S. and Hendricks, Eric},
    booktitle = {AIAA Propulsion and Energy Forum},
    doi = {10.2514/6.2020-3567},
    title = {{Battery Evaluation Profiles for X-57 and Future Urban Electric Aircraft}},
    year = {2020},
    pdf = {http://openmdao.org/pubs/chin_battery_evaluation_2020.pdf}
}


@inproceedings{aretskin_hariton_scitech_2020,
    author = {Eliot Aretskin-Hariton and Sydney Schnulo and Eric Hendricks and Jeffryes Chapman},
    title = {Electrical Cable Design for Urban Air Mobility},
    booktitle = {AIAA Scitech 2020 Forum},
    year = {2020},
    address = {Orlando, FL},
    notes={AIAA 2020-0014},
    doi = {10.2514/6.2020-0014},
    pdf = {http://openmdao.org/pubs/Aretskin-Hariton_scitech_2020.pdf},
}

@inproceedings{falck_low_thrust_scitech_2020,
    Author = {Robert D. Falck and Steven L. McCarty and Jeffrey Pekosh and Kaushik Ponnapalli},
    Booktitle = {AIAA Scitech 2020 Forum},
    year = {2020},
    address = {Orlando, FL},
    notes= {AIAA 2020-2185},
    Doi = {10.2514/6.2020-2185},
    Title = {Implicit Formulations of Bounded-Impulse Trajectory Models for Preliminary Interplanetary Low-Thrust Analysis},
    pdf = {https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20200000233.pdf},
}

@inproceedings{Brelje2019d,
    Address = {Trondheim, NO},
    Author = {Benjamin J. Brelje and John P. Jasa and Joaquim R. R. A. Martins and Justin S. Gray},
    Booktitle = {NATO Research Symposium on Hybrid/Electric Aero-Propulsion Systems for Military Applications (AVT-RSY-323)},
    Institution = {NATO Research and Technology Organization},
    Doi = {10.14339/STO-MP-AVT-323},
    Keywords = {OpenMDAO, OpenConcept},
    Month = {October},
    Title = {Development of a Conceptual-Level Thermal Management System Design Capability in OpenConcept},
    Year = {2019},
    pdf = {http://openmdao.org/pubs/NATO_AVT-323-22_Brelje.pdf}
}

@inproceedings{hendricks_UAM_engine_opt_2019,
author = {Eric S. Hendricks and Eliot Aretskin-Hariton and Jeffryes W. Chapman and Justin S. Gray and Robert D. Falck},
title = "{Propulsion System Optimization for a Turboelectric Tiltwing Urban Air Mobility Aircraft}",
booktitle = {ISABE 2019},
publisher = {ISABE},
year = {2019},
address = {Canberra, Australia},
notes = {ISABE-2019-24365},
pdf={http://openmdao.org/pubs/ISABE_final.pdf}
}


@inproceedings{kambampati2019level,
  title="{Level Set Topology Optimization of Load Carrying Heat Dissipation Devices}",
  author={Kambampati, Sandilya and Gray, Justin S. and Kim, H. Alicia},
  booktitle="{AIAA Aviation 2019 Forum}",
  year={2019},
  doi={10.2514/6.2019-3558},
  notes={AIAA 2019-3558},
  pdf={http://openmdao.org/pubs/kambampati_level_set_thermal_2019.pdf}
}

@inproceedings{Thacker2019,
  address = {Dallas, TX},
  author = {Thacker, Robert and Blaesser, Nathaniel},
  booktitle = "{AIAA Aviation 2019 Forum}",
  month = {June},
  title = "{Modeling of a Modern Aircraft Through Calibration Techniques}",
  year = {2019},
  notes = {AIAA 2019-2984},
  doi = {10.2514/6.2019-2984},
  pdf = {https://arc.aiaa.org/doi/abs/10.2514/6.2019-2984}
}

@inproceedings{Jasa2019c,
    Address = {Dallas, TX},
    Author = {John P. Jasa and Shamsheer S. Chauhan and Justin S. Gray and Joaquim R. R. A. Martins},
    Booktitle = "{AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference}",
    Month = {June},
    Title = "{How Certain Physical Considerations Impact Aerostructural Wing Optimization}",
    Year = {2019},
    notes = {AIAA 2019-3242},
    Doi = {10.2514/6.2019-3242},
    pdf = {http://openmdao.org/pubs/jasa_aviation_2019.pdf}
}

@inproceedings{gray_bicoloring_2019,
  author = {Justin S. Gray and Tristan A. Hearn and Bret A. Naylor},
  title = "{Using Graph Coloring To Compute Total Derivatives More Efficiently in OpenMDAO}",
  booktitle = {AIAA Aviation 2019 Forum},
  publisher = {AIAA},
  year = {2019},
  address = {Dallas, TX},
  notes = {AIAA 2019-3108},
  doi = {10.2514/6.2019-3108},
  pdf = {http://openmdao.org/pubs/openmdao_bicoloring.pdf}
},

@inproceedings{hendricks_UAM_opt_2019,
  author = {Eric S. Hendricks and Robert D. Falck and Justin S. Gray and Eliot Aretskin-Hariton and Daniel Ingraham and Jeffryes W. Chapman and Sydney L. Schnulo and Jeff Chin and John P. Jasa and Jennifer D. Bergeson},
  title = "{Multidisciplinary Optimization of a Turboelectric Tiltwing Urban Air Mobility Aircraft}",
  booktitle = {AIAA Aviation 2019 Forum},
  publisher = {AIAA},
  year = {2019},
  address = {Dallas, TX},
  notes = {AIAA 2019-3551},
  doi = {10.2514/6.2019-3551},
  pdf={http://openmdao.org/pubs/hendricks_UAM_design_2019.pdf}
}

@conference {yildirim_bli_2019,
    title = "{Aeropropulsive Design Optimization of a Boundary Layer Ingestion System}",
    booktitle = {AIAA AVIATION Forum},
    year = {2019},
    publisher = {AIAA},
    organization = {AIAA},
    address = {Dallas, TX},
    keywords = {ANK, boundary layer ingestion, STARC--ABL},
    doi = {10.2514/6.2019-3455},
    author = {Anil Yildirim and Justin S. Gray and Charles A. Mader and Joaquim R. R. A. Martins},
    pdf={http://mdolab.engin.umich.edu/sites/default/files/Yildirim2019a-Aeropropulsive%20Design%20Optimization%20of%20a%20Boundary%20Layer%20Ingestion%20System.pdf}
}


