Oil Debris Detection Using Capacitance and Ultrasonic Measurements

Author(s):  
J. Zhe ◽  
F. K. Choy ◽  
S. V. Murali ◽  
M. A. Sarangi ◽  
R. Wilfong

This paper aims at the use of a capacitance sensing approach using a RLC meter to detect oil debris contents and experimental results are compared to those obtained using an ultrasonic device. It was found that both capacitance and ultrasonic measurement can both detect particles as small as 4 mils (101 μm) in diameter. Experimental results show that the measured capacitance increases linearly with the increase of particle size while the ultrasonic wave amplitude decreases linearly with the increase of particle size. While some measurable differences can be detected by both capacitance and ultrasonic measurements between the ferrous and the nonferrous particles, a systematic difference between the data point cannot be developed. In addition, the existence of nonconductive particles cannot be readily detected using the capacitance measurements but their existence can be observed by the ultrasonic measurement.

Author(s):  
S. V. Murali ◽  
F. K. Choy ◽  
J. Zhe ◽  
J. Carletta ◽  
X. Xia

This paper describes a capacitance sensing method to detect oil debris contents. Experimental investigations are conducted for both static and dynamic measurements. Static measurements are performed by inserting small metal wires into the oil sample between the two plate electrodes of a capacitor. With a gap of 7mm between the electrodes, it was found that the capacitance measurement can detect metal wires as small as 4 mils (101 μm) in diameter. While measurements of ferrous and the non-ferrous wires show certain measurable differences, a systematic difference between the two sets of measurements cannot be established. The dynamic measurements were conducted by measuring the changes in capacitance between two plate electrodes when a small particle was dropped into the oil between the two electrodes. The passage of a metal particle can be dynamically detected. It is expected that smaller metal debris particles can be detected by reducing the spacing between the two electrode plates in microchannels.


2010 ◽  
Vol 177 ◽  
pp. 526-529 ◽  
Author(s):  
Zhi Qiang Li ◽  
Zong Hui Zhou ◽  
Dong Yu Xu ◽  
Jing Hua Yu

The influences of particle size and mixing content of coarse cement on the self-healing ability of concrete were researched by ultrasonic method. Damaged degree was measured through the decrease of ultrasonic head wave amplitude (UHA) before and after loading. The relationship between damaged degree and self-healing ratio of concrete was built based on the experimental results as well as the relationship between cement diameter and self-healing ratio of concrete. Analyzing results show that UHA can evaluate the damaged degree of concrete clearly. There exists a damaged threshold of the concrete during loading. Under the same mixing content of coarse cement, when the damaged degree is higher than the threshold, the self-healing ratio of concrete decreases with the increase of damaged degree and increases with the increase of coarse cement diameter, however, while the damaged degree is less than the threshold, the self-healing ratio of concrete increases with both the increase of damaged degree and coarse cement diameter.


1975 ◽  
Vol 58 (2) ◽  
pp. 471-474 ◽  
Author(s):  
Kenneth Lazara ◽  
Jose M. Zayas ◽  
Alfred Zajac
Keyword(s):  

2018 ◽  
Vol 10 (9) ◽  
pp. 3005
Author(s):  
Ling-feng Xie ◽  
Shu-liang Zou ◽  
Xiang-yang Li ◽  
Chang-shou Hong ◽  
Hong Wang ◽  
...  

Radon is internationally recognized as one of the seven seismic precursors. A self-assembly ultrasonic generator and experimental apparatus for radon measurement were utilized to explore the radon exhalation regularities of water-bearing porous media under different ultrasonic intensities. The experimental results showed that there was a coupling relationship among radon exhalation rate, moisture content, and ultrasonic frequency. With the increase of the frequency of the ultrasonic wave, its effect on the promotion of radon exhalation rate was found to be a more obviously positive linear correlation. The radon exhalation rate, which could climb to a maximum value of 0.179 Bq·m−2·s−1 in a naturally air-dried sample, increased at first and then decreased along with increased moisture content. Moreover, this study found that the ultrasonic wave had the most remarkable promoting effects on the radon exhalation rate of porous media with high moisture content, and there is a positive linear correlation between the growth rate of the radon exhalation rate and moisture content. The experimental results could provide a beneficial reference for the continual monitoring of radon in a seismically active belt and an explanation of radon anomalies; however, the proposed experimental model was simplified, so further insights are strictly required for a reliable correlation with the real monitoring of radon in a seismically active belt.


