This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Considerations on an Integral Flight Physics Model with Application to Loads Analysis
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 18, 2011 by SAE International in United States
Annotation ability available
Increasing technical dependencies between the engineering disciplines driving the overall design of an aircraft and improving optimization techniques that make use of these interactions blur the lines between distinct disciplines and create demand for a harmonized flight physics model.
In this paper we present considerations on a general framework that allows the representation of the equations and data from various domains in an object-oriented and scalable structure. Emphasis is put on the loads aspect with the distinct fields of gust loads, maneuver loads and ground loads analysis, which are essential for structural design.
A fully generic, grid based data structure is presented, which is suitable for models of different granularity and applicability. All data is represented in this general form independent of its origin and may be transformed in between the different representations using splines. Coordinate transformations are handled automatically. It accepts local sub-models that are combined to form a complete aircraft representation.
This integral model can be applied to all disciplines and their combination if necessary. For example, a nonlinear maneuver can be combined with a linear gust calculation. However, in a fully nonlinear model, several disturbing effects of these nonlinearities in a distinct calculation can be observed as it includes physical limitations from another discipline.
As a work around, a calculation framework is presented that formalizes a very general description of a calculation. Examples for calculations are trim solutions and time or frequency domain simulations on differential equations formulated in different frameworks or programming languages and can be expressed in an implicit or an explicit way. The calculations can be combined in a tree-like database, where each calculation step is followed by an analysis step. If an operation is not suitable for the aircraft model due to a limitation implicitly posed by the nonlinear description, this may be detected and an alternative calculation can be performed fully automatically, such that the considered situation still contributes to the overall result. This is important for uncertainty analysis and multidisciplinary optimization, where a considered result at least needs to be continuous for a wide range of parameters.
CitationScharpenberg, M., Kier, T., and Taules, L., "Considerations on an Integral Flight Physics Model with Application to Loads Analysis," SAE Technical Paper 2011-01-2767, 2011, https://doi.org/10.4271/2011-01-2767.
- MSC NASTRAN Quick Reference Guide U.S.A. MSC.Software.Corporation
- A VARIABLE, FULLY FLEXIBLE DYNAMIC RESPONSE TOOL FOR SPECIAL INVESTIGATIONS (VARLOADS) Hofstee, J. Kier, T. Cerulli, C. Looye, G. Amsterdam : Proceedings International Forum on Aeroelasticity and Structural Dynamics 2003
- Development of Aircraft Flight Loads Analysis Models with Uncertainties for Pre-Design Studies Kier, T. Looye, G. Hofstee, J. Munich : International Forum on Aeroelasticity and Structural Dynamics 2005
- Process, Methods and Tools for Flexible Aircraft Flight Dynamics Model Integration Kier, T. Looye, G. Scharpenberg, M. Reijerkerk, M. Stockholm : International Forum on Aeroelasticity and Structural Dynamics 2007
- Harder, R.L. Desmarais, R.N. Interpolation Using Surface Splines 1972
- Moré, J. J. Garbow, B.S. Hillstrom, K.E. User guide for minpack-1 Argonne National Laboratory 1980 Technical Report ANL-80-74
- Waszak, M. R. Schmidt, D. K. Flight Dynamics of Aeroelastic Vehicles Journal of Aircraft 25 6 563 571 1988
- Waszak, M. R. Buttrill, C. S. Schmidt, D. K. Modeling and Model Simplification of Aeroelastic Vehicles: An Overview NASA 1992
- Canavin, J.R. Likins, P.W. Floating Reference Frames for Flexible Spacecraft Journal of Spacecraft and Rockets 14 1977 12 724 732
- Reschke, C. Integrated Flight Loads Modelling and Analysis for Flexible Transport Aircraft Universität Stuttgart Ph.D. thesis 2006
- Hedman, S. Vortex Lattice Method for Calculation of Quasi Steady State Loadings on Thin Elastic Wings Aeronautical Research Institute of Sweden 1965 Technical Report 105
- CORRECTION OF UNSTEADY AERODYNAMIC INFLUENCE COEFFICIENTS USING EXPERIMENTAL OR CFD DATA Bruns, J. M. Brink-Spalink, J. Madrid IFASD 2001 175 182
- Betrachtungen Über die gegenseitige Beeinflussung von Tragflügelsystemen Pistolesi, E. Gesammelte Vorträage der Hauptversammlung 1937 der Lilienthal Gesellschaft : Lilienthal Gesellschaft 1937
- UNIFYING MANOEUVRE AND GUST LOADS ANALYSIS MODELS Kier, T. M. Looye, G. H. N. Seattle : International Forum on Aeroelasticity and Structural Dynamics 2009
- Rodden, W.P. Albano, E. A doublet-lattice method for calculating lift distributions on oscillating surfaces in subsonic flows Journal of Aircraft 7 2 279 285 1969
- New developments and applications of the subsonic doublet-lattice method for nonplanar configurations Rodden, W.P. Giesing, J.P. Kalman, T.P. AGARD Symposium on unsteady aerodynamics for aeroelastic analyses of interfering surfaces 1971
- Airplane math modeling methods for active control design Roger, K. L. AGARD Structures and Materials Panel 1977 4-1 4-11
- Vepa, R. Finite State Modeling of Aeroelastic Systems NASA 1977
- Abel, I. An analytical technique for predicting the characteristics of a flexible wing equipped with an active flutter-suppression system and comparison with windtunnel data NASA 1979
- Berber, F. Internship Report Airbus 2010
- ESTIMATION OF GUSTS AND STRUCTURAL LOADS Henrichfreise, H. Bensch, L. Jusseit, J. Merz, L. Gojny, M. Seattle : s.n., 2009. International Forum on Aeroelasticity and Structural Dynamics (IFASD)
- Onboard, Real-Time Loads Monitoring Using The Loads Observer - Practical Implementation Aspects Augello, M. Bensch, L. Jusseit, J. Henrichfreise, H. International Forum on Aeroelasticity and Structural Dynamics (IFASD) 2009