@inproceedings {chin_battery_x57_2019,
    title = "{Battery Performance Modeling on SCEPTOR X-57 Subject to Thermal and Transient Considerations }",
    booktitle = "{AIAA Scitech 2019 Forum}",
    year = {2019},
    publisher = {AIAA},
    address = {San Diego, CA},
    author = {Jeff Chin and Sydney L. Schnulo and Thomas Miller and Kevin Prokopius and Justin S. Gray},
    notes={AIAA 2019-0784},
    doi={10.2514/6.2019-0784},
    pdf={http://openmdao.org/pubs/chin_battery_performance_x57_2019.pdf}
}

@inproceedings {ingraham_acoustic_opt_2019,
    title = "{Gradient-Based Propeller Optimization with Acoustic Constraints}",
    booktitle = "{AIAA Scitech 2019 Forum}",
    year = {2019},
    publisher = {AIAA},
    address = {San Diego, CA},
    author = {Daniel J. Ingraham and Justin S. Gray and Leonard V. Lopes},
    notes={AIAA 2019-1219},
    doi={10.2514/6.2019-1219},
    pdf={http://openmdao.org/pubs/ingraham_2019_scitech.pdf}
}

@inproceedings {chapman_turboshaft_opt_2019,
    title = "{Multi-point Design and Optimization of a Turboshaft Engine for Tiltwing Turboelectric VTOL Air Taxi}",
    booktitle = "{AIAA Scitech 2019 Forum}",
    year = {2019},
    publisher = {AIAA},
    address = {San Diego, CA},
    author = {Jeffryes W. Chapman},
    notes={AIAA 2019-1948},
    doi={10.2514/6.2019-1948},
    pdf={http://openmdao.org/pubs/chapman_turboshaft_opt_2019.pdf}
}

@inproceedings {falck_dymos_2019,
    title = "{Optimal Control within the Context of Multidisciplinary Design, Analysis, and Optimization}",
    booktitle = "{AIAA Scitech 2019 Forum}",
    year = {2019},
    publisher = {AIAA},
    address = {San Diego, CA},
    author = {Robert D. Falck and Justin S. Gray},
    notes={AIAA 2019-0976},
    doi={10.2514/6.2019-0976},
    pdf={http://openmdao.org/pubs/falck_dymos_2019_scitech.pdf}
}

@inproceedings {hendricks_load_flow_2019,
    title = "{Load Flow Analysis with Analytic Derivatives for Electric Aircraft Design Optimization}",
    booktitle = "{AIAA Scitech 2019 Forum}",
    year = {2019},
    publisher = {AIAA},
    address = {San Diego, CA},
    author = {Eric S. Hendricks and Jeffryes CHapman and Eliot Artskin-Hariton},
    notes={AIAA 2019-1220},
    doi={10.2514/6.2019-1220},
    pdf={http://openmdao.org/pubs/hendricks_load_flow_2019.pdf}
}

@inproceedings{Roy2019,
    Address = {San Diego, CA},
    Author = {Satadru Roy and Willam A. Crossley, and Bret K. Stanford and Kenneth T. Moore and Justin S. Gray},
    Title = "{A Mixed Integer Efficient Global Optimization Algorithm with Multiple Infill Strategy - Applied to a Wing Topology Optimization Problem}",
    Booktitle = "{AIAA SciTech Forum}",
    Keywords = {OpenMDAO},
    Month = {January},
    Year = {2019},
    pdf={http://openmdao.org/pubs/roy_scitech_2019_submitted.pdf}
}

@inproceedings{Jasa2019,
    Address = {San Diego, CA},
    Author = {John P. Jasa and Justin S. Gray and Jonathan A. Seidel and Charles A. Mader and Joaquim R. R. A. Martins},
    Title = "{2019 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference}",
    Booktitle = "{AIAA SciTech Forum}",
    Date-Added = {2018-12-03 12:23:56 -0500},
    Date-Modified = {2018-12-13 12:51:31 -0500},
    Doi = {10.2514/6.2019-0172},
    Keywords = {OpenMDAO},
    Month = {January},
    Title = "{Multipoint Variable Cycle Engine Design Using Gradient-based Optimization}",
    Year = {2019},
    pdf={http://openmdao.org/pubs/jasa_scitech_2019_submitted.pdf}
}


@phdthesis{GrayThesis2018,
  Author = {Justin S. Gray},
  School = {University of Michigan},
  Title = "{Design Optimization of a Boundary Layer Ingestion Propulsor Using a Coupled Aeropropulsive Model}",
  Year = {2018},
  pdf={http://openmdao.org/pubs/gray_phd_thesis_2018.pdf}
}

@inproceedings {gray_bli_2018,
    title = "{Aeropropulsive Design Optimization of a Turboelectric Boundary Layer Ingestion Propulsion}",
    booktitle = "{2018 Aviation Technology, Integration, and Operations Conference}",
    year = {2018},
    month = {6},
    publisher = {AIAA},
    address = {Atlanta, GA},
    author = {Justin S. Gray and Gaetan K. W. Kenway and Charles A. Mader and Joaquim R. R. A. Martins},
    notes={AIAA 2018-3976},
    doi={10.2514/6.2018-3976},
    pdf={http://openmdao.org/pubs/gray_bli_distortion_2018.pdf}
}

@inproceedings {falck_eats_2018,
    title = "{Multidisciplinary Optimization of Urban-Air-Mobility Class Aircraft Trajectories with Acoustic Constraints}",
    booktitle = "{AIAA/IEEE Electric Aircraft Technologies Symposium, AIAA Propulsion and Energy Forum}",
    year = {2018},
    publisher = {AIAA},
    author = {Robert D. Falck and Daniel Ingraham and Eliot Aretskin-Hariton},
    notes={AIAA 2018-4985},
    doi={10.2514/6.2018-4985},
    pdf={http://openmdao.org/pubs/falck_eats_2018.pdf}
}

@inproceedings {schnulo_x57_2018,
    title = "{Development of a Multi-Segment Mission Planning Tool for SCEPTOR X-57}",
    booktitle = "{2018 Multidisciplinary Analysis and Optimization Conference}",
    year = {2018},
    month = {6},
    publisher = {AIAA},
    address = {Atlanta, GA},
    author = {Sydney L. Schnulo and Jeff Chin, Robert D. Falck and Justin S. Gray and Kurt V. Papathakis and Sean C. Clarke and Nickelle Reid and Nicholas K. Borer},
    notes={AIAA 2018-3976},
    doi={10.2514/6.2018-3738},
    pdf={http://openmdao.org/pubs/x57_mpt_2018.pdf}
}


