Development of an Unsteady Aerodynamic Analysis Module for Rotor Comprehensive Analysis Code

Title & Authors
Development of an Unsteady Aerodynamic Analysis Module for Rotor Comprehensive Analysis Code
Lee, Joon-Bae; Yee, Kwan-Jung; Oh, Se-Jong; Kim, Do-Hyung;

Abstract
The inherent aeromechanical complexity of a rotor system necessitated the comprehensive analysis code for helicopter rotor system. In the present study, an aerodynamic analysis module has been developed as a part of rotorcraft comprehensive program. Aerodynamic analysis module is largely classified into airload calculation routine and inflow analysis routine. For airload calculation, quasi-steady analysis model is employed based on the blade element method with the correction of unsteady aerodynamic effects. In order to take unsteady effects - body motion effects and dynamic stall - into account, aerodynamic coefficients are corrected by considering Leishman-Beddoes's unsteady model. Various inflow models and vortex wake models are implemented in the aerodynamic module to consider wake induced inflow. Specifically, linear inflow, dynamic inflow, prescribed wake and free wake model are integrated into the present module. The aerodynamic characteristics of each method are compared and validated against available experimental data such as Elliot's induced inflow distribution and sectional normal force coefficients of AH-1G. In order to validate unsteady aerodynamic model, 2-D unsteady model for NACA0012 airfoil is validated against aerodynamic coefficients of McAlister's experimental data.
Keywords
Language
English
Cited by
1.
Aeroelastic Analysis of a Hingeless Rotor Using a Dynamic Wake Model, Journal of Aircraft, 2011, 48, 5, 1817
2.
The impact of yaw error on aeroelastic characteristics of a horizontal axis wind turbine blade, Renewable Energy, 2013, 60, 256
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