Joaquim R. R. A. Martins

Joaquim R. R. A. Martins
University of Michigan | U-M · Department of Aerospace Engineering

PhD

About

346
Publications
274,988
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
12,908
Citations
Additional affiliations
September 2009 - August 2015
University of Michigan
Position
  • Professor (Associate)
November 2002 - August 2009
University of Toronto
Position
  • Associate Professor, Canada Research Chair in MDO (Tier 2)
September 1997 - October 2002
Stanford University
Position
  • Research Assistant
Education
September 1991 - June 1995
Imperial College London
Field of study
  • Aeronautical Engineering

Publications

Publications (346)
Article
Full-text available
Multidisciplinary design optimization is a field of research that studies the application of numerical optimization techniques to the design of engineering systems involving multiple disciplines or components. Since the inception of multidisciplinary design optimization, various methods (architectures) have been developed and applied to solve multi...
Article
Full-text available
Multidisciplinary design optimization (MDO) is concerned with solving design problems involving coupled numerical models of complex engineering systems. While various MDO software frameworks exist, none of them take full advantage of state-of-the-art algorithms to solve coupled models efficiently. Furthermore, there is a need to facilitate the comp...
Book
Full-text available
Based on course-tested material, this rigorous yet accessible graduate textbook covers both fundamental and advanced optimization theory and algorithms. It covers a wide range of numerical methods and topics, including both gradient-based and gradient-free algorithms, multidisciplinary design optimization, and uncertainty, with instruction on how t...
Article
Full-text available
The adjoint method is used for high-fidelity aerodynamic shape optimization and is an efficient approach for computing the derivatives of a function of interest with respect to a large number of design variables. Over the past few decades, various approaches have been used to implement the adjoint method in computational fluid dynamics solvers. How...
Article
Full-text available
Despite considerable research on aerodynamic shape optimization, there is no standard benchmark problem allowing researchers to compare results. This work addresses this issue by solving a series of aerodynamic shape optimization problems based on the Common Research Model wing benchmark case defined by the Aerodynamic Design Optimization Discussio...
Conference Paper
Full-text available
The aerodynamic design of aircraft often involves evaluating flow conditions that span low subsonic to transonic, or even supersonic Mach numbers. Compressible flow solvers are a natural choice for such design problems, but these solvers encounter reduced accuracy and efficiency at low Mach numbers. In addition, simulations with supersonic conditio...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2022-3357.vid The next-generation aircraft are trending towards more flexible wings that make them more prone to flutter, or more general, limit cycle oscillation (LCO). Thus, when conducting a multidisciplinary design optimization (MDO) using the gradient-based method, computing the LCO derivative...
Conference Paper
Full-text available
Aerodynamic shape optimization has become a well-established process, with designers routinely performing wing and full aircraft optimizations with hundreds of geometric design variables. However, with increased geometric design freedom comes increased optimization difficulty. These optimizations tend to converge very slowly, often taking many hund...
Conference Paper
View Video Presentation: https://doi.org/10.2514/6.2022-3930.vid The plate-fin heat exchanger is common in aerospace applications because of its small size and lightweight. Heat exchangers are vital to aircraft applications such as jet engines, environmental control systems, and thermal management systems for electric components. The thermal manage...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2022-3384.vid This paper presents the results of the optimisation of aerofoils designed for the blades of a vertical axis wind turbine. The aerofoils are symmetrical and have thickness values of 27%, 33% and 50\%, with respect to the chord length. The aerofoils are optimised using ADflow, an open-s...
Conference Paper
Full-text available
When designing aircraft, avoiding dynamic aeroelastic instabilities such as flutter is a key requirement. One way to meet this requirement is to use a multidisciplinary design optimization subject to a flutter constraint. To date, flutter-constrained design optimizations have used geometrically linear models, that do not accurately predict flutter...
Article
Full-text available
Aerodynamic shape optimization based on computational fluid dynamics (CFD) requires three steps: updating the geometry based on the design variables, updating the CFD surface mesh for the new geometry, and updating the CFD volume mesh based on the new surface mesh. While there are many tools available for the first and third steps, the methods avai...