@inproceedings {Jasa2018a,
    title = "{Design and Trajectory Optimization of a Morphing Wing Aircraft}",
    booktitle = "{2018 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference}",
    year = {2018},
    month = {01},
    publisher = {AIAA},
    organization = {AIAA},
    address = {Kissimmee, FL},
    author = {John P. Jasa and John T. Hwang and Joaquim R. R. A. Martins},
    notes={AIAA 2018-1382},
    doi={10.2514/6.2018-1382},
    pdf={http://mdolab.engin.umich.edu/sites/default/files/Jasa_morphing_mission_SciTech_submitted.pdf}
}

@inproceedings {hwang_ode_mdo_2018,
    title = "{Solution of Ordinary Differential Equations in Gradient-Based Multidisciplinary Design Optimization}",
    booktitle = "{2018 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference}",
    year = {2018},
    month = {1},
    publisher = {AIAA},
    organization = {AIAA},
    address = {Kissimmee, FL},
    author = {John T. Hwang and Drayton W. Munster},
    notes={AIAA 2018-1646},
    doi={10.2514/6.2018-1646},
    pdf={http://openmdao.org/pubs/hwang_munster_ode_2018.pdf}
}

@inproceedings {hwang_ctol_mdo_2018,
    title = "{Large-Scale Multidisciplinary Optimization of an Electric Aircraft for On-Demand Mobility}",
    booktitle = "{2018 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference}",
    year = {2018},
    month = {1},
    publisher = {AIAA},
    organization = {AIAA},
    address = {Kissimmee, FL},
    author = {John T. Hwang and Andrew Ning},
    notes={AIAA 2018-1384},
    doi={10.2514/6.2018-1384},
    pdf={http://openmdao.org/pubs/hwang_electric_ctol_mdo.pdf}
}

@inproceedings {chung2018a,
    title = "{Implementation of Topology Optimization Using OpenMDAO}",
    booktitle = "{2018 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference}",
    year = {2018},
    month = {1},
    publisher = {AIAA},
    organization = {AIAA},
    address = {Kissimmee, FL},
    author = {Hayoung Chung and John T. Hwang and Justin S. Gray and Hyunsun A. Kim},
    notes={AIAA 2018-0653},
    doi={10.2514/6.2018-0653},
    pdf={http://openmdao.org/pubs/chung_topology_2018.pdf}
}

@inproceedings {roy_amiego_2018,
    title = "{Next Generation Aircraft Design Considering Airline Operations and Economics}",
    booktitle = "{2018 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference}",
    year = {2018},
    month = {1},
    publisher = {AIAA},
    organization = {AIAA},
    address = {Kissimmee, FL},
    author = {Satadru Roy and William A. Crossley and Kenneth T. Moore and Justin S. Gray and Joaquim R. R. A. Martins},
    notes={AIAA 2018-1647},
    doi={10.2514/6.2018-1647},
    pdf={http://openmdao.org/pubs/roy_amiego_2018.pdf}
}

@inproceedings{hwang2017reconfigurable,
  title={Reconfigurable model execution in the OpenMDAO framework},
  author={Hwang, John T},
  booktitle={18th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference},
  pages={3821},
  year={2017},
  pdf={http://openmdao.org/pubs/hwang_reconfigurability_2017.pdf}
}

@inproceedings{hendricks_pointer_pycycle_2017,
    Address = {Denver, CO},
    Author = {Hendricks, Erick S. and Falck, Robert D. and Gray, Justin S.},
    Booktitle = "{18th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference}",
    Month = {June},
    Title = "{Simultaneous Propulsion System and Trajectory Optimization}",
    Year = {2017},
    pdf = {http://openmdao.org/pubs/hendricks_pointer_pycycle_2017.pdf}
}

@inproceedings{falck_electric_thermal_2017,
    Address = {Denver, CO},
    Author = {Falck, Robert D. and Chin, Jeffrey C. and Schnulo, Sydney L. and Burt, Jonathan M. and Gray, Justin S.},
    Booktitle = "{18th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference}",
    Month = {June},
    Title = "{Trajectory Optimization of Electric Aircraft Subject to Subsystem Thermal Constraints}",
    Year = {2017},
    pdf = {http://openmdao.org/pubs/falck_traj_opt_electric_2017.pdf}
}


@inproceedings{gray_bli2017,
    Address = {Grapevine, TX},
    Author = {Justin S. Gray and Charles A. Mader and Gaetan K. W. Kenway and and Joaquim R. R. A. Martins},
    Booktitle = "{55th AIAA Aerospace Sciences Meeting (SciTech)}",
    Doi = {10.2514/6.2017-1753},
    Month = {January},
    Title = "{Approach to Modeling Boundary Layer Ingestion Using a Fully-Coupled Propulsion-RANS Model}",
    Year = {2017},
    pdf = {http://openmdao.org/pubs/gray_bli_2017.pdf}
}

@inproceedings{falck_2016,
 Title="{Parallel Aircraft Trajectory Optimization with Analytic Derivatives}",
 Author={Robert D. Falck and Justin S. Gray},
 Booktitle="{17th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, part of AIAA Aviation 2016 (Washington, DC)}",
 doi={10.2514/6.2016-3207},
 notes={AIAA-2016-3207},
 Year={2016},
 pdf = {http://openmdao.org/pubs/Falck_Gray-2016-Parallel_Aircraft_Trajectory_Optimization_with_Analytic_Derivatives.pdf}
}
@inproceedings{hearn_2016,
 Title="{Optimization of Turbine Engine Cycle Analysis with Analytic Derivatives}",
 Author={Tristan A. Hearn and Eric Hendricks and Jeffrey Chin and Justin S. Gray and Dr. Kenneth T. Moore},
 Booktitle="{17th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, part of AIAA Aviation 2016 (Washington, DC)}",
 doi={10.2514/6.2016-4297},
 notes={AIAA-2016-4297},
 Year={2016},
 pdf = {http://openmdao.org/pubs/Hearn_Hendricks_Chin_Gray_Moore-_2016_-Optimization_of_Turbine_Engine_Cycle_Analysis_with_Analytic_Derivatives.pdf}
}
@inproceedings{dener_kona_2016,
 Title="{Kona: A Parallel Optimization Library for Engineering-Design Problems}",
 Author={Alp Dener and Pengfei Meng and Jason Hicken and Graeme J. Kennedy and John Hwang and Justin S. Gray},
 Booktitle="{54th AIAA Aerospace Sciences Meeting}",
 Year={2016},
 pdf = {http://openmdao.org/pubs/Dener_Meng_Hicken_Kennedy_Hwang_Gray-_2016_-Kona_AIAA_SciTech_2016.pdf}
}

