期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
Attribute-driven Fuzzy Fault Tree Model for Adaptive Lubricant Failure Diagnosis
1
作者 Shuo Wang Yishi Chang +2 位作者 tonghai wu Zhidong Han Yaguo Lei 《Journal of Dynamics, Monitoring and Diagnostics》 2024年第3期207-215,共9页
Lubricant diagnosis serves as a crucial accordance for condition-based maintenance(CBM)involving oil changing and wear examination of critical parts in equipment.However,the accuracy of traditional end-to-end diagnosi... Lubricant diagnosis serves as a crucial accordance for condition-based maintenance(CBM)involving oil changing and wear examination of critical parts in equipment.However,the accuracy of traditional end-to-end diagnosis models is often limited by the inconsistency and random fluctuations in multiple monitoring indicators.To address this,an attribute-driven adaptive diagnosis method is developed,involving three attributes:physicochemical,contamination,and wear.Correspondingly,a fuzzy fault tree(termed FFT)-based model is constructed containing the logic correlations from monitoring indicators to attributes and to lubricant failures.In particular,inference rules are integrated to mitigate conflicts arising from the reverse degradation of multiple indicators.With this model,the lubricant conditions can be accurately assessed through rule-based reasoning.Furthermore,to enhance its intelligence,the model is dynamically optimized with lubricant analysis knowledge and monitoring data.For verification,the developed model is tested with lubricant samples from both the fatigue experiment and actual aero-engines.Fatigue experiments reveal that the proposed model can improve the lubricant diagnosis accuracy from 73.4%to 92.6%compared with the existing methods.While for the engine lubricant test,a high accuracy of 90%was achieved. 展开更多
关键词 lubricant failure diagnosis fuzzy fault tree attribute guidance rule reasoning
下载PDF
Performance Deterioration Analysis of the Used Gear Oil 被引量:1
2
作者 Qunfeng Zeng Guangneng Dong +1 位作者 Yanling Yang tonghai wu 《Advances in Chemical Engineering and Science》 2016年第2期67-75,共9页
In the present paper, we have investigated the tribological properties and microstructure of the used gear oil theoretically and experimentally. The deterioration process of the in-service gear lubricant oils was also... In the present paper, we have investigated the tribological properties and microstructure of the used gear oil theoretically and experimentally. The deterioration process of the in-service gear lubricant oils was also discussed. The viscosity and microstructure of oils running different mileages were analyzed by viscometer and Fourier Transform Infrared Spectroscopy (FTIR), respectively. In addition, the friction and wear behaviors of the friction pair of the GCr15 steel ball and disc were investigated using a ball on disc tribometer under different mileages’ gear oils lubrication conditions. These techniques give reproducible and reliable data with which to evaluate the severity of deterioration process of oils. The objective of this work is to understand the deterioration process of gear oil and analyze the influence of deterioration on the performance and microstructure of lubricant oils used in gear box. Possible explanations of deterioration process as well as its influence on friction and wear behaviors are also discussed. The results reveals the tribological properties of used oils depended on strongly the microstructure and its deterioration process of oil. 展开更多
关键词 Used Gear Oil Tribological Properties VISCOSITY FTIR DETERIORATION
下载PDF
Optimized Mask-RCNN model for particle chain segmentation based on improved online ferrograph sensor
3
作者 Shuo WANG Miao WAN +2 位作者 tonghai wu Zichen BAI Kunpeng WANG 《Friction》 SCIE EI CAS CSCD 2024年第6期1194-1213,共20页
Ferrograph-based wear debris analysis(WDA)provides significant information for wear fault analysis of mechanical equipment.After decades of offline application,this conventional technology is being driven by the onlin... Ferrograph-based wear debris analysis(WDA)provides significant information for wear fault analysis of mechanical equipment.After decades of offline application,this conventional technology is being driven by the online ferrograph sensor for real-time wear state monitoring.However,online ferrography has been greatly limited by the low imaging quality and segmentation accuracy of particle chains when analyzing degraded lubricant oils in practical applications.To address this issue,an integrated optimization method is developed that focuses on two aspects:the structural re-design of the online ferrograph sensor and the intelligent segmentation of particle chains.For enhancing the imaging quality of wear particles,the magnetic pole of the online ferrograph sensor is optimized to enable the imaging system directly observe wear particles without penetrating oils.Furthermore,a light source simulation model is established based on the light intensity distribution theory,and the LED installation parameters are determined for particle illumination uniformity in the online ferrograph sensor.On this basis,a Mask-RCNN-based segmentation model of particle chains is constructed by specifically establishing the region of interest(ROI)generation layer and the ROI align layer for the irregular particle morphology.With these measures,a new online ferrograph sensor is designed to enhance the image acquisition and information extraction of wear particles.For verification,the developed sensor is tested to collect particle images from different degraded oils,and the images are further handled with the Mask-RCNN-based model for particle feature extraction.Experimental results reveal that the optimized online ferrography can capture clear particle images even in highly-degraded lubricant oils,and the illumination uniformity reaches 90%in its imaging field.Most importantly,the statistical accuracy of wear particles has been improved from 67.2%to 94.1%. 展开更多