Article
Full-text available
Electrified aircraft benefit from the versatile ways electric motors can be integrated with an airframe. However, thermal management is needed to move waste heat out of the motors because the heat is not expelled with the exhaust as in a conventional engine. Plate-fin, fin, and surface heat exchangers are incorporated as air-side heat exchangers fo...
Article
Full-text available
Transonic buffet is undesirable because it causes vibration, and constraining buffet is crucial in transonic wing design. However, there is still a lack of accurate and efficient buffet formulation to impose the constraint. This work proposes a physics-based data-driven buffet analysis model generalizable for airfoil and wing shapes. The model is t...
Article
Full-text available
Electrified aircraft propulsion enables new aircraft designs with fewer emissions. One challenge of electrified architectures is handling the electrical components’ waste heat. This is because batteries and other electrical components are sensitive to high temperatures and accumulate heat within their structure. In this work, we investigate using a...
Preprint
Full-text available
This paper introduces a control co-design (CCD) framework to simultaneously explore the physical parameters and control spaces for a hydro-kinetic turbine (HKT) rotor optimization. The optimization formulation incorporates a coupled dynamic-hydrodynamic model to maximize the rotor power efficiency for various time-variant flow profiles. The open-lo...
Article
Full-text available
Multifidelity design optimization is a strategy that can reduce the high computational cost in cases where the high-fidelity model is too expensive to use directly in optimization. However, current multifidelity approaches cannot handle the high-dimensional problems commonly encountered in industrial settings. Furthermore, they cannot accommodate a...
Article
Full-text available
Ensuring the safe operation of new supersonic transport aircraft requires understanding their stability during takeoff and landing. These phases involve flying at subsonic speeds and high angles of attack, where the aerodynamics are characterized by unsteady vortical flow. This work assesses the accuracy of Reynolds-averaged Navier-Stokes (RANS) an...
Article
Antony Jameson pioneered CFD-based aerodynamic design optimization in the late 1980s. In addition to developing the fundamental theory, Jameson implemented that theory in codes that were practical enough to be used in industry. As a result of Jameson’s seminal efforts, a research community has been established in aerodynamic design optimization. Th...
Preprint
Full-text available
Machine learning (ML) has been increasingly used to aid aerodynamic shape optimization (ASO), thanks to the availability of aerodynamic data and continued developments in deep learning. We review the applications of ML in ASO to date and provide a perspective on the state-of-the-art and future directions. We first introduce conventional ASO and cur...
Article
Full-text available
The inclusion of transition to turbulence effects in computational fluid dynamics (CFD) simulations makes it possible to design laminar flow airframes. It also increases the level of physical representations for simulations of standard airframes because laminar flow regions may be present in parts of the aircraft in multiple flight conditions. Modi...
Preprint
Limit cycle oscillations (LCO) can be supercritical or subcritical. The supercritical response is benign, while the subcritical response can be destructive. It is desirable to avoid subcritical responses by enforcing LCO stability through design optimization constraints. However, there is a need for a computational approach that can model this inst...
Article
Full-text available
Boundary-layer ingestion (BLI) offers the potential for significant fuel burn reduction by exploiting tightly coupled aeropropulsive effects. NASA’s Single-aisle Turboelectric Aircraft with Aft Boundary-Layer propulsion (STARC-ABL) concept employs BLI on an electrically powered tail cone thruster to take advantage of the technology on what is other...
Article
Full-text available
Eigenvalue and eigenvectors are essential metrics to characterize dynamic system behavior and stability. When performing gradient-based design optimization, derivatives of these metrics are required. Analytic forward algorithmic differentiation (FAD) for a self-adjoint generalized eigenproblem has been a useful technique. However, reverse algorithm...
Article
Full-text available
Imperfectly scaled models are commonplace in aerodynamics and hydrodynamics because few facilities can meet all the flow and structural scaling requirements. The objectives of this work are to (1) derive and numerically validate scaling relations for the steady-state and dynamic hydroelastic response and stability of hydrodynamic composite lifting...
Conference Paper
Full-text available
The decarbonization of the electric grid is a fundamental technological and socio-economical challenge to address the looming threat of climate change. The reduction of the levelized cost of energy is a critical step to expand the application of carbon-free technologies that rely on high-potential, renewable energy sources such as wind power. Advan...