@inproceedings{graypycycle2016,
   Title = "{Thermodynamics of Gas Turbine Cycles With Analytic Derivatives in OpenMDAO}",
   Author = {Gray, Justin S. and Chin, Jeffrey and Hearn, Tristan and Hendricks, Eric and Lavelle, Thomas and Martins, Joaquim R. R. A.},
   Booktitle = "{54th AIAA Aerospace Sciences Meeting}",
   Year = {2016},
   Month = {January},
   pdf = {http://openmdao.org/pubs/Gray-_2016_-PyCycle_Thermodynamics.pdf}
}

@inproceedings{chinhyperloop2014,
   Title = "{Open-Source Conceptual Sizing Models for the Hyperloop Passenger Pod}",
   Author = {Jeffrey Chin and Justin S. Gray and Scott Jones and Jeff Berton},
   Booktitle = "{2015 AIAA SciTech Conference}",
   year = {2015},
   Month = {Janurary},
   Publisher = {American Institute of Aeronautics and Astronautics},
   pdf = {http://openmdao.org/pubs/Chin_Gray_Jones_Berton-_2015_-Hyperloop_Sizing_Thermal.pdf}
}

@inproceedings{heathgray2015nozzleopt,
   Author = {Christopher M. Heath and Michael A. Park and Eric J. Nielsen and Jan-Renee Carlson and Justin S. Gray},
   BookTitle = "{2015 AIAA SciTech Conference}",
   Month = {January},
   Year = {2015},
   Title = "{Aerodynamic Shape Optimization of a Dual-Stream Supersonic Plug Nozzle}",
   Publisher = {American Institute of Aeronautics and Astronautics},
   pdf = {http://openmdao.org/pubs/Heath_Gray-_2015_-Nozzle_Shape_Optimization.pdf}
}

@inproceedings{hendricks2014design,
   Title = "{Design Optimization of a Variable-Speed Power-Turbine}",
   Author = {Hendricks, Eric S. and Jones, Scott M. and Gray, Justin S.},
    Address = {Cleveland, Ohio},
    Booktitle = "{50TH AIAA/ASME/SAE/ASEE Joint Propulsion Conference}",
    Note = {AIAA-2014-3445},
    Month = {July},
    Organization = {AIAA},
    Year = {2014},
    pdf = {http://openmdao.org/pubs/Hendricks_Jones_Gray-_2014_-OTAC_Turbine_Opt.pdf}
}

@inproceedings{gray2014derivatives,
    Author = {Justin S. Gray and Tristan A. Hearn and Kenneth T. Moore and John Hwang and Joaquim Martins and Andrew Ning},
    Booktitle = "{15th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference}",
    Doi = {doi:10.2514/6.2014-2042},
    Month = {2014/07/08},
    Publisher = {American Institute of Aeronautics and Astronautics},
    Title = "{Automatic Evaluation of Multidisciplinary Derivatives Using a Graph-Based Problem Formulation in OpenMDAO}",
    Url = {http://dx.doi.org/10.2514/6.2014-2042},
    Year = {2014},
    pdf = {http://openmdao.org/pubs/Gray_Hearn_Moore_EtAl-_2014_-Multidisciplinary_Derivatives.pdf}
}

@inproceedings{Heath2012,
    Address = {Honolulu, Hawaii},
    Author = {Heath, Chritopher M. and Gray, Justin S.},
    Booktitle = "{8th AIAA Multidisciplinary Design Optimization Specialist Conference (MDO)}",
    pdf = {http://openmdao.org/pubs/Heath_Gray-_2012_-OpenMDAO_Frameork_for_Flexible_Multidisciplinary_Design_Analysis_and_Optimization_Methods.pdf},
    Pages = {1--13},
    Title = {{OpenMDAO: Framework for Flexible Multidisciplinary Design, Analysis and Optimization Methods}},
    Year = {2012}
}

@inproceedings{Gray2012,
    Address = {Honolulu, Hawaii},
    Author = {Gray, Justin S. and Moore, Kenneth T. and Hearn, Tristan A. and Naylor, Bret A},
    Booktitle = "{8th AIAA Multidisciplinary Design Optimization Specialist Conference (MDO)}",
    pdf = {http://openmdao.org/pubs/Gray_Moore_Hearn_Naylor-_2012_-A_Standard_Platform_for_Testing_and_Comparison_of_MDAO_Architectures.pdf},
    Pages = {1--26},
    Title = {{A Standard Platform for Testing and Comparison of MDAO Architectures}},
    Year = {2012}
}

@inproceedings{Coroneos2012a,
    Author = {R. M. Coroneos, and Pai, Shantaram},
    Booktitle = {NASA/TM 217433},
    Title = "{Deterministic Design Optimization of Structures in OpenMDAO Framework}",
    Month = {April},
    Year = {2012},
    pdf = {http://openmdao.org/pubs/Coroneos_Pai-_2012_-Deterministic_Design_Optimization_of_Structures_in_OpenMDAO_Framework.pdf}
}

@inproceedings{Coroneos2012b,
    Author = {Coroneos, Rula M.},
    Booktitle = {NASA/TM 217632},
    Title = "{Structural Analysis and Optimization of a Composite Fan Blade for Future Aircraft Engine}",
    Month = {August},
    Year = {2012},
    pdf = {http://openmdao.org/pubs/Coroneos-_2012_-Structural_Analysis_and_Optimization_of_a_Composite_Fan_Blade_for_Future_Aircraft_Engine.pdf}
}


@inproceedings{openmdao_derivatives,
        Address = {Indianapolis, Indiana},
        Author = {Moore, Kenneth T.},
        Booktitle = "{14th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference}",
        Month = {September},
        Organization = {AIAA},
        Title = "{Calculation of Sensitivity Derivatives in an MDAO Framework}",
        Year = {2012},
        pdf = {http://openmdao.org/pubs/Moore-_2012_-Calculation_of_Sensitivity_Derivatives_in_an_MDAO_Framework.pdf}
}

@inproceedings{gray_openmdao2010_b,
    Address = {Fort Worth, Texas},
    Annote = {2010-9101},
    Author = {Gray, Justin S. and Moore, Kenneth T. and Naylor, Bret A.},
    Booktitle = "{13th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, Fort Worth, TX, AIAA, AIAA-2010-9101}",
    Month = {August},
    Organization = {AIAA},
    Title = "{OpenMDAO: An Open-Source Framework for Multidisciplinary Analysis and Optimization}",
    url = {http://www.aric.or.kr/treatise/journal/content.asp?idx=134451},
    Year = {2010},
    pdf = {http://openmdao.org/pubs/Gray_Moore_Naylor-_2010_-OPENMDAO_An_Open_Source_Framework_for_Multidisciplinary_Analysis_and_Optimization.pdf}
}

