The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Bruce W. Drinkwater - One of the best experts on this subject based on the ideXlab platform.
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thin oil Film Thickness distribution measurement using ultrasonic arrays
Ndt & E International, 2008Co-Authors: Jie Zhang, Bruce W. DrinkwaterAbstract:Abstract This paper describes an approach for calculating the oil-Film Thickness distribution in machine elements using an ultrasonic array, based on the measurement of normal and oblique incidence reflection coefficients. An experimental system is described in which a high-precision digital piezoelectric translator (DPT) is used to controllably displace the surfaces in a steel–oil–steel system and hence alter the oil-Film Thickness by a known amount. This three-layer system was chosen to be representative of a typical lubricated contact found in various machine elements such as bearings, gears and seals. In such lubricated systems the oil-Film Thickness typically ranges from 0.1 to 100 μm and this paper explores the range 2–9 μm experimentally. In the measurements described, reflection coefficients were obtained from transmitter–receiver pairs of an ultrasonic array. In this way, each reflection coefficient measurement corresponds to a point on the oil-Film and is related to a specific incidence angle. The oil-Film Thickness distributions were then extracted from these reflection coefficients via a multi-layer model. The measured oil-Film Thicknesses are shown to be in good quantitative agreement with the known displacements. This demonstrates the potential of this approach for the measurement of oil-Film Thickness distribution in lubricated contacts.
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Ultrasonic Phase and Amplitude and the Measurement of Oil Film Thickness
World Tribology Congress III Volume 1, 2005Co-Authors: Rob Dwyer-joyce, Tom Reddyhoff, Bruce W. DrinkwaterAbstract:The reflection of ultrasound at an oil Film can be used to determine the Film Thickness. A thin oil Film reflects less ultrasound than a thick Film. When the Film is thin there is a simple relationship between oil Film Thickness and the proportion of the wave amplitude reflected. The reflection coefficient is in fact a complex quantity with both magnitude and phase. A model for how both the phase and amplitude vary with oil Film Thickness (and the properties of the bearing materials) has been developed. It has been shown that both can be used to determine Film Thickness. Tests have been performed to determine the oil Film Thickness and explore the relationship between reflection amplitude and phase. Experiments are performed both on a static oil Film between flat plates, and on an operating journal bearing. Both methods provide a simple accurate method for the measurement of oil Film Thickness.
Jie Zhang - One of the best experts on this subject based on the ideXlab platform.
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thin oil Film Thickness distribution measurement using ultrasonic arrays
Ndt & E International, 2008Co-Authors: Jie Zhang, Bruce W. DrinkwaterAbstract:Abstract This paper describes an approach for calculating the oil-Film Thickness distribution in machine elements using an ultrasonic array, based on the measurement of normal and oblique incidence reflection coefficients. An experimental system is described in which a high-precision digital piezoelectric translator (DPT) is used to controllably displace the surfaces in a steel–oil–steel system and hence alter the oil-Film Thickness by a known amount. This three-layer system was chosen to be representative of a typical lubricated contact found in various machine elements such as bearings, gears and seals. In such lubricated systems the oil-Film Thickness typically ranges from 0.1 to 100 μm and this paper explores the range 2–9 μm experimentally. In the measurements described, reflection coefficients were obtained from transmitter–receiver pairs of an ultrasonic array. In this way, each reflection coefficient measurement corresponds to a point on the oil-Film and is related to a specific incidence angle. The oil-Film Thickness distributions were then extracted from these reflection coefficients via a multi-layer model. The measured oil-Film Thicknesses are shown to be in good quantitative agreement with the known displacements. This demonstrates the potential of this approach for the measurement of oil-Film Thickness distribution in lubricated contacts.
Kenji Sunaga - One of the best experts on this subject based on the ideXlab platform.
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Quartz microresonator sensors for monitoring thin Film Thickness
Proceedings of 1996 IEEE International Frequency Control Symposium, 1996Co-Authors: Hirofumi Kawashima, Kenji SunagaAbstract:This paper describes a quartz microresonator sensor for monitoring thin Film Thickness. A microresonator of tuning fork-type with stepped vibration bars vibrating in torsion which can be approximately regarded as "clamped-free bar" is very available for monitoring thin Film Thickness because it has excellent frequency temperature behavior over a wide temperature range of room temperature to high one of about 200/spl deg/C. In this paper, a relationship of resonant frequency to thin Film Thickness of Ak and Al is theoretically and experimentally clarified for the microresonator, so that the frequency deviation is proportional to the Film Thickness deposited on the top of the tuning arms, and the calculated values are in good agreement with the measured ones. This microresonator is, therefore, very available for monitoring thin Film Thickness.
