scholarly journals Coalescence Dynamics of Acoustically Levitated Droplets

Micromachines ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 343 ◽  
Author(s):  
Koji Hasegawa ◽  
Ayumu Watanabe ◽  
Akiko Kaneko ◽  
Yutaka Abe
Keyword(s):  
Sound Pressure ◽  
Phased Array ◽  
Phased Arrays ◽  
Industrial Applications ◽  
Acoustic Levitation ◽  
Droplet Dynamics ◽  
Levitated Droplets ◽  
Ultrasonic Phased Array ◽  
Velocity Information ◽  
The Impact

The contactless coalescence of a droplet is of paramount importance for physical and industrial applications. This paper describes a coalescence method to be used mid-air via acoustic levitation using an ultrasonic phased array system. Acoustic levitation using ultrasonic phased arrays provides promising lab-on-a-drop applications, such as transportation, coalescence, mixing, separation, evaporation, and extraction in a continuous operation. The mechanism of droplet coalescence in mid-air may be better understood by experimentally and numerically exploring the droplet dynamics immediately before the coalescence. In this study, water droplets were experimentally levitated, transported, and coalesced by controlled acoustic fields. We observed that the edges of droplets deformed and attracted each other immediately before the coalescence. Through image processing, the radii of curvature of the droplets were quantified and the pressure difference between the inside and outside a droplet was simulated to obtain the pressure and velocity information on the droplet’s surface. The results revealed that the sound pressure acting on the droplet clearly decreased before the impact of the droplets. This pressure on the droplets was quantitatively analyzed from the experimental data. Our experimental and numerical results provide deeper physical insights into contactless droplet manipulation for futuristic lab-on-a-drop applications.

scholarly journals Coalescence Dynamics of Acoustically Levitated Droplets

2020 ◽  
Author(s):  
Koji Hasegawa ◽  
Ayumu Watanabe ◽  
Akiko Kaneko ◽  
Yutaka Abe
Keyword(s):  
Sound Pressure ◽  
Phased Arrays ◽  
Industrial Applications ◽  
Droplet Surface ◽  
Acoustic Levitation ◽  
Droplet Dynamics ◽  
Levitated Droplets ◽  
Ultrasonic Phased Array ◽  
Velocity Information ◽  
The Impact

The contactless coalescence of a droplet is of paramount importance for physical and industrial applications. This paper describes a coalescence method in mid-air via acoustic levitation using an ultrasonic phased array system. Acoustic levitation using ultrasonic phased arrays provides promising lab-on-a-drop applications, such as transportation, coalescence, mixing, separation, evaporation, and extraction in a continuous operation. The mechanism of droplet coalescence in mid-air may be better understood by experimentally and numerically exploring the droplet dynamics immediately before the coalescence. In this study, water droplets were experimentally levitated, transported, and coalesced by controlling acoustic fields. We observed that the edge of droplets deformed and attracted each other immediately before the coalescence. Through image processing, the radii of curvature of the droplets were quantified and the pressure difference between the inside and outside the droplet was simulated to obtain the pressure and velocity information on the droplet surface. The results revealed that the sound pressure acting on the droplet clearly decreased before the impact of the droplets. This pressure on the droplets was quantitatively analyzed from the experimental data. Our experimental and numerical results provide deeper physical insights into contactless droplet manipulation for futuristic lab-on-a-drop applications.

scholarly journals Acoustic Manipulation of Droplets under Reduced Gravity

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Koji Hasegawa ◽  
Ayumu Watanabe ◽  
Yutaka Abe
Keyword(s):  
Phased Arrays ◽  
Reduced Gravity ◽  
Fundamental Physics ◽  
Droplet Dynamics ◽  
Half Wavelength ◽  
Future Space ◽  
Levitated Droplet ◽  
Ultrasonic Phased Array ◽  
Nonlinear Acoustic ◽  
Physical Phenomena

Abstract Contactless manipulation of matter is essential for studying physical phenomena. Acoustic manipulation of liquid samples using ultrasonic phased arrays provides a novel and attractive solution for mid-air manipulation, such as levitation, transportation, coalescence, mixing, separation, evaporation, and extraction, with a simple and single sequence. Despite the importance of gravity in droplet dynamics, its effect on a levitated droplet with an ultrasonic phased array remains unclear. To disseminate acoustic manipulation, better understanding of the fundamental physics of a droplet manipulated by ultrasonic phased arrays is required. Here, we show contactless levitation, transportation, and coalescence of multiple droplets under both ground and reduced gravity. Under ground gravity, the possible levitation size of the sample is limited to below the half wavelength of sound. Under reduced gravity, however, droplets that are larger than the limit can be successfully levitated, transported, and coalesced. Furthermore, the threshold of sound pressure for droplet levitation and manipulation could be minimised with the suppression of nonlinear acoustic phenomena under reduced gravity. These insights promote the development of contactless manipulation techniques of droplets for future space experiment and inhabitancy.