@inproceedings{openmdao_1,
    Address = {Victoria, Canada},
    Author = {Moore, K.T. and Naylor, B.A. and Gray, J.S.},
    Booktitle = "{10th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference}",
    Month = {August},
    Note = {AIAA 2008-6069},
    Organization = {AIAA},
    Title = "{The Development of an Open-Source Framework for Multidisciplinary Analysis and Optimization}",
    Year = {2008},
    pdf = {http://openmdao.org/pubs/Moore_Naylor_Gray-_2008_-The_Development_of_an_Open_Source_Framework_for_Multidisciplinary_Analysis_and_Optimization.pdf}
}

@inproceedings{Gray2008,
    Address = {Hartford, CT},
    Author = {Gray, Justin S and Briggs, Jeffery L},
    Booktitle = "{44th AIAA/ASME/SAE/ASSE Joint Propulsion Conference and Exhibit}",
    Month = {July},
    Pages = {1--28},
    Title = {{Design of a Model Execution Framework : Repetitive Object-Oriented Simulation Environment}},
    Year = {2008},
    pdf = {http://openmdao.org/pubs/Gray_Briggs-_2008_-Design_of_a_Model_Execution_Framework_Repetitive_Object-Oriented_Simulation_Environment.pdf},
}

@inproceedings{AbdulKaiyoom2023a,
  abstract = {Optimal nacelle placement is critical to commercial or transport aircraft designs that use engines mounted with nacelles. Over-wing nacelle (OWN) configuration has a high potential to improve upon the conventional under-wing nacelle (UWN) configuration. OWN configurations have two critical benefits when compared to the conventional UWN configuration: 1. they ease the integration of high BPR and ultra-high BPR engines by alleviating ground clearance issues, and 2. they provide a significant amount of noise reduction because the wing blocks the noise of the fan and the jet. Despite their advantages, the OWN technology is not used in practical aircraft designs due to the difficulties in the aeropropulsive integration of the propulsion system. In this work, we propose using a coupled aeropropulsive design optimization framework to study the aeropropulsive integration for OWN configurations. The coupling behavior between the aerodynamics of the wing and the propulsion
system is extremely important. Especially in OWN configurations, the propulsion system is highly influenced by the aerodynamic performance of the wing. In this paper, we address the design problem of coupling between the aerodynamic and the propulsion system. We also explore wide range of design space to achieve the best practical design. The changes in wing shape are insignificant when the OWN configuration is optimized for different FPR. Wing in OWN performs better when the propulsor is close to the wing's root; however, the overall drag increases when the propulsor is close to the root. This increases the shaft power need. In addition, nacelle placement at the aft of the trailing edge shows better performance than forward of the trailing edge of the wing. These advancements in design optimization capabilities will be critical in the future design of OWN configurations to achieve more environmentally sustainable aircraft designs.},
  author = {M. A. Saja Abdul-Kaiyoom and Anil Yildirim and and Joaquim R. R. A. Martins},
  booktitle = {AIAA SciTech Forum},
  doi = {10.2514/6.2023-0327},
  keywords = {aeropropulsion, openmdao, xsede},
  month = {January},
  title = {Coupled Aeropropulsive Design Optimization of an Over-Wing Nacelle Configuration},
  year = {2023}
}

@inproceedings{Brelje2018a,
  address = {Cincinnati, OH},
  author = {Benjamin J. Brelje and Joaquim R. R. A. Martins},
  booktitle = {Proceedings of the AIAA/IEEE Electric Aircraft Technologies Symposium},
  doi = {10.2514/6.2018-4979},
  keywords = {OpenMDAO, ccavd},
  month = {July},
  title = {Development of a Conceptual Design Model for Aircraft Electric Propulsion with Efficient Gradients},
  year = {2018}
}

@inproceedings{Chauhan2018b,
  address = {Lisbon, Portugal},
  author = {Shamsheer S. Chauhan and Joaquim R. R. A. Martins},
  booktitle = {Proceedings of the 6th International Conference on Engineering Optimization, EngOpt 2018},
  doi = {10.1007/978-3-319-97773-7_38},
  keywords = {OpenMDAO, OpenAeroStruct},
  month = {September},
  pages = {418-431},
  publisher = {Springer},
  title = {Low-Fidelity Aerostructural Optimization of Aircraft Wings with a Simplified Wingbox Model Using {OpenAeroStruct}},
  year = {2018}
}

@inproceedings{Fouda2022,
  abstract = {Electric and hybrid-electric propulsion systems are key technologies for sustainable aviation. Electric propulsion systems introduce many design possibilities, which must be considered in the conceptual design stage to take full advantage of electrification. This makes for a challenging conceptual design problem. Architecture optimization can be applied to explore large design spaces and au tomatically find the best architectures for a set of requirements. Electric propulsion architecture optimization requires automated and flexible propulsion system modeling. It also requires the analysis of the propulsion architecture at an aircraft level to compute a meaningful objective function for the optimization. In this study, we present an approach for defining the propulsion system architectures and evaluating their aircraft-level performance. A propulsion architecture is defined using a modular interface, allowing architectures to be automatically evaluated on the
aircraft-level for a predefined mission. OpenConcept, an open source conceptual design and optimization toolkit, is used to implement the multidisciplinary problem. We present a case study of the electrification of a regional transport aircraft Beechcraft King Air C90GT with automated definition, integration and evaluation of five different propulsion systems. We perform multidisciplinary design optimization to minimize fuel burn and maximum takeoff weight for a sweep of design ranges and battery specific energies. Our approach opens the door to electric propulsion architecture optimization.},
  author = {Mahmoud Fouda and Eytan J. Adler and Jasper H. Bussemaker and Joaquim R. R. A. Martins and D. F. Kurtulus and Luca Boggero and Bj\"orn Nagel},
  booktitle = {33rd Congress of the International Council of the Aeronautical Sciences},
  keywords = {OpenMDAO. OpenConcept},
  month = {September},
  title = {Automated Hybrid Propulsion Model Construction for Conceptual Aircraft Design and Optimization},
  year = {2022},
  pdf = {https://www.icas.org/ICAS_ARCHIVE/ICAS2022/data/papers/ICAS2022_0593_paper.pdf},
}