Conference Paper
Full-text available
Designing supersonic transport aircraft requires accounting for performance and stability and high-speed and low-speed conditions. Previous work demonstrated that there is a trade-off between high-speed performance and low-speed stability. Numerical optimization presents the opportunity to obtain the best high-speed performance while enforcing stab...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2022-1290.vid As demand grows for wind turbines with larger blades, the design of future wind turbines must account for multi-physical interactions and an ever-increasing number of design load conditions. One aspect, aerostructural coupling, calls for design tools that are both accurate and computa...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2022-1503.vid 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...
Conference Paper
Full-text available
In the past, aerostructural optimizations have used a single or small number of analyses in cruise to roughly estimate mission performance. This is accurate enough for long missions where the majority of time is spent near a single flight condition in cruise. But for regional and narrowbody aircraft, the fuel burn in climb is a substantial portion...
Conference Paper
View Video Presentation: https://doi.org/10.2514/6.2022-1867.vid Computational fluid dynamics solvers that use structured meshes are faster per degree of freedom and often more efficient than unstructured solvers. For applications such as aerodynamic shape optimization, where hundreds of flow solution are required, structured solvers are generally...
Conference Paper
Full-text available
Higher-aspect-ratio lightweight wings can make aircraft more energy efficient thanks to induced drag reduction. Because such wings exhibit large deflections, affecting the flutter onset, design optimization using linear flutter analysis is inadequate. To address this issue, we develop a framework for including a geometrically nonlinear flutter cons...
Preprint
Full-text available
We present a parsimonious surrogate framework for learning high dimensional parametric maps from limited training data. The need for parametric surrogates arises in many applications that require repeated queries of complex computational models. These applications include such "outer-loop" problems as Bayesian inverse problems, optimal experimental...
Article
Full-text available
This paper is written to honor Raphael T. Haftka’s seminal contributions to multidisciplinary design optimization. We focus on those contributions that directly impacted our research, namely: the adjoint method for computing derivatives, wing aerostructural design optimization, and architectures for multidisciplinary design optimization. For each o...
Article
Full-text available
Discrete multi-load truss sizing optimization (MTSO) problems are challenging to solve due to their combinatorial, nonlinear, and non-convex nature. This study highlights two important characteristics of the feasible set of MTSO problems considered here, in which force balance equations, Hooke’s law, yield stress, bound constraints on displacements...
Article
Full-text available
Discrete variable topology optimization problems are usually solved by using solid isotropic material with penalization (SIMP), genetic algorithms (GA), or mixed-integer nonlinear optimization (MINLO). In this paper, we propose formulating discrete ply-angle and thickness topology optimization problems as a mixed-integer second-order cone optimizat...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2021-3051.vid The proper orthogonal decomposition (POD) based reduced-order model (ROM) has been an effective tool for flow field prediction in the engineering industry. The sample selection in the design space for POD basis construction affects the ROM performance sensitively. Adaptive sampling ca...
Conference Paper
Full-text available
Urban air mobility vehicles have taken form as advanced rotorcraft with sets of wings, rotors, canards, and other appendages. Noise generation is an important technical barrier that must be addressed to prevent these vehicles from causing excessive disturbance to the communities they are intended to service. There is a need for efficient and low-fi...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2021-2612.vid Ensuring the safe operation of new supersonic transport aircraft requires understanding their stability during takeoff and landing. These phases involve flying at subsonic speeds and high angles of attack, where the aerodynamics are characterized by unsteady vortical flow. In this wor...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2021-3032.vid New aircraft concepts increasingly rely on non-traditional propulsion systems to achieve lower energy consumption. These non-traditional technologies, such as boundary layer ingestion or distributed electric propulsion, require tight integration of the propulsion system to the airfram...
Conference Paper
Full-text available
View Video Presentation: https://doi.org/10.2514/6.2021-3061.vid We have seen the emerging applications of deep neural networks for flow field predictions in the past few years. Most of the efforts rely on the increased complexity of the model itself or take advantage of novel network architectures, such as convolutional neural networks (CNN). Howe...
