CAJ | 학술논문

为了研究考虑地面干扰的飞行器非定常气动特性，基于滑移网格技术，通过求解二维非定常Euler方程，对不同近地高度下的NACA0012翼型的动态振动特性进行了数值模拟。分析了存在地面干扰时的升力系数以及俯仰力矩系数迟滞环变化，并结合强迫振动法，计算了翼型各个近地高度下的纵向组合动导数。结果表明，地面效应不仅对定常流场产生影响，更显著地影响了非定常气动力及力矩，近地高度越小，这种效应越明显，使得升力系数的迟滞环面积变小，幅值减小，而俯仰力矩系数的迟滞环变化不规律，力矩系数的动导数随着近地高度减小而增大（绝对值减小），纵向的动态稳定性产生损失。地面效应干扰在飞行器非定常气动研究中应该引起重视。
위료연구고필지면간우적비행기비정상기동특성，기우활이망격기술，통과구해이유비정상Euler방정，대불동근지고도하적NACA0012익형적동태진동특성진행료수치모의。분석료존재지면간우시적승력계수이급부앙력구계수지체배변화，병결합강박진동법，계산료익형각개근지고도하적종향조합동도수。결과표명，지면효응불부대정상류장산생영향，경현저지영향료비정상기동력급력구，근지고도월소，저충효응월명현，사득승력계수적지체배면적변소，폭치감소，이부앙력구계수적지체배변화불규률，력구계수적동도수수착근지고도감소이증대（절대치감소），종향적동태은정성산생손실。지면효응간우재비행기비정상기동연구중응해인기중시。
To simulate the unsteady flow around an oscillating NACA 0012 airfoil with ground effect , the Euler equations are solved and sliding mesh is used ,then the dynamic characteristics are investigated nu-merically at different heights between airfoil and ground , and the change of lift and moment hysteresis loops are analyzed ,finally combined with small amplitude oscillation method ,all the dynamic derivatives at different heights are calculated .The result show that ground effect has influence on both steady and un-steady flow fields ,the lift hysteresis loop changes smaller as the height lower ,while the moment dynamic derivative become bigger ,which means making loss on longitudinal dynamic stability .The ground effect should be considered during unsteady aerodynamic research .