Simulation Of Ultrasonic Wave Propagation Research Articles

Evaluation of ultrasonic cleaning process

Purpose. To establish relationship between intensity of ultrasonic cleaning and an ultrasonic response fixed at a set point. To determine the influence of liquid contamination on this signal. To specify parameters of an ultrasonic signal to evaluate the course of cleaning a preset section of a body. To define limiting values indicating efficiency of ceasing the cleaning process. Methodology. The research is based on simulation of ultrasonic wave propagation in the heterogeneous environment and subsequent analysis of the signals by using software. Findings. Dependences are established to form evaluation of the course of the cleaning process by parameters of the ultrasonic response. It is found that both the bodys state and that of the liquid affect the ultrasonic response obtained by the sensor at the set point during ultrasonic cleaning. With high contamination (>30%) the state of the liquid becomes a critical factor for forming the signal of the ultrasonic response. With that, there is an abrupt reduction of threshold signal arrival time and increase in the main amplitude, which is to be one of indicators of ceasing the cleaning process in case of its inefficiency. With lower contamination, suspended contaminant particles only correct the signal to some extent without distorting it. There is a relationship between reduction of contamination, the arrival time of threshold signal, on the one hand, and the value of the main amplitude and the 2nd and 3rd-order nonlinearity coefficients, on the other hand. The arrival of the threshold value of the signal is the major parameter determining intensity of cleaning, i.e. reduction of contaminant thickness, which is determined by the value of the main amplitude of the signal and the 2nd and 3rd-order nonlinearity coefficients. Originality. For the first time, methods for evaluating the course of the ultrasonic cleaning process by analyzing ultrasonic responses at a specified point have been developed. Practical value. To consider spatial distribution of the ultrasonic cleaning process, its control is to be based on evaluating the bodys contamination in several preset points. To implement this, the character of dependences between changes in contamination of the body section and parameters of the fixed ultrasonic response is determined. Impacts are considered of suspended contaminant particles in the liquid on the signal analyzed. The observed relationship will provide the basis for building the spatially distributed control over ultrasonic cleaning considering the cleaned bodys state.

Modeling concept and numerical simulation of ultrasonic wave propagation in a moving fluid-structure domain based on a monolithic approach

• New multiphysics model for structural health monitoring (SHM) systems for alternative material specifications. • The problem of ultrasonic guided waves (UGWs) propagation in fluidstructure interface features the NDT principle. • Modeling the UGWs propagation with/without the fluid-structure interaction (FSI) problem in the ALE framework. • The double-loop linear solving technique applied for the time-dependent coupled models using monolithic approach. • Numerical simulations of multiphysics problems, contrasted against the approximate experimental data. In the present study, we propose a novel multiphysics model that merges two time-dependent problems – the Fluid-Structure Interaction (FSI) and the ultrasonic wave propagation in a fluid-structure domain with a one directional coupling from the FSI problem to the ultrasonic wave propagation problem. This model is referred to as the “eXtended fluid-structure interaction (eXFSI)” problem. This model comprises isothermal , incompressible Navier–Stokes equations with nonlinear elastodynamics using the Saint-Venant Kirchhoff solid model. The ultrasonic wave propagation problem comprises monolithically coupled acoustic and elastic wave equations. To ensure that the fluid and structure domains are conforming, we use the ALE technique. The solution principle for the coupled problem is to first solve the FSI problem and then to solve the wave propagation problem. Accordingly, the boundary conditions for the wave propagation problem are automatically adopted from the FSI problem at each time step. The overall problem is highly nonlinear, which is tackled via a Newton-like method. The model is verified using several alternative domain configurations . To ensure the credibility of the modeling approach, the numerical solution is contrasted against experimental data.