A Case Study of the Crack Sizing Performance of the Ultrasonic Phased Array Combined Crack and Wall Loss Inspection Tool on the Centennial Pipeline, the Defect Evaluation, Including the Defect Evaluation, Field Feature Verification and Tool Performance Validation (Performed by Marathon Oil, DNV and GE Oil & Gas)

2010 ◽  
Author(s):  
T. Hrncir ◽  
S. Turner ◽  
S. J. Polasik ◽  
P. Vieth ◽  
D. Allen ◽  
...  
Keyword(s):  
Phased Array ◽  
Subject Line ◽  
Tool Performance ◽  
Ultrasonic Phased Array ◽  
Survey Results ◽  
Wall Loss ◽  
Products Pipeline ◽  
Performance Validation ◽  
The Impact

GE performed an ultrasonic phased-array (USCD DUO) in-line inspection (ILI) survey of a 24-inch and 26-inch products pipeline. The primary purpose of this ILI survey was to detect and characterize stress corrosion cracking (SCC). A dig verification was subsequently performed throughout 2008 in order to establish a higher level of confidence in the detection and depth-sizing capabilities of this technology. Presented herein is an overview of the USCD technology and experience, the method used for validating the ILI survey results, enhancements to the ILI data analysis, and the impact on managing the integrity of the subject line section.

scholarly journals Pipeline Girth Weld Inspections Using Ultrasonic Phased Arrays

2003 ◽  
Author(s):  
Michael Moles ◽  
Noe¨l Dube´ ◽  
Ed Ginzel
Keyword(s):  
Phased Array ◽  
Phased Arrays ◽  
Gas Pipeline ◽  
Safety Hazard ◽  
Lack Of Fusion ◽  
Track Record ◽  
Ultrasonic Phased Array

Automated ultrasonics is rapidly replacing radiography worldwide for gas pipeline girth weld inspections. Compared with radiography, mechanized ultrasonics is more reliable, faster, has better detection of critical Lack of Fusion defects, and poses no safety hazard. Phased arrays are the latest development in AUT, and present major improvements over conventional ultrasonics. Probe pans are lighter and smaller; scans are quicker due to the smaller probe pan; phased arrays are considerably more flexible for changes in pipe dimensions or weld profiles, and for different scan patterns for unusual defects; special scans can be made for specific problems. This paper describes the PipeWIZARD ultrasonic phased array system for girth weld inspections, based on the ASTM E-1961 code and compatible with API 1104 19th Edition. Some comments on AUT codes will be made. The paper will describe the latest phased array UT results, plus developments like automated set-ups and improved imaging using an increased number of zones. PipeWIZARD’s track record and capabilities will be illustrated.

scholarly journals Ultrasound Imaging Algorithm: Half-Matrix Focusing Method Based on Reciprocity

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Xufei Guo ◽  
Yan Han ◽  
Pengfei Nie
Keyword(s):  
Phased Array ◽  
Linear Array ◽  
Signal To Noise Ratio ◽  
Industrial Applications ◽  
Signal To Noise ◽  
Full Matrix ◽  
Calculation Process ◽  
Ultrasonic Phased Array ◽  
Data Capturing ◽  
Noise Ratio

The ultrasonic phased array total focusing method (TFM) has the advantages of high imaging signal-to-noise ratio (SNR) and high defect resolution, but the problem of large amount data capturing and processing limits its practical industrial applications. To reduce the imaging calculation demand of the total focusing method, a half-matrix focusing method (HFM) is proposed based on the acoustic reciprocity. The method simplifies the calculation process of full-matrix data capturing (FMC) and total focus imaging. The experimental results show that the signal obtained by the linear array transceiver sensor is highly consistent, and the imaging resolution and signal-to-noise ratio of the half-matrix focusing method are slightly lower than those of full-matrix focusing method and higher than those of the B-scan imaging. However, compared with TFM, data acquisition and computational efficiency using the HFM have been improved significantly.

scholarly journals Pipeline Girth Weld Inspections Using Ultrasonic Phased Arrays

2002 ◽  
Author(s):  
Michael Moles ◽  
Noe¨l Dube´ ◽  
Ed Ginzel
Keyword(s):  
Wall Thickness ◽  
Phased Array ◽  
Phased Arrays ◽  
Pipe Wall ◽  
Gas Pipeline ◽  
Pipe Wall Thickness ◽  
Safety Hazard ◽  
Lack Of Fusion ◽  
Track Record ◽  
Ultrasonic Phased Array

Mechanized ultrasonics is rapidly replacing radiography worldwide for gas pipeline girth weld inspections. Compared with radiography, mechanized ultrasonics is more reliable, faster, has better detectability for critical Lack of Fusion defects, and poses no safety hazard. Phased arrays present major improvements over conventional multiprobe ultrasonics, both for onshore and for offshore use. Probe pans are lighter and smaller, permitting less cutback; scans are quicker due to the smaller probe pan; phased arrays are considerably more flexible for changes in pipe dimensions or weld profiles, and for different scan patterns; phased arrays have great potential for the future, such as compensating for variations in pipe wall thickness or temperature. This paper describes the evaluation of the PipeWIZARD ultrasonic phased array system for girth weld inspections, using standard ASTM E-1961 Mechanized Ultrasonics set-ups. Some typical results will be shown. The paper will describe the latest phased array UT results, plus developments like automated set-ups and improved imaging using an increased number of zones. A brief comparison of E-1961 and the recent API 1104 19th Edition codes will be made, plus a summary of approvals and track record to date.

Sign in / Sign up

Export Citation Format

Share Document