大型机翼整体壁板喷丸延展量数值模拟

Numerical simulation on elongation of large integral wing panel after shot peening

分析了大型机翼整体壁板在喷丸成形及强化过程中产生延展变形的机理,并介绍了几种喷丸成形数值模拟的方法;对于弹丸不重叠排布的情况,采用长方形和三角形两种喷丸覆盖率计算模型,对于弹丸随机排布发生重叠的情况下,采用Avrami覆盖率计算模型,通过多弹丸撞击长方体胞元的有限元模拟方法,得到弹丸撞击后靶材的表层诱导应力场的分布规律;进而采用直接应力法建立了预测喷丸成形及强化延展变形的有限元模拟方法,通过试板喷丸成形参数和试板弯曲及延展的变形规律的试验,验证了其有效性,进而将其应用于C919机翼下前整体壁板板坯延展量的模拟,取得了与试验吻合较好的结果。

The elongation mechanism of large integral wing panel in the process of shot peening forming and shot peen strengthening was analyzed,and several common numerical simulation methods of shot peen forming were also introduced. Rectangle and triangle coverage ratio calculation models were adopted with non overlapping arrangement of peen. The Avrami coverage ratio calculation model was adopted with overlapping arrangement of peen. After the peen impacted the plate,the induced stress distribution on its surface was obtained by the numerical method of multi-shot impacting cuboid cell. Furthermore,the elongation of plate after peen forming and shot peen strengthening was simulated by directional stress method. The validity of the above methods were verified by the experiments of shot peening parameters and curvature of plates,as well as the elongation deformation. Therefore,an ideal result in accordance with the experiment was obtained by applying the numerical simulation method to calculate the elongation of C919 front bottom integral wing panel.