2-D simulation of ultrasonic wave propagation in solid propellant using finite element method

2-D simulation of ultrasonic wave propagation in solid propellant using finite element method

A fluid model for the simulation of fluid‐structure interaction in the Scaled Boundary Finite Element Method for prismatic structures

AbstractThe Scaled Boundary Finite Element Method is known as an efficient method for the simulation of ultrasonic wave propagation. As to investigate acoustic wave behavior in case of fluid‐structure interaction, a fluid model is implemented in the SBFEM for prismatic structures. To omit coupling terms a displacement‐based formulation is used. Spurious modes, which occur in the solution, are suppressed using a penalty parameter. To verify this formulation dispersion curves obtained with Comsol Multiphysics are compared to results of SBFEM. The results of both methods are in very good agreement.

Simulations of ultrasonic wave propagation in concrete based on a two-dimensional numerical model validated analytically and experimentally

Several non-destructive evaluation techniques to characterize concrete structures are based on ultrasonic wave propagation. The interpretation of the results is often limited by the scattering phenomena between the ultrasonic wave and the high concentration aggregates contained in the cement matrix. Numerical simulations allow for further insights. This study aims to build a two-dimensional numerical model in order to reproduce and interpret ultrasonic wave propagations in concrete. The model is built in a spectral-element software package called SPECFEM2D. The validation of the numerical tool is based on the use of resin samples containing different amount of aluminum rods from low (5%) to high concentration (40%), the last one being representative of aggregate concentration in concrete. These samples are characterized using an ultrasonic testing bench (ultrasonic water tank) from 150 kHz to 370 kHz. The measured results are analyzed in terms of phase velocity and attenuation which are the main parameters of coherent waves. As homogenization models such as the Waterman-Truell or Conoir-Norris models are usually used to model coherent waves in two-phase systems, we also compare the experimental and numerical results against them. We confirm that the use of these homogenization models is limited to low concentration of scattering phase, which is not adapted to applications to concrete. Finally, we use our numerical tool to carry out a parametric study on scatterer concentration, shape, orientation and size distribution of aggregates in concrete. We show that aggregate orientation has an influence on coherent wave parameters, but aggregate shape has not.

Study on three-dimensional simulation of ultrasonic wave propagation in statically cast stainless steel using numerical solidified microstructure model

Study on three-dimensional simulation of ultrasonic wave propagation in statically cast stainless steel using numerical solidified microstructure model

Study of the ultrasonic propagation law in the gas–liquid two-phase flow of deepwater riser through numerical simulation

In the drilling of deepwater wells, early detection of gas kicks is a crucial and difficult well-control task. A common and advantageous method is the underwater ultrasonic monitoring of the gas–liquid two-phase flow of deepwater risers. This study focuses on the problems of the early-stage ultrasonic monitoring of gas kicks in deepwater risers, and combines theoretical analysis and experimental verification to establish a method for finite element numerical simulation of ultrasonic wave propagation in the gas–liquid two-phase flow of a deepwater riser annulus. The acoustic-solid coupling module of COMSOL Multiphysics software was adopted. Through pattern analysis of ultrasonic wave propagation under different conditions, the sensitivity analysis was carried out by combining time domain and frequency domain analysis. Through analysis, two characteristic parameters of ultrasonic signals sensitive to the gas–liquid ratio, namely, the amplitude standard deviation (S) and frequency domain mean (μ) were selected. Their degrees of sensitivity to gas bubble size and density were analyzed to determine the optimal installation location of an ultrasonic receiver probe. And the optimal installation locations were located at 66°–88° and −66°−−88° of the arc area. Finally, a quantitative relationship between the ultrasonic signal characteristic parameters (S and μ) and the void fractions of risers (β) was established by using two-factor regression analysis. It was proved that its relative error was 4.5%, which was less than the acceptable error threshold of 5%, thus meeting the engineering requirements.

