Flow divider / combiner valve divides / combines flow in a predetermined ratio regardless of the load pressures at the outlet ports. It is used to synchronize the movements of hydraulic actuators under adverse conditions. There are two types of flow divider/combiners, sliding spool and rotary (usually gear), where each type has its own set of performance characteristics such as flow range, pressure capability, accuracy and application parameters. In the present work, a mathematical model for interlocked spools of a cartridge design flow divider valve has been carried out to study static and dynamic characteristics of the flow divider valve at different load pressures. The model has been verified by direct comparisons with the experimental results. Comparison between the interlocked (split) spool and a single spool sliding flow divider has been performed. The comparison between experimental and simulated model for the interlocked flow divider has showed a good agreement for the studied system pressures up to 50 bars to validate the theoretical model results. Theoretical comparison has been performed between the interlocked split spool and the single spool flow divider performances parameter. It has been found that the interlocked split flow divider has a low inertia effect which enhanced valve response at the studied load pressure regimes.

/pdf/experimental-and-theoretical-investigation-of-an-interlocked-18qbmlnnhe.pdf

Experimental and Theoretical Investigation of an Interlocked spools Flow Divider

In order to solve the problem that the measurement accuracy of FBG sensors used in the ring type dynamometer is vulnerable to be influenced by temperature fluctuations and others, a method for the temperature compensation of ring type dynamometer is necessary. A method that using wavelength multiplexed technology of fiber Bragg grating to test temperature and strain simultaneously has been proposed. This paper studies temperature characteristics of FBG sensors and annulus elastic body. Temperature calibration experiment which is used to obtain the temperature characteristic function of FBG sensors and annulus elastic body has also been done. Through the analysis of data, the temperature characteristic of ring type dynamometer has been obtained, and it owns good linearity. By using the temperature characteristic of ring type dynamometer, the effect of temperature fluctuation on the measurement accuracy can be compensated, which can enhance the cutting force measurement precision of ring type dynamometer.

Temperature characteristic of ring type dynamometer based on FBG sensors

The "digital reservoir" is usually understood as describing the whole reservoir with digital information technology to make it serve the human existence and development furthest. Strictly speaking, the "digital reservoir" is referred to describing vast information of the reservoir in different dimension and space-time by RS, GPS, GIS, telemetry, remote-control and virtual reality technology based on computer, multi-media, large-scale memory and wide-band networks technology for the human existence, development and daily work, life and entertainment. The core of "digital reservoir" is to realize the intelligence and visibility of vast information of the reservoir through computers and networks. The dam is main building of reservoir, whose safety concerns reservoir and people's safety. Safety monitoring is important way guaranteeing the dam's safety, which controls the dam's running through collecting the dam's information concerned and developing trend. Safety monitoring of the dam is the process from collection and processing of initial safety information to forming safety concept in the brain. The paper mainly researches information collection and processing of the dam by digital means.

Information collection and processing of dam distortion in digital reservoir system

Firstly, the concept of digital reservoir is proposed and discussed in the paper, then the method how to monitor dam’s state by digital means and how to transmit the monitoring data by GPRS technology is presented, and the method can monitor the dam’s state in real time and its advantages such as real-time, visibility, visualization are analyzed later. The indicators reflecting the safety of dam are selected, and the method how to build mathematical model to real time monitor the safety and the procedure of modeling in engineering are given. At last, the above proposed method is demonstrated in Xueye reservoir, Lai Wu, Shandong Province. As a result, it is prove that the monitoring technology of the dam is effective.

/pdf/research-on-monitoring-technology-of-digital-reservoir-16qy23sfm6.pdf

Research on Monitoring Technology of Digital Reservoir

The embedding technology of the FBG sensor in concrete structure has been studied based on FBG sensing principle. The monitoring technology of FBG sensor for the changes of the stress and strain within the concrete structure under the applied load and the comparative experiment of the FBG senor and the common vibrating wires sensors in concrete beam have been investigated. The results show that the FBG sensors, which can realize a real-time and on-line monitoring, have higher measurement accuracy, better interference resistance,long-term stability and simple structure. Thus, the FBG sensor has an extensive prospect in dam safety engineering.

Study on Application of FBG Sensing Technology for Dam Safety Monitoring

An Integrated Flow Divider/Combiner Valve Design, Part 1

The embedded module network numerical control system is demonstrated in the paper applying the latest development of embedded technology, network and communication (including industry network and communication technology). Besides, the modular development of the systempsilas software and hardware platform is demonstrated with details. By exploiting the modular design method, the embedded module network numerical control system would possess the advantages of high performance, low cost, effective resource utilization, flexible structure, easy to expand, open structure. Furthermore, it would meet the requirement of numerical control machining under the environment of network digital manufacturing better, and it can also work out the problems confronted by numerical control based on industry PC. Besides, more importantly, the convenient long-distance control and inspection will be better realized through embedded Web. What is more, this system will be beneficial to the further development of numerical control technology over developing methods and directions.

Research on and development of embedded module network numerical Control

The embedded module network numerical control system is demonstrated in the paper applying the latest development of embedded technology, network and communication (including industry network and communication technology). Besides, the modular development of the system's software and hardware platform is demonstrated with details. By exploiting the modular design method, the embedded module network numerical control system would possess the advantages of high performance, low cost, effective resource utilization, flexible structure, easy to expand, open structure. Furthermore, it would meet the requirement of numerical control machining under the environment of network digital manufacturing better, and it can also work out the problems confronted by numerical control based on industry PC. Besides, more importantly, the convenient long-distance control and inspection will be better realized through embedded web. What is more, this system will be beneficial to the further development of numerical control technology over developing methods and directions.

http://ieeexplore.ieee.org/iel5/4762424/4776129/04776245.pdf

Xin Si-jin

Papers

Study on Application of FBG Sensing Technology for Dam Safety Monitoring

An Integrated Flow Divider/Combiner Valve Design, Part 1

Research on and development of embedded module network numerical Control

Research on and Development ofEmbedded Module Network Numerical Control