Design of FOD Easy Fracturing Rod Based on Finite Element Analysis and Fracture Criterion

The structural design of the easy fracturing rod for the detection system of foreign object debris (FOD) of airport runway is the key to ensure the effective work of the detection system and plays a crucial role in preventing airport security risks caused by FOD. In this paper, the easy fracturing rod of FOD detection system is taken as the research object. The design of semicircular notch in circular tube is proposed to realize the comprehensive mechanical properties of the easy fracturing rod, including easy fracturing and enough fatigue resistance. The stress and strain states of easy fracturing rod with different fillet radius, pipe wall thickness and notch shape under different working loads are analyzed by finite element simulation. The results show that as the fillet radius increases and the wall thickness decreases, the stress level at the notch root increases, which can make the easy fracturing rod break rapidly when it is hit by FOD, so the rod has the characteristics of easy fracturing, but it will reduce the fatigue life. On the contrary, the fatigue life will be improved while it is not easy to meet the easy fracturing characteristics. Reasonable adjustment of wall thickness and fillet radius can make the easy fracturing rod have the comprehensive mechanical properties of easy fracturing and enough fatigue resistance.