References of "Hickey, Daryl"
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See detailModel order reduction techniques for thermomechanical systems with nonlinear radiative heat transfer using proper orthogonal decomposition
Hickey, Daryl ULg; Hoffait, Sébastien ULg; Rothkegel Ide, José Ignacio ULg et al

in Proceedings of ISMA 2010 (2010, September)

Analysing large scale, nonlinear, multiphysical, dynamical structures, by using mathematical modelling and simulation, e.g. Finite Element Modelling (FEM), can be computationally very expensive ... [more ▼]

Analysing large scale, nonlinear, multiphysical, dynamical structures, by using mathematical modelling and simulation, e.g. Finite Element Modelling (FEM), can be computationally very expensive, especially if the number of degrees-of-freedom is high. This paper develops modal reduction techniques for such nonlinear multiphysical systems. The paper focuses on Proper Orthogonal Decomposition (POD), a multivariate statistical method that obtains a compact representation of a data set by reducing a large number of interdependent variables to a much smaller number of uncorrelated variables. A fully coupled, thermomechanical model consisting of a multilayered, cantilever beam is described and analysed. This linear benchmark beam is then extended to incorporate an external box. The nonlinear radiative exchanges between the beam and the external box are analysed and a reduction procedure is proposed for this fully coupled, nonlinear, multiphysical, thermomechanical system. Two alternative approaches to the reduction are investigated, a monolithic scaled approach and a partitioned approach that treats the individual physical modes separately. [less ▲]

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See detailAnalysis of dynamic response of a very flexible Delta wing model in a wind tunnel
Barbason, Mathieu ULg; Andrianne, Thomas ULg; Hickey, Daryl ULg et al

in Proceedings of the 2009 International Forum on Aeroelasticity and Structural Dynamics (2009, July)

Limit cycle oscillations involving Delta wings are an important area of research in modern aeroelasticity. Such phenomena can be the result of geometric nonlin- earity, aerodynamic nonlinearity or under ... [more ▼]

Limit cycle oscillations involving Delta wings are an important area of research in modern aeroelasticity. Such phenomena can be the result of geometric nonlin- earity, aerodynamic nonlinearity or under-wing store nonlinearity. In this paper, a flexible half-Delta wing without stores is tested in a low speed wind tunnel in order to investigate its dynamic response. It is found that, at several combinations of airspeed and angle of attack, the wing undergoes high amplitude limit cycle oscillations. Three types of such oscillations are observed. Type 1 oscillations occur only at low angles of attack and are the result of a Hopf-type bifurcation. Type 2 limit cycle oscillations occur at intermedi- ate angles of attack and are the result of an atypical bifurcation. In other words, these oscillations appear as the airspeed is increased but disappear at even higher airspeeds. Type 3 oscillations occur at even higher angles of attack. A bispectrum analysis shows that type 3 limit cycle oscillations feature quadratic phase coupling. No such coupling was measured for type 2 oscillations, leading to the conclusion that the nonlinearity must be of higher order. [less ▲]

Detailed reference viewed: 96 (37 ULg)