@inproceedings{Jasa2018c,
  address = {Atlanta, GA},
  author = {John P. Jasa and Charles A. Mader and Joaquim R. R. A. Martins},
  booktitle = {AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference},
  doi = {10.2514/6.2018-3884},
  keywords = {CCAVD, OpenMDAO, ank},
  month = {June},
  title = {Trajectory Optimization of a Supersonic Air Vehicle with Thermal Fuel Management System},
  year = {2018}
}

@inproceedings{Jasa2019b,
  address = {Beijing, China},
  author = {John P. Jasa and Benjamin J. Brelje and Charles A. Mader and Joaquim R. R. A. Martins},
  booktitle = {World Congress of Structural and Multidisciplinary Optimization},
  keywords = {OpenMDAO, ccavd},
  month = {May},
  title = {Coupled Design of a Supersonic Engine and Thermal System},
  year = {2019}
}

@inproceedings{Jasa2019d,
  address = {San Diego, CA},
  author = {John P. Jasa and Justin S. Gray and Jonathan A. Seidel and Charles A. Mader and Joaquim R. R. A. Martins},
  booktitle = {57th AIAA Aerospace Sciences Meeting, AIAA SciTech Forum, 2019},
  doi = {10.2514/6.2019-0172},
  keywords = {CCAVD, OpenMDAO},
  month = {January},
  title = {Multipoint Variable Cycle Engine Design Using Gradient-based Optimization},
  year = {2019}
}

@inproceedings{Kaneko2022a,
  abstract = {The conceptual design process of aircraft starts by deciding the representative mission requirements, followed by optimization of design variables to satisfy the given requirements. However, selecting appropriate mission requirements is not an obvious task, particularly when designing the package delivery UAVs because UAVs must accommodate the various combinations of package weight and delivery distances. The complexity increases further when designing a heterogeneous fleet of UAVs that serves a large number of customers. In this work, we tackle this problem by solving the coupled design-operation optimization to find the optimal mission requirements and the optimal UAV designs simultaneously. We formulate this problem as mixed-integer nonlinear optimization and propose a sequential heuristic algorithm to solve the coupled problem. The benchmark study of the proposed algorithm against a non-convex branch-and-cut solver shows that the sequential heuristics are
effective. We also demonstrate that the simultaneous UAV design and routing optimization reduces the fleet acquisition cost by more than 10\% on average compared to the conventional baseline.},
  author = {Shugo Kaneko and Joaquim R. R. A. Martins},
  booktitle = {AIAA SciTech Forum},
  doi = {10.2514/6.2022-1503},
  keywords = {OpenMDAO, routing, UAV, xsede},
  month = {January},
  title = {Fleet Design Optimization of Package Delivery {UAV}s Considering Operations},
  year = {2022}
}

@inproceedings{Kaneko2023a,
  abstract = {Vertical takeoff and landing (VTOL) aircraft design requires consideration of an efficiency trade-off between various flight conditions, including hover, transition, and cruise. To capture this trade-off, we propose simultaneous optimization of aircraft conceptual design and takeoff trajectory. Design- trajectory optimization, also called open-loop control co-design, allows us to find the optimal aircraft design that balances the flight efficiency between various flight conditions for maximum system-level performance. In this paper, we maximize the payload weight capacity of a lift-plus-cruise unmanned aerial vehicle (UAV) for package delivery. As a result, simultaneous optimization increases the payload weight by up to 5.3\% compared to the conventional approach, which does not couple takeoff trajectory optimization to UAV conceptual design. We identify that the cruise speed and pusher motor sizing have a significant influence on takeoff trajectory. Simultaneous
optimization finds the optimal cruise speed and motor sizing that enables energy-efficient wing-borne climb, which is not always possible with conventional sequential optimization.},
  author = {Kaneko, Shugo and Martins, Joaquim R. R. A.},
  booktitle = {10th Autonomous VTOL Technical Meeting},
  keywords = {OpenMDAO, Dymos},
  month = {January},
  title = {Simultaneous Optimization of Conceptual Design and Takeoff Trajectory of a Lift-Plus-Cruise {UAV}},
  year = {2023}
}

@inproceedings{Roy2018a,
  address = {Kissimmee, FL},
  author = {Satadru Roy and William A. Crossley and Kenneth T. Moore and Justin S. Gray and Joaquim R. R. A. Martins},
  booktitle = {AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference},
  doi = {10.2514/6.2018-1647},
  keywords = {OpenMDAO},
  month = {January},
  title = {Next generation aircraft design considering airline operations and economics},
  year = {2018}
}

@inproceedings{Yildirim2019a,
  address = {Dallas, TX},
  author = {Anil Yildirim and Justin S. Gray and Charles A. Mader and Joaquim R. R. A. Martins},
  booktitle = {AIAA Aviation Forum},
  doi = {10.2514/6.2019-3455},
  keywords = {xsede, ank, aeroprop, beststudentpaper, openmdao},
  month = {June},
  title = {Aeropropulsive Design Optimization of a Boundary Layer Ingestion System},
  year = {2019}
}

@inproceedings{Yildirim2022b,
  author = {Anil Yildirim and Justin S. Gray and Joaquim R. R. A. Martins},
  booktitle = {Eleventh International Conference on Computational Fluid Dynamics},
  keywords = {ank, openmdao, aeroprop},
  month = {July},
  note = {ICCFD11-0702},
  title = {A Nonlinear {S}chur Complement Solver for {CFD}-Based Multidisciplinary Models},
  pdf = {https://www.iccfd.org/iccfd11/assets/pdf/papers/ICCFD11_Paper-0702.pdf},
  year = {2022}
}

