Crack depth estimation by back scattering response
نویسنده
چکیده
Crack detection is one of the important tasks for industrial materials and products from the standpoint of safety. The assessment of the crack geometry would be a crucial parameter for quality control of products. The crack width and length could be rather easily identified by inspecting the actual surface picture. However, the depth of small crack would be difficult to estimate non-destructively. Therefore, it is useful to find the estimation method for the crack depth using electromagnetic wave. There are some studies to formulate the electromagnetic scattering by cracks [1]–[4]. Electromagnetic plane wave scattering by a narrow trough, which could serve as a canonical structure for crack model, has been analyzed rigorously in our previous investigation [4]. Based on our theoretical and numerical analysis [4] and [5], a simple estimation formula for the crack depth has been derived using dip frequency on the monostatic radar cross section (RCS) [6]. In order to check the validity of our crack depth estimation formula, some measurement results are obtained and shown in this paper. The estimation error is found to be less than 3 percent.
منابع مشابه
Crack Detection of Fixed-Simply Supported Euler Bernoulli Beam Using Elman Networks
In this paper, the crack detection and depth ratio estimation method are presented in beamlikestructures using Elman Networks. For this purpose, by using the frequencies of modes asinput, crack depth ratio of each element was detected as output. Performance of the proposedmethod was evaluated by using three numerical scenarios of crack for fixed-simply supportedbeam consisting of a single crack...
متن کاملModal Testing and Finite Element Analysis of Crack Effects on Turbine Blades
The study of vibration response of a turbine blade helps to detect the crack presence in the blade which alters its dynamic characteristics. The change is characterized by changes in the modal parameters associated with natural frequencies. In this paper, study of vibration response is made for turbine blade in the presence of a crack like defect. Turbine blade is initially assumed as a cantile...
متن کاملResonances and Crack Roughness Effects in Surface Breaking Cracks
This study deals with two different aspects of scattering from the cracks. The first one is the measurement of crack resonances by local probes and the second is the effect of the roughness of the crack forces on the scattering data. Unlike the scattering measurement reported elsewhere, these measurements of crack resonances are to be performed by local probes. Two different types of probes are...
متن کاملUltrasound diffusion for crack depth determination in concrete.
The determination of the depth of surface-breaking cracks in concrete specimens using an ultrasound diffusion technique is discussed. Experiments were carried out on precracked concrete specimens of varying crack depths (0%-40% of the specimen thickness). Contact transducers were placed at the specimen surface with source and receiver separated by the crack. Tone-burst excitations over a freque...
متن کاملEngineering of core/shell nanoparticles surface plasmon for increasing of light penetration depth in tissue (modeling and analysis)
Objectives: In this article, a new procedure for increasing the light penetration depth in a tissue is studied and simulated. It has been reported that the most important problem in biomedical optical imaging relates to the light penetration depth, and so this makes a dramatic restriction on its applications. In the optical imaging method, the detection of the backscattered pho...
متن کامل