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Quartz Microsensors for Monitoring Thin Film Thickness
Japanese Journal of Applied Physics, 1996Co-Authors: Hirofumi Kawashima, Kenji SunagaAbstract:This paper describes a quartz microsensor for monitoring thin Film Thickness. A microresonator of tuning fork-type with stepped vibration bars vibrating in torsion which can be approximately regarded as "clamped-free bar" is very available for monitoring thin Film Thickness because it has excellent frequency temperature behavior over a wide temperature range of room temperature to high one of about 200° C. In this paper, a relationship of resonant frequency to thin Film Thickness of Au and Al is theoretically and experimentally clarified for the microresonator, so that the frequency deviation is proportional to the Film Thickness deposited on the top of the tuning arms, and the calculated values are in good agreement with the measured ones. This microresonator is, therefore, very available for monitoring thin Film Thickness.
Hirofumi Kawashima - One of the best experts on this subject based on the ideXlab platform.
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Quartz microresonator sensors for monitoring thin Film Thickness
Proceedings of 1996 IEEE International Frequency Control Symposium, 1996Co-Authors: Hirofumi Kawashima, Kenji SunagaAbstract:This paper describes a quartz microresonator sensor for monitoring thin Film Thickness. A microresonator of tuning fork-type with stepped vibration bars vibrating in torsion which can be approximately regarded as "clamped-free bar" is very available for monitoring thin Film Thickness because it has excellent frequency temperature behavior over a wide temperature range of room temperature to high one of about 200/spl deg/C. In this paper, a relationship of resonant frequency to thin Film Thickness of Ak and Al is theoretically and experimentally clarified for the microresonator, so that the frequency deviation is proportional to the Film Thickness deposited on the top of the tuning arms, and the calculated values are in good agreement with the measured ones. This microresonator is, therefore, very available for monitoring thin Film Thickness.
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Quartz Microsensors for Monitoring Thin Film Thickness
Japanese Journal of Applied Physics, 1996Co-Authors: Hirofumi Kawashima, Kenji SunagaAbstract:This paper describes a quartz microsensor for monitoring thin Film Thickness. A microresonator of tuning fork-type with stepped vibration bars vibrating in torsion which can be approximately regarded as "clamped-free bar" is very available for monitoring thin Film Thickness because it has excellent frequency temperature behavior over a wide temperature range of room temperature to high one of about 200° C. In this paper, a relationship of resonant frequency to thin Film Thickness of Au and Al is theoretically and experimentally clarified for the microresonator, so that the frequency deviation is proportional to the Film Thickness deposited on the top of the tuning arms, and the calculated values are in good agreement with the measured ones. This microresonator is, therefore, very available for monitoring thin Film Thickness.
So Toda - One of the best experts on this subject based on the ideXlab platform.
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MEASUREMENT OF THIN OIL Film Thickness USING ULTRASONIC TECHNIQUE
Modern Physics Letters B, 2008Co-Authors: Akitoshi Takeuchi, Seiichi Terada, So TodaAbstract:An application of ultrasonic technique is attempted for the purpose of measuring thin oil Film Thickness between two surfaces. The amplitude of the wave reflected from the boundary is vary depending on Film Thickness, because the ultrasonic wave emitted to the interface between two surfaces does multiple reflection and interference in oil Film. Quantitative measurement of oil Film Thickness then can be possible. For instance, it is possible to measure the submicron Film Thickness which exists near the point contact formed by convex glass and plate with high frequency probe. And it is confirmed that the oil Film Thickness estimated from the echo height agrees with the Film Thickness decided by the curvature of the lens or obtained by the optical interference method, even if it is 100 nm. On the other hand, the Thickness of oil Film between cylinder and piston ring can be easily measured by setting the small ultrasonic probe on the back of piston ring. For example, the influence of the second ring and oil ring for the behavior of an oil Film formed on a top ring is able to evaluate quantitatively. As mentioned above, it is cleared that quantitative evaluation of thin Film Thickness is possible with investigating the echo height obtained by ultrasonic wave pulse reflection method.
