Dual-signal reconstruction algorithm under empirical mode decomposition in ultrasonic guided waves for temperature compensation

Abstract Pipeline structures are widely used in industry, but the increase in service life may lead to damage to the pipeline structure, bringing economic losses. Ultrasonic guided wave has been widely used for accurate damage detection of pipeline structures. However, temperature variations can also lead to changes in guided wave signals. In order to reduce the influence brought by the external environment, this paper proposes a dual-signal reconstruction method based on empirical mode decomposition. By simultaneously performing empirical mode decomposition on the baseline signal and the test signal and quantifying the correlation between their intrinsic mode functions, the similarity between the two signals can be effectively enhanced, thereby mitigating the impact of signal fluctuations caused by environmental variations. The experiments were conducted with 28.25 ∘ C as the baseline, and 100 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi mathvariant="normal">%</mml:mi> </mml:mrow> </mml:math> accuracy of condition monitoring was achieved under a temperature fluctuation of 9.5 ∘ C.