2022 ◽  
pp. 1-32
Author(s):  
Hassan Salem ◽  
Ehab Mina ◽  
Raouf Abdelmessih ◽  
Tarek Mekhail

Abstract The cooling fluid is a key factor in cooling photovoltaic (PV) panels especially in the case of concentrated irradiance. Maintaining the panel at low temperature increases its efficiency. This paper investigates the usage of water-Al2O3 as a nanofluid for achieving the required cooling process. The particle concentrations and sizes are investigated to record their effect on heat transfer and pressure drop in the developing and developed regions. The research was performed using ANSYS CFD software with two different approaches: the single phase with average properties, and the discrete phase with the Eulerian-Lagrangian frame-work. Both approaches are compared to experimental results found in the literature. Both approaches show good agreement with the experimental results, with some advantage for the single-phase model both in processing time and in predicting heat transfer in the concentration range of 1-6% by volume. It was shown that, the heat transfer coefficient is greatly enhanced by increasing the particle concentration or decreasing the particle size. On the other hand, the usage of nanofluid causes a severe increase in the pumping power, especially with the increase in concentration and the reduction in particle size. Thus, a system optimization was suggested in order to raise the overall system efficiency for photovoltaic applications.


Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2564 ◽  
Author(s):  
Nan Li ◽  
Mingchen Cao ◽  
Hangben Du ◽  
Cunfu He ◽  
Bin Wu

Grouting ducts (containing steel strands) are widely used to increase the structural strengths of infrastructures. The determination of the steel strand’s integrity inside of ducts and the grouting quality are important for a strength evaluation of the structure. In this study, a capacitive sensing technique was applied to identify the cross-sectional distribution of the steel strands. The distribution was expressed in polar coordinates in an external post-tensioned pre-stressed duct model. An improved capacitive sensor structure was designed, which consisted of four electrodes, and different electrode-pairs were used to determine various locations’ information of the steel strands. Two rounds of measurements were conducted using the designed sensor to detect the angle (θ) and center distance (r) of the steel strand in the duct. The simulated and experimental results are presented and analyzed. In general, it is difficult to locate the angle of a steel strand directly from first-round capacitance measurements by analyzing the experimental results. Our method based on Q-factor analysis was presented for the position detection of a steel bar in an external post-tensioned pre-stressed duct. The center distance of the steel bar could be identified by second-round capacitance measurements. The processed results verified the effectiveness of the proposed capacitive sensor structure. Thus, the capacitive sensing technique exhibited potential for steel strand cross-section distribution detection in external post-tensioned pre-stressed ducts.


2008 ◽  
Vol 273-276 ◽  
pp. 474-478
Author(s):  
I.K. Park ◽  
J.H. Kim ◽  
B.T. Min ◽  
S.H. Hong ◽  
H.D. Kim ◽  
...  

The TEXAS-V code was tuned for TROI-13 and used for analyzing the parametric findings of the TROI experiments. The calculations for the melt composition are relatively similar to the TROI experimental results, in which the melt composition has quite an effect on the steam explosion occurrence probabilities and a steam explosion itself. The void fraction difference due to a particle size difference appears to cause this composition dependency of a steam explosion. The water depth effect in the TEXAS-V code seems to be consistent with the TROI experiments to some degree. The water area effect of the TEXAS-V calculations isn’t exactly harmonious with that of the TROI experiments. This indicates that TEXAS-V code as a 1-dimensional code or as a numerical steam explosion has a limitation in estimating an area effect. The experimental information on the particle size and the void fraction during mixing is very helpful for a verification of this relation.


Author(s):  
Meng Ji ◽  
Ke Chen ◽  
Yunxiang You ◽  
Ruirui Zhang

Abstract Although ocean structures are complex, they all can be disassembled into a number of simple-shaped parts. One common shape is the slender body mentioned in this paper, and we focus on studying the mechanism of this shape. Experiments were carried out to study features of wave loads exerted by internal solitary waves (ISWs) on a submerged slender body. ISWs were generated by a piston-type wave maker in a large-type density stratified two-layer fluid wave flume. Using a three-component force transducer, the force variation of three degree of freedom (DOF) on the model was recorded. A satisfactory prediction method is established for ISWs on a submerged slender body based on internal solitary wave theory, Morison equation and pressure integral. Calculations based on this new prediction method are in good agreement with the experimental results. The experimental results and calculations show that, different incident angles, wave amplitude and layer thickness ratio have great effects on the wave loads, especially transverse incident waves bring much more severely influence. Besides the forces increase linearly with the wave amplitude becoming larger, and the maximums of the horizontal forces increase with the layer thickness ratio increasing.


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