@inproceedings{AbdulKaiyoom2023b,
  abstract = {Over-wing nacelle (OWN) configurations have two advantages over the traditional under-wing nacelle (UWN) configurations: 1. they make it easier to integrate high bypass ratio (BPR) and ultra-high BPR engines by removing ground clearance concerns, and 2. they significantly reduce noise because the wing blocks the noise of the fan and the jet. Despite their benefits, OWN technology is not widely used in real aircraft designs because of the challenges and lack of research in aeropropulsive integration of the propulsion system. In this work, we present multipoint aeropropulsive design optimizations of an OWN configuration to address several scenarios. To effectively design the propulsor in OWN, we consider on-design and off-design formulations of engine design concepts. In this work, we present one single-point optimization and three multipoint optimizations. In the multipoint optimizations, the objective is to minimize the shaft power at cruise conditions subject to
constraints. To compare the performance degradation of single-point optimization, we performed several sub-optimizations to reflect the multipoint cases. The single-point optimal design required additional 0.4\% shaft power across the cruise conditions when compared to the multipoint optimization with 3 cruise points. In addition, distortion-constrained and distortion-unconstrained optimizations were performed at the take-off scenario. By modifying the inlet shape of the nacelle, the distortion-constrained optimization effectively reduces the distortion in the take-off scenario at the outermost radial ring over the fan by penalizing the cruise performance. The multipoint optimizations in this work highlight a number of significant design effects. An effective design is produced by including the required flight conditions and specifying the proper objective and constraints in the OWN multipoint problem. These design optimization capabilities will be crucial in
determining the viability of novel propulsion concepts for next-generation OWN aircraft.},
  address = {San Diego, CA},
  author = {M. A. Saja Abdul-Kaiyoom and Anil Yildirim and Joaquim R. R. A. Martins},
  booktitle = {AIAA Aviation Forum},
  doi = {10.2514/6.2023-3588},
  keywords = {xsede, pleiades, ank, OpenMDAO, MPhys, ADflow, pyCycle},
  month = {June},
  title = {{RANS}-Based Multipoint Aeropropulsive Design Optimization of an Over-Wing Nacelle Configuration},
  year = {2023},
  pdf = {https://www.researchgate.net/profile/Joaquim-Martins-4/publication/371006356_RANS-Based_Multipoint_Aeropropulsive_Design_Optimization_of_an_Over-Wing_Nacelle_Configuration/links/646e742f6a0082273fa88ce9/RANS-Based-Multipoint-Aeropropulsive-Design-Optimization-of-an-Over-Wing-Nacelle-Configuration.pdf}
}

@inproceedings{Adler2023a,
  abstract = {Hydrogen aircraft have the potential to achieve greater climate impact reductions at a lower cost than aircraft powered by biofuels or other drop-in sustainable aviation fuels. But even as a liquid, hydrogen requires four times more volume than kerosene to store the same energy. Companies and researchers have suggested that the blended wing body configuration is well-suited to hydrogen because it can efficiently store the large fuel tanks. However, nobody has quantified this claim, at least publicly. We address this gap by comparing optimized kerosene and hydrogen versions of blended wing body and tube and wing aircraft. We find that the blended wing body configuration has only a small advantage for onboard hydrogen storage compared to a conventional tube and wing aircraft. Our models predict that with ambitious hydrogen tank technology assumptions, a hydrogen blended wing body uses 3.1\% more energy than a kerosene blended wing body, while the energy increase for a
tube and wing is 5.1\%. An advantage of the blended wing body is that the energy consumption increase when adapting from kerosene to hydrogen fuel appears to be far less sensitive than the tube and wing's to empty weight and drag changes. Because we only compare hydrogen and kerosene usage within the same configuration, a hydrogen blended wing body may still consume substantially less energy than a hydrogen tube and wing. However, these results do call into question the assumed tank storage benefit of a hydrogen-powered blended wing body aircraft.},
  author = {Eytan J. Adler and Joaquim R. R. A. Martins},
  booktitle = {AIAA Aviation 2023 Forum},
  doi = {10.2514/6.2023-4020},
  keywords = {OpenMDAO, OpenAeroStruct, OpenConcept},
  month = {June},
  title = {Blended wing body configuration for hydrogen-powered aviation},
  year = {2023},
  pdf = {https://www.researchgate.net/profile/Joaquim-Martins-4/publication/371033780_Blended_wing_body_configuration_for_hydrogen-powered_aviation/links/646f6c910ed3704822c065a4/Blended-wing-body-configuration-for-hydrogen-powered-aviation.pdf}
}

@inproceedings{AGray2023b,
  address = {San Diego, CA},
  author = {Alasdair C. Gray and Graeme J. Kennedy and Joaquim R. R. A. Martins},
  booktitle = {AIAA Aviation Forum},
  doi = {10.2514/6.2023-3316},
  keywords = {xsede, ank, OpenMDAO, MPhys},
  month = {June},
  title = {Geometrically Nonlinear High-fidelity Aerostructural Optimization Including Geometric Design Variables},
  year = {2023},
  pdf = {https://www.researchgate.net/profile/Joaquim-Martins-4/publication/371005992_Geometrically_Nonlinear_High-fidelity_Aerostructural_Optimization_Including_Geometric_Design_Variables/links/646e647bcde97a39292d4756/Geometrically-Nonlinear-High-fidelity-Aerostructural-Optimization-Including-Geometric-Design-Variables.pdf}
}

@inproceedings{Atma2023,
  abstract = {Advances in commercial propulsion technology led to the development of efficient high bypass ratio turbofan engines with larger overall pressure ratios and internal temperatures. Current trends suggest that geared ultra high bypass ratio turbofans are the next generation of commercial propulsion systems. Furthermore, the emphasis on decreasing emissions has driven the exploration of hydrogen-powered aircraft, adding to the already challenging design space. Carrying and burning hydrogen introduces complexity and weight penalties that we must offset using the fuel's thermodynamic and chemical properties. In this study, we model a closedloop water recirculation system with a zero-dimensional thermodynamic model and compare the benefits between Jet-A and hydrogen fuels. We perform a gradient-based optimization parameter sweep to explore the trade-offs between performance and emissions using both fuels with water recirculation. The results quantify the design space for
next-generation propulsion concepts that can take advantage of hydrogen fuel's thermodynamic properties to reduce emissions and improve performance.},
  address = {San Diego, CA},
  author = {Peter N. Atma and Andrew H. R. Lamkin and Joaquim R. R. A. Martins},
  booktitle = {AIAA Aviation Forum},
  doi = {10.2514/6.2023-4018},
  keywords = {openmdao},
  month = {June},
  title = {Comparing Hydrogen and Jet-A for an {N}+3 Turbofan with Water Recirculation using Gradient-Based Optimizaiton},
  year = {2023},
  pdf = {https://www.researchgate.net/profile/Joaquim-Martins-4/publication/371006087_Comparing_Hydrogen_and_Jet-A_for_an_N3_Turbofan_with_Water_Recirculation_using_Gradient-Based_Optimization/links/646e6b9ccde97a39292d486e/Comparing-Hydrogen-and-Jet-A-for-an-N-3-Turbofan-with-Water-Recirculation-using-Gradient-Based-Optimization.pdf}
}