Article
Full-text available
Natural laminar flow is one of the most promising ways to reduce the drag of future aircraft configurations. However, there is a lack of efficient tools for performing shape optimization considering laminar-to-turbulent transition. This is in part because including crossflow instabilities in the optimization is challenging. This paper addresses thi...
Conference Paper
Full-text available
The performance and scalability of computational fluid dynamics (CFD) solvers are essential for many applications, including multidisciplinary design optimization. With the evolution of high-performance computing resources such as Intel's Knights Landing and Skylake architectures in the Stampede2 cluster, CFD solver performance can be improved by mo...
Article
Full-text available
Flutter and limit cycle oscillation (LCO) are important phenomena that need to be considered in aircraft design. Previous harmonic-balance-based flutter and LCO prediction methods either have low linear convergence rates or require expensive Newton steps to achieve quadratic convergence. In this paper, we propose a preconditioned, Jacobian-free, co...
Article
Full-text available
Design and manufacturing technologies have promoted the use of composites in hydrodynamic lifting surfaces. Composites, even with state-of-the-art coatings, are susceptible to cavitation erosion damage. This work aims to design a cavitation-free composite lifting surface to maximize efficiency while ensuring structural integrity. We optimize a cano...
Article
Full-text available
[Update 2021-10-10: Added an erratum to the full-text file here with corrections to the published validation results.] The recent growth of interest in hybrid-electric and fully electric aircraft has led to a renewed focus on the design and optimization of propeller aircraft. Considering propeller–wing interaction provides the opportunity to desig...
Article
Full-text available
Introduced in 1993, the DIRECT global optimization algorithm provided a fresh approach to minimizing a black-box function subject to lower and upper bounds on the variables. In contrast to the plethora of nature-inspired heuristics, DIRECT was deterministic and had only one hyperparameter (the desired accuracy). Moreover, the algorithm was simple,...
Article
Full-text available
The classical aeroelastic scaling theory used to design scaled models is based on the assumption that complete flow similarity exists between the full aircraft and the scaled model. When this condition is satisfied, the scaling problem of the model can be treated as a structural design problem only, where the scaled aerodynamic shape is preserved....
Article
Full-text available
Aerodynamic optimization based on computational fluid dynamics (CFD) is a powerful design approach because it significantly reduces the design time compared with the human manual design. However, CFD-based optimization can still take hours to converge because it requires repeatedly running computationally expensive flow simulations. To further shor...
Article
Full-text available
The inclusion of transition-to-turbulence effects in Computational Fluid Dynamics (CFD) simulations is essential to accurately predict drag reduction from the use of laminar flow technologies. The parabolized stability equations (PSE) method takes into account nonlocal and nonparallel effects on boundary layer dynamics. Its computational cost compa...
Conference Paper
Full-text available
Hydrogen has been identified as a potential fuel for air transportation without carbon emissions. Hydrogen contains much higher energy per unit mass than any conceivable rechargeable battery, potentially making longer-range missions possible than pure electric configurations. However, hydrogen's low volumetric energy density presents practical chal...
Conference Paper
Full-text available
Over the past decade, advances in multidisciplinary design optimization (MDO) have enabled the optimization of aircraft wings using high-fidelity simulations of their coupled aerodynamic and structural behavior. However, as their aspect-ratios increase, these wings increasingly exhibit geometrically nonlinear behavior that cannot be correctly model...
Conference Paper
Aerospace engineering design often needs to consider unsteady flow phenomena such as vortex shedding, unsteady wakes, and flow oscillation. The flow unsteadiness poses challenges for both analysis and derivative computation for gradient-based design optimization. This is because unsteady flow analysis and derivative computation require repeatedly s...
Conference Paper
Full-text available
Boundary layer ingestion (BLI) offers the potential for significant fuel burn reduction by exploiting strong aeropropulsive interactions. NASA's STARC-ABL concept uses an electrically powered BLI tail cone thruster on what is otherwise a conventional airframe. Despite this conventional airframe, aeropropulsive integration is critical to the perform...
Article
Full-text available
The second-generation of supersonic civil transport has to match ambitious targets in terms of efficiency to be economically and environmentally viable. CFD-based design optimization offers a powerful approach to address the complex tradeoffs intrinsic to this novel configuration. We apply this approach to the design of airfoils and wings at both s...