Non-Invasive Fast Detection of Internal Fouling Layers in Tubes and Ducts by Acoustic Vibration Analysis

The easy detection of fouling in duct systems is a persistent problem and remains a relevant demand for the chemical, oil, food, and pharmaceutical industries. The fouling process is the slow unwanted layer deposition of heavy organic and other dissolved solid materials out of transported fluids onto inner wall surfaces over an extended period of time. This work presents preliminary research results of vibrational hammer excitation for easy-to-use external non-invasive nondestructive fouling detection in pipelines and other large-scale duct systems. The main goal is the localization of inner pipe-layer formation and thickness estimation of the adsorbed material. Data were taken from the vibration variation in the presence of an inner pipe fouling layer using acoustic microphone detection. The experimental setup, achievable sensitivities, and limitations of the method are outlined.