The Calculation Of Unsteady Aerodynamics Effected By Gusts Upon An Airliner

When an aircraft is flying, the fight load it suffered containes maneuver load and gust load. As theairliner never does a maneuver, the gust load becomes the most important one which means that it isnecessary to verify the structure response generated by gust load to observe if the structure wasdestroyed or not. To investigate the structure response, first step is the calculation of aerodynamicforce. Vortex lattice method is the traditional way which has a quick computation speed, but theprecision is low and it can’t be used in the nonlinear problems. Recent years, the computer technologywas developed which leaded to the evolution of numerical simulation technology and theComputional Fluid Dynamics was born. The model used in CFD has a complete external shape whichmakes the result has a high-precision and a low cost.In this paper, CFD technology is used in the calculation of aerodynamic force generated by gusts.First, the gusts which were described by power spectral density of karman were translated fromfrequency domain to time domain. Second, the gusts were added to the flow field with the technologyof dynamic mesh in FLUENT software. Then naca0012and a three-dimensional wing was used in thetesting of algorithm. At last, the method was used in the simulation of unsteady aerodynamics effectedby gusts on a civil aircraft, under the condition of normal flight, aileron deflection and spoiler opening.The method has a high precision and good computational efficiency, which will have a widespreaduse in the future.This project is supported by Program for ChangJiang Scholars and Innovative Research Team inUniversity (PCSIRT)(NO.IRT0968), the National Natural Science Foundation of China(NO.50830201) and the cooperation program with COMAC.