Based on the recently quick-developing time-frequency analysis (TFA)technique and virtual instrument (VI) technique, a virtual instrument in characteristic analysis ofrotating machinery is researched and developed suc...Based on the recently quick-developing time-frequency analysis (TFA)technique and virtual instrument (VI) technique, a virtual instrument in characteristic analysis ofrotating machinery is researched and developed successfully. By utilizing instantaneous frequencyestimation (IFE) theoretics of TFA technique, and based on IFE of peak searching on thetime-frequency spectrum, order analysis (OA) functions is put forward and implemented, such as orderspectrum, order spectrum matrix, order tracking, order tracking filtering, and order componentextraction, etc. Unlike the home and abroad existing popular characteristic analyzers, which needkey phasing devices such as shaft encoder, phase-locked loop (PLL), phase-locked multiple frequency,tachometer, etc, to implement constant angle sampling directly or indirectly, whereas thisinstrument only uses the vibration signal of rotating machinery to carry out OA. This instrumentmakes up the shortage of these traditional instruments in analyzing the non-stationary signal ofrun-up and run-down process of rotating machinery. Therefore, it is a great breakthrough for theexisting order analyzers.展开更多
The piezoelectric pump with nozzle/diffuser-elements, which oscillating formdiffering from regular volumetric reciprocating or rotating pumps because there arenozzle/diffuser-elements substituted for regular valves, i...The piezoelectric pump with nozzle/diffuser-elements, which oscillating formdiffering from regular volumetric reciprocating or rotating pumps because there arenozzle/diffuser-elements substituted for regular valves, is a new type pump whose actuator is apiezoelectric ceramal part with verse piezoelectric effect In recent year, piezoelectric pump ispaid increasing attention to because it is an ideal candidate in application in such area as medicalhealth, mechanical tools and micro-mechanism. The fundamental research on it, however, is still notmade through. Focuses on the phenomenon of different directions of flow among Germany pump, Chinesepump and Swiss pump, which are all fitted with nozzle/diffuser-elements, and analyzes the coneangle of nozzle/diffuser-elements based on the flow equation of valve-less piezoelectric pump withnozzle/diffuser-elements. As a result, the concepts of diffuser toss coefficient and losscoefficient are introduced to explain these phenomena, from which a discussion is given on theoptimization of the cone angle of nozzle/diffuser-element aiming at the maximum of pump flow.展开更多
Oil monitoring and vibration monitoring are two principal techniques for mechanical fault diagnosis and condition monitoring at present. They monitor the mechanical condition by different approaches, nevertheless, oil...Oil monitoring and vibration monitoring are two principal techniques for mechanical fault diagnosis and condition monitoring at present. They monitor the mechanical condition by different approaches, nevertheless, oil and vibration monitoring are related in information collecting and processing. In the same mechanical system, the information obtained from the same information source can be described with the same expression form. The expressions are constituted of a structure matrix, a relative matrix and a system matrix. For oil and vibration monitoring, the information source is correlation and the collection is independent and complementary. And oil monitoring and vibration monitoring have the same process method when they yield their information. This research has provided a reasonable and useful approach to combine oil monitoring and vibration monitoring.展开更多
文摘Based on the recently quick-developing time-frequency analysis (TFA)technique and virtual instrument (VI) technique, a virtual instrument in characteristic analysis ofrotating machinery is researched and developed successfully. By utilizing instantaneous frequencyestimation (IFE) theoretics of TFA technique, and based on IFE of peak searching on thetime-frequency spectrum, order analysis (OA) functions is put forward and implemented, such as orderspectrum, order spectrum matrix, order tracking, order tracking filtering, and order componentextraction, etc. Unlike the home and abroad existing popular characteristic analyzers, which needkey phasing devices such as shaft encoder, phase-locked loop (PLL), phase-locked multiple frequency,tachometer, etc, to implement constant angle sampling directly or indirectly, whereas thisinstrument only uses the vibration signal of rotating machinery to carry out OA. This instrumentmakes up the shortage of these traditional instruments in analyzing the non-stationary signal ofrun-up and run-down process of rotating machinery. Therefore, it is a great breakthrough for theexisting order analyzers.
基金This project is supported by Municipal Natural Science Foundation of Beiiing , China (No.3032005).
文摘The piezoelectric pump with nozzle/diffuser-elements, which oscillating formdiffering from regular volumetric reciprocating or rotating pumps because there arenozzle/diffuser-elements substituted for regular valves, is a new type pump whose actuator is apiezoelectric ceramal part with verse piezoelectric effect In recent year, piezoelectric pump ispaid increasing attention to because it is an ideal candidate in application in such area as medicalhealth, mechanical tools and micro-mechanism. The fundamental research on it, however, is still notmade through. Focuses on the phenomenon of different directions of flow among Germany pump, Chinesepump and Swiss pump, which are all fitted with nozzle/diffuser-elements, and analyzes the coneangle of nozzle/diffuser-elements based on the flow equation of valve-less piezoelectric pump withnozzle/diffuser-elements. As a result, the concepts of diffuser toss coefficient and losscoefficient are introduced to explain these phenomena, from which a discussion is given on theoptimization of the cone angle of nozzle/diffuser-element aiming at the maximum of pump flow.
文摘Oil monitoring and vibration monitoring are two principal techniques for mechanical fault diagnosis and condition monitoring at present. They monitor the mechanical condition by different approaches, nevertheless, oil and vibration monitoring are related in information collecting and processing. In the same mechanical system, the information obtained from the same information source can be described with the same expression form. The expressions are constituted of a structure matrix, a relative matrix and a system matrix. For oil and vibration monitoring, the information source is correlation and the collection is independent and complementary. And oil monitoring and vibration monitoring have the same process method when they yield their information. This research has provided a reasonable and useful approach to combine oil monitoring and vibration monitoring.