@inproceedings{Backhaus2023a,
  abstract = {Multidisciplinary design optimization (MDO) plays a vital role in designing aircraft. Thus, the modularization of various disciplines is necessary to efficiently couple them in MDO or multidisciplinary design analysis (MDA). In this paper, we demonstrate how recent library extensions \cite{Backhaus_2021} lead to combining both the HPC ecosystem FlowSimulator, developed by DLR and partners, and the MDA/MDO framework, OpenMDAO, for a gradient-based MDO scenario of a generic static aeroelastic problem for a transport aircraft. In the MDO problem, the software architecture enables the optimal integration of high-fidelity workflows with central data management for high performance computing (HPC). To this end, we demonstrate how the FlowSimulator Data Manager (FSDM) enables the associated HPC simulation components to exchange massively parallel data in memory. Here, the algorithms provided by OpenMDAO---linear and nonlinear solution methods, and forward and backward
processing of sensitivity derivatives---operate on the infrastructure of the FlowSimulator HPC ecosystem. Based on the defined scenario, different solution strategies can be applied. In this work we define a nested aeroelastic coupling setup within a trim equilibrium constraint definition. In particular, we highlight how an efficient modularization of the individual disciplines supports an effective gradient assembly and thus makes them available to the individual solution hierarchies and strategies. With this approach, we show how it is possible to transform a baseline constrained optimization problem into an unconstrained optimization definition, while still ensuring the trim equilibrium through an implicit solution based on the Schur complement method.},
  address = {San Diego, CA},
  author = {Thomas Backhaus and M. A. Saja Abdul-Kaiyoom and Anil Yildirim and Arthur Stueck and Joaquim R. R. A. Martins},
  booktitle = {AIAA AVIATION Forum},
  doi = {10.2514/6.2023-3315},
  keywords = {OpenMDAO, Schur},
  month = {June},
  title = {Advancing Modularity and Framework Integration Level for Scalable High-Fidelity {MDO}},
  year = {2023}
}

@inproceedings{Hajdik2023b,
  abstract = {Aerodynamic shape optimization is a valuable tool for aircraft design, but geometric constraints have had limited design freedom or have failed to capture spatial integration requirements in sufficient detail. Using a detailed representation of an aircraft's systems and payload geometries in a packaging constraint allows for more accurate and higher-performance spatial integration. We use a previously developed general and differentible packaging constraint formulated for gradient-based optimization for aerodynamic shape optimization of a full aircraft configuration. We explore the design of the NASA tiltwing concept vehicle with aerodynamic shape optimization using packaging constraints to examine the tradeoffs between aerodynamics and mission performance. The resulting design can be more targeted to our design requirements than one that can be achieved with conventional geometric constraints.},
  address = {San Diego, CA},
  author = {Hannah M. Hajdik and Bernardo Pacini and Anil Yildirim and Benjamin J. Brelje and Joaquim R. R. A. Martins},
  booktitle = {AIAA Aviation Forum},
  doi = {10.2514/6.2023-3589},
  keywords = {OpenMDAO, MPhys, packaging},
  month = {June},
  title = {Combined systems packaging and aerodynamic shape optimization of a full aircraft configuration},
  year = {2023},
  pdf = {https://www.researchgate.net/profile/Hannah_Hajdik/publication/371071558_Combined_systems_packaging_and_aerodynamic_shape_optimization_of_a_full_aircraft_configuration/links/6470ef476fb1d1682b0d13bb/Combined-systems-packaging-and-aerodynamic-shape-optimization-of-a-full-aircraft-configuration.pdf}
}

@inproceedings{Lamkin2023,
  abstract = {To improve performance and reduce fuel consumption, we must address tightly connected aeropropulsive effects in the development of new and existing propulsion technologies. Aeropropulsive design optimization considers the multidisciplinary coupled interactions between aerodynamics, thermodynamics, and geometry. Mixed-fidelity aeropropulsive methods integrate high-fidelity aerodynamic solvers with zero-dimensional thermodynamic cycle modeling. Combined with gradient-based optimization, this approach is a computationally efficient design tool that can accommodate large design spaces with many design variables and constraints. Previously, we developed a novel hybrid aeropropulsive coupling method for turbofan engines and demonstrated its feasibility using a single-design-point problem. In this work, we improve upon the prior approach and perform the first successful coupled aeropropulsive optimization of a high-bypass turbofan. We analyze the optimized turbofan design
and validate the corrections to the hybrid coupling scheme. The updated coupling methods are a significant advancement in aeropropulsive optimization that enable the design of tightly integrated propulsion systems considering thermodynamic and aerodynamic performance.},
  address = {San Diego, CA},
  author = {Andrew H. R. Lamkin and Anil Yildirim and Joaquim R. R. A. Martins and Nathan A. Wukie},
  booktitle = {AIAA Aviation Forum},
  doi = {10.2514/6.2023-3591},
  keywords = {openmdao, mphys, ank, aeroprop, pleiades},
  month = {June},
  title = {Advancements in Coupled Aeropropulsive Design Optimization for High-Bypass Turbofan Engines},
  year = {2023},
  pdf = {https://www.researchgate.net/profile/Joaquim-Martins-4/publication/371006322_Advancements_in_Coupled_Aeropropulsive_Design_Optimization_for_High-Bypass_Turbofan_Engines/links/646e6b3b37d6625c002e423e/Advancements-in-Coupled-Aeropropulsive-Design-Optimization-for-High-Bypass-Turbofan-Engines.pdf}
}

@inproceedings{Seraj2023a,
  abstract = {Three-surface configurations offer theoretical drag benefits over two-surface configurations, but the literature is unclear on what is the best configuration for a supersonic aircraft. This work uses trim-constrained drag minimization to compare the trim drag for three-surface, canard, and conventional variants of a supersonic transport aircraft. We first use RANS-based optimization to determine the minimum trim drag for a fixed planform geometry at a subsonic takeoff condition and a supersonic cruise condition. The three-surface configuration has the lowest trim drag at the supersonic condition. The canard and three-surface configurations have comparable trim drag at the subsonic condition. We then construct a supersonic buildup model to study the effects of variable trim surface sizing. When the trim surface spans are included as design variables, the design for minimum supersonic drag has practically no tail and a canard sized at 36% of the wing half-span. These
results suggest that a canard configuration is best for supersonic trim drag.},
  author = {Sabet Seraj and Joaquim R. R. A. Martins},
  booktitle = {AIAA Aviation Forum},
  doi = {10.2514/6.2023-3472},
  keywords = {ank, scalos, OpenMDAO},
  month = {June},
  title = {Minimum Trim Drag for a Three-Surface Supersonic Transport Aircraft},
  year = {2023},
  pdf = {https://www.researchgate.net/profile/Sabet-Seraj/publication/371156075_Minimum_Trim_Drag_for_a_Three-Surface_Supersonic_Transport_Aircraft/links/647604f859d5ad5f9c879760/Minimum-Trim-Drag-for-a-Three-Surface-Supersonic-Transport-Aircraft.pdf}
}