管道组合缺陷漏磁检测信号干扰特性的数值模拟研究OA

To address the significant mutual interference of magnetic flux leakage(MFL)signals under combined defect conditions in pipelines and the difficulty in uniformly determining the adjacent interference distance,a numerical MFL detection models for internal combined defects in pipelines were established using the finite element method with two typical spatial configurations:horizontal alignments and circumferential alignments.A peak attenuation rate based on signal-to-noise ratio characteristics was introduced as a quantitative criterion to systematically analyze the interference characteristics of MFL signals under different defect arrangements and geometric parameters.The results indicate that combined defects in horizontal alignment exhibit peak attenuation type interference,whereas those in circumferential alignment present a distinct peak enhancement superposition characteristic.Under typical defect dimensions,the adjacent interference distance for circumferential alignment is significantly larger than that for horizontal alignment.Moreover,the adjacent interference distance corresponding to the radial component is consistently larger than that of the axial component.For horizontal alignment,the maximum interference distance is approximately 5 times the defect axial length.As the defect depth increases from 1 mm to 4 mm,the adjacent interference distance monotonically increases from 28 mm to 47 mm.For circumferential alignment,the interference distance exhibits a non-monotonic variation,initially increasing and then decreasing as the the increases of defect axial length.As the defect depth increases,the adjacent interference distance monotonically increases from 47 mm to 100 mm.The research results can provide quantitative basis for the decoupling analysis of MFL signals and the layout optimization of detector probe under combined defect conditions.