イメージベースモデリングによる超音波伝搬シミュレーション( 音響分野で活用される時間領域有限差分(FDTD)法)

イメージベースモデリングによる超音波伝搬シミュレーション( 音響分野で活用される時間領域有限差分(FDTD)法)

Three dimensional image-based simulation of ultrasonic wave propagation in polycrystalline metal using phase-field modeling

When modeling ultrasonic wave propagation in metals, it is important to introduce mesoscopic crystalline structures because the anisotropy of the crystal structure and the heterogeneity of grains disturb ultrasonic waves. In this paper, a three-dimensional (3D) polycrystalline structure generated by multiphase-field modeling was introduced to ultrasonic simulation for nondestructive testing. 3D finite-element simulations of ultrasonic waves were validated and compared with visualization results obtained from laser Doppler vibrometer measurements. The simulation results and measurements showed good agreement with respect to the velocity and front shape of the pressure wave, as well as multiple scattering due to grains. This paper discussed the applicability of a transversely isotropic approach to ultrasonic wave propagation in a polycrystalline metal with columnar structures.

FDTD simulations of ultrasonic wave propagation in the cortical bone with heterogeneity

The ultrasonic axial transmission (AT) technique is known to assess the cortical bone of femur and tibia. After the first application of the finite difference time domain (FDTD) method [1], the wave propagation in bone has been discussed by both simulation and experimental studies. The wave propagation depends on the wave velocity, bone geometry (curvature, cortical thickness), anisotropy, heterogeneity, etc. In this study, we have investigated the ultrasonic wave propagation in the cortical bone with heterogeneity (stiffness distribution) by FDTD method. Using the stiffness distribution of bovine cortical bone, experimentally measured by Yamato and Nakatsuji [2], [3], wave propagation of one cycle of sinusoidal wave at 0.5~1 MHz was investigated, assuming cuboid samples. The wave velocities inside the bone were higher than those of the bone surfaces. The complex propagating waves were slightly concentrated at the bone surface. The results indicate that the stiffness distribution is also an important factor to understand the wave propagation. [1] E. Bossy et al., J. Acoust. Soc. Am. 115 , 2314 (2004). [2] Y. Yamato et al., Jpn. J. Appl. Phys. 47, 4096 (2008). [3] T. Nakatsuji et al., Jpn. J. Appl. Phys. 50, 07HF18 (2011).

Finite element simulation of ultrasonic wave propagation in a dental implant for biomechanical stability assessment.

Dental implant stability, which is an important parameter for the surgical outcome, can now be assessed using quantitative ultrasound. However, the acoustical propagation in dental implants remains poorly understood. The objective of this numerical study was to understand the propagation phenomena of ultrasonic waves in cylindrically shaped prototype dental implants and to investigate the sensitivity of the ultrasonic response to the surrounding bone quantity and quality. The 10-MHz ultrasonic response of the implant was calculated using an axisymetric 3D finite element model, which was validated by comparison with results obtained experimentally and using a 2D finite difference numerical model. The results show that the implant ultrasonic response changes significantly when a liquid layer is located at the implant interface compared to the case of an interface fully bounded with bone tissue. A dedicated model based on experimental measurements was developed in order to account for the evolution of the bone biomechanical properties at the implant interface. The effect of a gradient of material properties on the implant ultrasonic response is determined. Based on the reproducibility of the measurement, the results indicate that the device should be sensitive to the effects of a healing duration of less than one week. In all cases, the amplitude of the implant response is shown to decrease when the dental implant primary and secondary stability increase, which is consistent with the experimental results. This study paves the way for the development of a quantitative ultrasound method to evaluate dental implant stability.

Simulation of ultrasonic wave propagation in welds using ray-based methods

Austenitic or bimetallic welds are particularly difficult to control due to their anisotropic and inhomogeneous properties. In this paper, we present a ray-based method to simulate the propagation of ultrasonic waves in such structures, taking into account their internal properties. This method is applied on a smooth representation of the orientation of the grain in the weld. The propagation model consists in solving the eikonal and transport equations in an inhomogeneous anisotropic medium. Simulation results are presented and compared to finite elements for a distribution of grain orientation expressed in a closed-form.

