Nonlinear Ultrasound Crack Detection with Multi-Frequency Excitation—A Comparison

Frank Mevissen

Research output: Contribution to journalArticlepeer-review

2 Citations (SciVal)


Nonlinear ultrasound crack detection methods are used as modern, non-destructive testing tools for inspecting early damages in various materials. Nonlinear ultrasonic wave modulation, where typically two or more frequencies are excited, was demonstrated to be a robust method for failure indicators when using measured harmonics and modulated response frequencies. The aim of this study is to address the capability of multi-frequency wave excitation, where more than two excitation frequencies are used, for better damage identification when compared to single and double excitation frequencies without the calculation of dispersion curves. The excitation frequencies were chosen in such a way that harmonic and modulated response frequencies meet at a specific frequency to amplify signal energy. A new concept of nonlinearity parameter grouping with multi-frequency excitation was developed as an early failure parameter. An analytical solution of the one-dimensional wave equation was derived with four fundamental frequencies, and a total of 64 individual and 30 group nonlinearity parameters. Experimental validation of the approach was conducted on metal plates with different types of cracks and on turbine blades where cracks originated under service conditions. The results showed that the use of multi-frequency excitation offers advantages in detecting cracks.
Original languageEnglish
Article number5368
Pages (from-to)5368
Number of pages27
Issue number16
Publication statusPublished - 9 Aug 2021


  • Crack detection
  • Gas turbines
  • Modulation
  • Nonlinear ultrasound

ASJC Scopus subject areas

  • Analytical Chemistry
  • Information Systems
  • Instrumentation
  • Atomic and Molecular Physics, and Optics
  • Electrical and Electronic Engineering
  • Biochemistry


Dive into the research topics of 'Nonlinear Ultrasound Crack Detection with Multi-Frequency Excitation—A Comparison'. Together they form a unique fingerprint.

Cite this