41st Aerospace Sciences Meeting and Exhibit · 2003 · 85 citations · 7 references
EngineeringAerospace EngineeringMechanical EngineeringAerodynamicsFlight MechanicsPropulsionAerodynamic DesignAerodynamic TestingExperimental AerodynamicsWind-tunnel TestingAerodynamic Force GenerationAerodynamic Force ModelingAerodynamic ModelingAerodynamic Moment ModelingAircraft Aerodynamics TestingMoment CoefficientOrthogonal BlockingWind Tunnel Modeling
The study describes a wind tunnel experiment to characterize aerodynamic and propulsion forces and moments on a research model airplane. The 7‑ft FASER model, equipped with a tractor propeller, was tested in NASA Langley’s 12‑ft low‑speed wind tunnel using traditional sweeps and modern experimental design with power level as an independent variable, and the data were modeled with multivariate orthogonal functions and efficient generation, expansion, and blocking techniques to produce accurate analytic models. The resulting models provide smooth, differentiable polynomial functions of non‑dimensional aerodynamic force and moment coefficients, suitable for nonlinear aircraft simulation.
A wind tunnel experiment for characterizing the aerodynamic and propulsion forces and moments acting on a research model airplane is described. The model airplane called the Free-flying Airplane for Sub-scale Experimental Research (FASER), is a modified off-the-shelf radio-controlled model airplane, with 7 ft wingspan, a tractor propeller driven by an electric motor, and aerobatic capability. FASER was tested in the NASA Langley 12-foot Low-Speed Wind Tunnel, using a combination of traditional sweeps and modern experiment design. Power level was included as an independent variable in the wind tunnel test, to allow characterization of power effects on aerodynamic forces and moments. A modeling technique that employs multivariate orthogonal functions was used to develop accurate analytic models for the aerodynamic and propulsion force and moment coefficient dependencies from the wind tunnel data. Efficient methods for generating orthogonal modeling functions, expanding the orthogonal modeling functions in terms of ordinary polynomial functions, and analytical orthogonal blocking were developed and discussed. The resulting models comprise a set of smooth, differentiable functions for the non-dimensional aerodynamic force and moment coefficients in terms of ordinary polynomials in the independent variables, suitable for nonlinear aircraft simulation.
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