关键词 wear particle analysis online ferrography particle image acquisition particle chain segmentation
原文传递
Comparison-embedded evidence-CNN model for fuzzy assessment of wear severity using multi-dimensional surface images
4
作者 Tao SHAO Shuo WANG +2 位作者 Qinghua WANG tonghai wu Zhifu HUANG 《Friction》 SCIE EI CAS CSCD 2024年第6期1098-1118,共21页
Wear topography is a significant indicator of tribological behavior for the inspection of machine health conditions.An intelligent in-suit wear assessment method for random topography is here proposed.Three-dimension(... Wear topography is a significant indicator of tribological behavior for the inspection of machine health conditions.An intelligent in-suit wear assessment method for random topography is here proposed.Three-dimension(3D)topography is employed to address the uncertainties in wear evaluation.Initially,3D topography reconstruction from a worn surface is accomplished with photometric stereo vision(PSV).Then,the wear features are identified by a contrastive learning-based extraction network(WSFE-Net)including the relative and temporal prior knowledge of wear mechanisms.Furthermore,the typical wear degrees including mild,moderate,and severe are evaluated by a wear severity assessment network(WSA-Net)for the probability and its associated uncertainty based on subjective logic.By integrating the evidence information from 2D and 3D-damage surfaces with Dempster–Shafer(D–S)evidence,the uncertainty of severity assessment results is further reduced.The proposed model could constrain the uncertainty below 0.066 in the wear degree evaluation of a continuous wear experiment,which reflects the high credibility of the evaluation result. 展开更多
关键词 wear severity assessment contrastive learning subjective logic Dempster-Shafer(D-S)evidence theory
原文传递
Effect of carbon nanotubes on friction and wear of a piston ring and cylinder liner system under dry and lubricated conditions 被引量:4
5
作者 Zhinan ZHANG Jun LIU +1 位作者 tonghai wu Youbai XIE 《Friction》 CSCD 2017年第2期147-154,共8页
This study involves the application of carbon nanotubes (CNTs) to a piston ring and cylinder liner system in order to investigate their effect on friction and wear under dry and lubricated conditions.Carbon nanotubes ... This study involves the application of carbon nanotubes (CNTs) to a piston ring and cylinder liner system in order to investigate their effect on friction and wear under dry and lubricated conditions.Carbon nanotubes were used as a solid lubricant and lubricant additive in dry and lubricated conditions,respectively.Simulation and measurement of friction and wear were conducted using a reciprocating tribometer.Surface analysis was performed using a scanning electron microscope and an energy dispersive spectrometer.The results indicate that carbon nanotubes can considerably improve the tribological performance of a piston ring and cylinder liner system under dry sliding conditions,whereas improvement under lubricated conditions is not obvious.Under dry friction,the effective time of the CNTs is limited and the friction coefficient decreases with an increase in CNT content.Furthermore,the dominant wear mechanism during dry friction is adhesive. 展开更多
关键词 carbon nanotubes piston ring tribological behavior FRICTION WEAR
原文传递
A finite-element-aided ultrasonic method for measuring central oil-film thickness in a roller-raceway tribo-pair
6
作者 Pan DOU tonghai wu +4 位作者 Zhaopeng LUO Peiping YANG Zhongxiao PENG Min YU Tom REDDYHOFF 《Friction》 SCIE EI CAS CSCD 2022年第6期944-962,共19页
Roller bearings support heavy loads by riding on an ultra-thin oil film(between the roller and raceway),the thickness of which is critical as it reflects the lubrication performance.Ultrasonic interfacial reflection,w... Roller bearings support heavy loads by riding on an ultra-thin oil film(between the roller and raceway),the thickness of which is critical as it reflects the lubrication performance.Ultrasonic interfacial reflection,which facilitates the non-destructive measurement of oil-film thickness,has been widely studied.However,insufficient spatial resolution around the rolling line contact zone remains a barrier despite the use of miniature piezoelectric transducers.In this study,a finite-element-aided method is utilized to simulate wave propagation through a three-layered structure of roller-oil-raceway under elastohydrodynamic lubrication(EHL)with nonlinear characteristics of the i)deformed curvature of the cylindrical roller and ii)nonuniform distribution of the fluid bulk modulus along the circumference of the oil layer being considered.A load and speed-dependent look-up table is then developed to establish an accurate relationship between the overall reflection coefficient(directly measured by an embedded ultrasonic transducer)and objective variable of the central oil-film thickness.The proposed finite-element-aided method is verified experimentally in a rollerraceway test rig with the ultrasonically measured oil-flm thickness corresponding to the values calculated using the EHLtheory. 展开更多
关键词 ultrasonic measurement central oil-film thickness rolling line contact ray model finite-element-ISSN 2223-7690 CN10-1237/TH aided method
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部