Modeling of piezo-induced ultrasonic wave propagation in composite structures using layered solid spectral element

This article presents the development of a three-dimensional spectral element-based Piezo-Enabled Spectral Element Analysis code to simulate piezo-induced ultrasonic wave propagation in composite structures. Piezo-Enabled Spectral Element Analysis solves the coupled electromechanical governing equations for a given arbitrary voltage input to a piezoelectric actuator and outputs the voltage response of the piezoelectric sensors. In case of modeling laminated composites, one element per ply is computationally expensive, and smeared material properties may give inaccurate results; hence, a layered solid spectral element is introduced. Layered solid spectral element can model several plies per element and uses combined nodal quadrature and Simpson’s 1/3 integration rule for numerical integration of mechanical stiffness matrix. It is worth noting that Piezo-Enabled Spectral Element Analysis can interface with commercial finite element mesh generators such as Abaqus/CAE to model structures with complex configuration. Delaminations and debonds are modeled by separating the nodes in the damaged area to create a volume split. Experiments and simulations have been carried out to verify and validate Piezo-Enabled Spectral Element Analysis for composites. This article also presents simulations of ultrasonic wave propagation in a stiffened composite plate with delamination and debond.

Numerical simulation of ultrasonic wave propagation for the evaluation of dental implant biomechanical stability

Osseointegration of dental implants remains poorly understood. The objective of this numerical study is to understand the propagation phenomena of ultrasonic waves in prototypes cylindrically shaped implants and to investigate the sensitivity of their ultrasonic response to the surrounding bone biomechanical properties. The 10 MHz ultrasonic response of the implant was calculated using a finite difference numerical simulation tool and was compared to rf signals taken from a recent experimental study by Mathieu et al. [Ultrasound Med. Biol. 37, 262-270 (2011a)]. Reflection and mode conversion phenomena were analyzed to understand the origin of the different echoes and the importance of lateral wave propagation was evidenced. The sensitivity of the ultrasonic response of the implant to changes of (i) amount of bone in contact with the implant, (ii) cortical bone thickness, and (iii) surrounding bone material properties, was compared to the reproducibility of the measurements. The results show that, either a change of 1 mm of bone in contact with the implant, or 1.1 mm of cortical thickness or 12% of trabecular bone mass density should be detectable. This study paves the way for the investigation of the use of quantitative ultrasound techniques for the evaluation of bone-implant interface properties and implant stability.

Nondestructive evaluation of defects in concrete structures based on finite element simulations of ultrasonic wave propagation

Concrete structures require periodic inspections and quality control to assess their structural integrity. For this task, several methodologies based on the use of different technologies have been previously proposed. In particular, nondestructive evaluations, based on the use of ultrasonic wave propagation, have proved to be attractive due to the possibility to perform reliable assessments of concrete structures. In this paper, an approach exploiting ultrasonic propagation characteristics is proposed. This approach is developed by using data obtained from numerical simulations, whereas proper simulation settings to perform the diagnosis are obtained by preliminary studies. Subsequently, an automatic inspection method to determine the position of defects is developed. The aim of the method consists of determining the position of a defect by the computation of flight times related to signals reflected by anomalies in the structure. Such computation is based on a preliminary classification of defect positions that combines a genetic algorithm for a feature selection and a statistical approach for classification. The performances of the proposed method are evaluated in a specific study case, showing satisfactory numerical results, which show that this approach can be used to identify the position of defects.

Simulation of ultrasonic wave propagation in anisotropic cancellous bone immersed in fluid

Cancellous bone at the macroscopic level is known as being a two-phase anisotropic material composed of a solid rod-like or plate-like skeleton filled with viscous fluid. Quantifying the mechanical properties of cancellous bones by using ultrasound techniques should take into account these complexities. This paper proposes a model to investigate the transient ultrasonic wave propagation in a cancellous bone immersed in an acoustic fluid. A finite element time-domain model based on u s - w formulation is developed to consider an anisotropic porous medium (Biot’s model) coupled with two acoustic fluids. Some numerical results are shown to illustrate the influence of the bone anisotropy to the reflection and transmission of plane waves in a human cancellous bone specimen.

