Martin Goland

Bio: Martin Goland is an academic researcher from Southwest Research Institute. The author has contributed to research in topics: Aeroelasticity & Potential flow. The author has an hindex of 1, co-authored 2 publications receiving 640 citations.

Principles of aeroelasticity

Abstract: Keywords: aeroelasticite ; instationnaire ; structures Reference Record created on 2005-11-18, modified on 2016-08-08

Shear Lag Solutions for Sheet-Stringer Panels by Means of a Hydrodynamic Analogy

Abstract: An analogy is established between the stress flow in flat sheetstringer panels and the plane potential flow of an incompressible fluid. The sheet-stringer panels are presumed to be "shear lag" structures carrying essentially longitudinal loads (parallel to the stringers), and the effects of lateral stresses and deflections are ignored. I t is shown that the hydrodynamic analogy consists of a direct relationship between longitudinal stress and the longitudinally directed component of fluid velocity. Shear stress bears a direct relationship to the laterally directed component of fluid velocit}^. In transferring from the sheet-stringer panel to the equivalent flow, an afnne transformation of coordinates, and, hence, of the panel boundaries, must be made. A discussion is given of the corresponding boundary conditions for the stress flow and the fluid flow. A boundary free of normal stress is equivalent to flow past a solid wall. I t is also shown how rigidly constrained boundaries can be dealt with in re la t ive^ simple fashion. Problems of reinforcement around cutouts in the sheet-stringer panel are also discussed. The use of the analogy is demonstrated in several examples, including the stress concentration around elliptic cutouts, with free and constrained boundaries, in large panels under uniform tension. Also studied is the case of a concentrated longitudinal force applied at the center of a large panel.

Balanced Model Reduction via the Proper Orthogonal Decomposition

Abstract: A new method for performing a balanced reduction of a high-order linear system is presented. The technique combines the proper orthogonal decomposition and concepts from balanced realization theory. The method of snapshotsisused to obtainlow-rank,reduced-rangeapproximationsto thesystemcontrollability and observability grammiansineitherthetimeorfrequencydomain.Theapproximationsarethenusedtoobtainabalancedreducedorder model. The method is particularly effective when a small number of outputs is of interest. It is demonstrated for a linearized high-order system that models unsteady motion of a two-dimensional airfoil. Computation of the exact grammians would be impractical for such a large system. For this problem, very accurate reducedorder models are obtained that capture the required dynamics with just three states. The new models exhibit far superiorperformancethanthosederived using a conventionalproperorthogonal decomposition. Although further development is necessary, the concept also extends to nonlinear systems.

Ordinary Differential Equations with Applications

Abstract: Introduction to Ordinary Differential Equations * Linear Systems and Stability of Nonlinear Systems * Applications * Hyperbolic Theory * Continuation of Periodic Solutions * Homoclinic Orbits, Melnikov?s Method, and Chaos * Averaging * Local Bifurcation * References * Index.

A Modern Course in Aeroelasticity

Abstract: Static Aeroelasticity.- Dynamic Aeroelasticity.- Nonsteady Aerodynamics of Lifting and Non-Lifting Surfaces.- Stall Flutter.- Aeroelasticity in Civil Engineering.- Aeroelastic Response of Rotorcraft.- Aeroelasticity in Turbomachines.- Modeling of Fluid-Structure Interaction.- Experimental Aeroelasticity.- Nonlinear Aeroelasticity.- Aeroelastic Control.- Modern Analysis for Complex and Nonlinear Unsteady Flows in Turbomachinery.

Introduction to Structural Dynamics and Aeroelasticity

Abstract: Keywords: aeroelasticite ; structure : dynamique Reference Record created on 2005-11-18, modified on 2016-08-08