Simao Marques

Dr Simão Marques


Senior Lecturer
PhD, BEng(Hons) Aeronautical Engineering

Academic and research departments

Department of Mechanical Engineering Sciences.

Research

Research interests

Research projects

Research collaborations

Courses I teach on

Undergraduate

My publications

Publications

W. Yao and S. Marques (2017). Model reduction for nonlinear aerodynamics and aeroelasticity using a Discrete Empirical Interpolation Method
View abstract
A novel surrogate model is proposed in lieu of computational-fluid-dynamics solvers, for fast nonlinear aerodynamic and aeroelastic modeling. A nonlinear function is identified on selected interpolation points by a discrete empirical interpolation method. The flowfield is then reconstructed using a least-square approximation of the flow modes extracted by proper orthogonal decomposition. The aeroelastic reduced-order model is completed by introducing a nonlinear mapping function between displacements and the discrete empirical interpolation method points. The proposed model is investigated to predict the aerodynamic forces due to forced motions using a NACA 0012 airfoil undergoing a prescribed pitching oscillation. To investigate aeroelastic problems at transonic conditions, a pitch/plunge airfoil and a cropped delta wing aeroelastic models are built using linear structural models. The presence of shock waves triggers the appearance of limit-cycle oscillations, which the model is able to predict. For all cases tested, the new reduced-order model shows the ability to replicate the nonlinear aerodynamic forces and structural displacements and reconstruct the complete flowfield with sufficient accuracy at a fraction of the cost of full-order computational-fluid-dynamics model.A novel surrogate model is proposed in lieu of computational-fluid-dynamics solvers, for fast nonlinear aerodynamic and aeroelastic modeling. A nonlinear function is identified on selected interpolation points by a discrete empirical interpolation method. The flowfield is then reconstructed using a least-square approximation of the flow modes extracted by proper orthogonal decomposition. The aeroelastic reduced-order model is completed by introducing a nonlinear mapping function between displacements and the discrete empirical interpolation method points. The proposed model is investigated to predict the aerodynamic forces due to forced motions using a NACA 0012 airfoil undergoing a prescribed pitching oscillation. To investigate aeroelastic problems at transonic conditions, a pitch/plunge airfoil and a cropped delta wing aeroelastic models are built using linear structural models. The presence of shock waves triggers the appearance of limit-cycle oscillations, which the model is able to predict. For all cases tested, the new reduced-order model shows the ability to replicate the nonlinear aerodynamic forces and structural displacements and reconstruct the complete flowfield with sufficient accuracy at a fraction of the cost of full-order computational-fluid-dynamics model.
W. Yao and S. Marques (2015). Prediction of Transonic Limit-Cycle Oscillations Using an Aeroelastic Harmonic Balance Method
View abstract
This work proposes a novel approach to compute transonic Lim it Cycle Oscillations (LCOs) using high fidelity analysis. CFD based Harmonic Balance (HB) methods have proven to be efficient tools to predict periodic phenomena. Th is paper’s contribution is to present a new methodology to determine the unknown freq uency of oscillations, enabling HB methods to accurately capture LCOs ; this is achieved by defining a fre- quency updating procedure based on a coupled CFD/CSD (Compu tational Structural Dynamics) HB formulation to find the LCO condition. A pitch/p lunge aerofoil and delta wing aerodynamic and respective linear structural mo dels are used to validate the new method against conventional time-domain simulation s. Results show con- sistent agreement between the proposed and time-marching me thods for both LCO amplitude and frequency, while producing at least one order of magnitude reduction in computational time.
R. Hayes, S. Marques (2014). Prediction of Limit Cycle Oscillations under Uncertainty using a Harmonic Balance Method
View abstract
The Harmonic Balance method is an attractive solution for computing periodic responses and can be an alternative to time domain methods, at a reduced computational cost. The current paper investigates using a Harmonic Balance method for simulating limit cycle oscillations under uncertainty. The Harmonic Balance method is used in conjunction with a non-intrusive polynomial-chaos approach to propagate variability and is validated against Monte Carlo analysis. Results show the potential of the approach for a range of nonlinear dynamical systems, including a full wing configuration exhibiting supercritical and subcritical bifurcations, at a fraction of the cost of performing time domain simulations.
S. Marques, K. J. Badcock, H. H. Khodaparast, and J. E. Mottershead (2012). How Structural Model Variability Influences Transonic Aeroelastic Stability
Timme, S. , Marques, S. & Badcock, K., (2011). Transonic aeroelastic stability analysis using a Kriging–based Schur complement formulation
K.J. Badcock, S. Timme, S. Marques, H. Khodaparast, M. Prandina, J.E. Mottershead, A. Swift, A. Da Ronch, M.A. Woodgate (2011). Transonic aeroelastic simulation for instability searches and uncertainty analysis
M. Ghoreyshi, K. J. Badcock, A. Da Ronch, S. Marques, A. Swift, N. Ames (2011). Framework for Establishing Limits of Tabular Aerodynamic Models for Flight Dynamics Analysis
S. Marques, K. J. Badcock, H. H. Khodaparast, J. E. Mottershead (2010). Transonic Aeroelastic Stability Predictions Under the Influence of Structural Variability
Marques, S. , Badcock, K. J. , Gooden, J. H. M. , Gates, S. & Maybury, W., (2010). Validation study for prediction of iced aerofoil aerodynamics
Dheeraj Agarwal, Trevor Robinson, Cecil Armstrong, Simao Marques, Ilias Vasilopoulos, Marcus Meyer (2017). Parametric design velocity computation for CAD-based design optimization using adjoint methods
R. Hayes, R. Dwight, S. Marques (2017). Reducing parametric uncertainty in limit-cycle oscillation computational models
W. Yao, S. Marques (2018). A Harmonic Balance Method for Nonlinear Fluid Structure Interaction Problems
View abstract
Over the past decade the Harmonic-Balance technique has been established as a viable alternative to direct time integration methods to predict periodic aeroelastic instabilities. This article reports the progress made in using a frequency updating procedure, based on a coupled fluid-structural solver using the Harmonic-Balance formulation. In particular, this paper presents an efficient implicit time-integrator that accelerates the convergence of the structural equations of motion to the final solution. To demonstrate the proposed approached, the paper includes a detailed investigation of the impact of input parameters and exercises the method for two types of fluid-structural nonlinear instabilities: transonic limit-cycle oscillations and vortex-induced vibrations.
Weigang Yao, Simao Marques (2017). Application of a high-order CFD harmonic balance method to nonlinear aeroelasticity
View abstract
An Aeroelastic-Harmonic Balance (A-HB) formulation of the Euler flow equations using a high-order spatial discretization scheme coupled with structural dynamic equations is proposed. The main objective of this new approach is to dramatically reduce the computational cost required to predict unsteady, periodic problems such as limit cycle oscillations (LCO). To this end, a new solver based on the Monotonicity Preserving limiter together with the AUSM+-up flux function is developed for the harmonic balance equations. The use of high-order CFD schemes allows the reduction of the number of degrees of freedom required to achieve a given desired accuracy, with respect to lower order schemes. In this paper, the reduction in degrees of freedom of the fluid system is exploited in the context of a CFD based Harmonic-Balance framework using a frequency updating procedure to determine the limit cycle conditions. The standard A-HB methodology has shown over one order of magnitude speed-up over time-marching methods; by employing the proposed high-order scheme in conjunction with coarser grids, the LCO computational time is halved without compromising accuracy.