Feasibility study of wide-band low-profile ultrasonic sensor with flexible piezoelectric paint

This paper presents a feasibility study of flexible piezoelectric paint for use in wide-band low-profile surface-mount or embeddable ultrasonic sensor for in situ structural health monitoring. Piezoelectric paint is a piezoelectric composite with 0-3 connectivity. Because of its ease of application, piezoelectric paint can be readily fabricated into sensing element with complex pattern. This study examines the characteristics of piezoelectric paint in acoustic emission signal and ultrasonic guided wave sensing. A series of ultrasonic tests including pitch catch and pencil break tests were performed to validate the ultrasonic wave sensing capability of piezoelectric paint. The results of finite element simulation of ultrasonic wave propagation, and acoustic emission generated by a pencil lead break on an aluminum plate are also presented in this paper along with corresponding experimental data. Based on the preliminary experimental results, the piezoelectric paint appears to offer a promising sensing material for use in real-time monitoring of crack initiation and propagation in both metallic and composite structures.

3-D finite element simulation for ultrasonic propagation in tooth

Objectives Ultrasonic testing of the tooth has been suggested as an alternative method of identifying dental pathology. Due to the complex geometry and low transmission efficiency of ultrasonic signals in tooth structures, it is difficult to establish one-to-one correspondence between ultrasonic behaviour and specific tooth pathologies both in vitro and in vivo. In order to facilitate ultrasonic diagnosis in dental applications, finite element modeling (FEM) was used to simulate ultrasonic wave propagation in teeth with several dental conditions. Methods 3-D finite element tooth models were developed. The geometry of the tooth models was defined by 3-D images generated by scanning real tooth samples using an X-ray computerized tomography machine. Poro-elastic material was used to simulate the mechanical behaviour of the dentine. Numerical simulations of ultrasonic wave propagation were performed on the 3-D FEM models altered to mimic various dental conditions. The software ABAQUS was used as the calculator in the simulation. Results Excellent replication of ultrasonic behaviours by the FEM simulation was demonstrated through comparison of the simulation results with those of the actual ultrasonic testing on tooth specimens. Pathologies, such as caries, were also simulated on the finite element models. The unique influence of each dental condition on the patterns of ultrasonic waves propagating through the tooth (A-scan) was observed. Conclusions Through FEM simulation, the influence of a particular dental pathology on ultrasonic wave pattern can be studied without the impact of other parameters. This will lead to a better understanding of how ultrasound could be applied to the diagnosis of pathology within teeth.

Ultrasonic Propagation Through Trabecular Bone Modeled as a Random Medium

A method based on Gaussian random fields was used to generate three media having identical first and second order properties as three original trabecular bone specimens. Attenuation coefficients in both sets of specimens were computed after numerical simulations of ultrasonic wave propagation, using a finite difference time domain (FDTD) code without absorption. In generated media, they exhibited a linear trend for frequency dependence and their values were close to those obtained in the original specimens. These results suggest that combining a simplified description of trabecular bone micro-architecture with a multi-order scattering model could be relevant to predict attenuation due to scattering in trabecular bone.

A Large Scale Simulation of Ultrasonic Wave Propagation in Concrete Using Parallelized EFIT

A time domain simulation tool for the ultrasonic propagation in concrete is developed using the elastodynamic finite integration technique (EFIT) and the image-based modeling. The EFIT is a grid-based time domain differential technique and easily treats the different boundary conditions in the inhomogeneous material such as concrete. Here, the geometry of concrete is determined by a scanned image of concrete and the processed color bitmap image is fed into the EFIT. Although the ultrasonic wave simulation in such a complex material requires much time to calculate, we here execute the EFIT by a parallel computing technique using a shared memory computer system. In this study, formulations of the EFIT and treatment of the different boundary conditions are briefly described and examples of shear horizontal wave propagations in reinforced concrete are demonstrated. The methodology and performance of parallelization for the EFIT are also discussed.