The Experts below are selected from a list of 4506 Experts worldwide ranked by ideXlab platform
Qian Cong - One of the best experts on this subject based on the ideXlab platform.
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Effects of cylindrical pit array on tribological property of Piston–Cylinder sleeve friction pair in a BW-250 slime Pump
Tribology International, 2020Co-Authors: Tianyu Gao, Zhang Hong, Xu Jin, Ma Boshuai, Qian CongAbstract:Abstract This study designed a bio-inspired Piston with a cylindrical pit array according to the BW-250 slime Pump Piston based on the surface structure of earthworm and leech. The friction was tested and analyzed. The friction pair mechanic system was modeled for finite element analysis, and the oil film test was supplemented. Results demonstrate that the bio-inspired Piston show a lower friction force than the standard Piston and a drag reduction rate that is above 10%. Cylindrical pit array can reduce the flow velocity of lubricating oil and increase the oil film pressure. The length and thickness of the oil film over the bio-inspired Piston are higher than those of standard Pistons.
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sealing performance of bionic striped mud Pump Piston
Advances in Materials Science and Engineering, 2019Co-Authors: Qian Cong, Weijun TianAbstract:The mud Pump Piston is a key part for providing mud circulation, but its sealing performance often fails under complex working conditions, which shorten its service life. Inspired by the ring segment structure of earthworms, the bionic striped structure on surfaces of the mud Pump Piston (BW-160) was designed and machined, and the sealing performances of the bionic striped Piston and the standard Piston were tested on a sealing performance testing bench. It was found the bionic striped structure efficiently enhanced the sealing performance of the mud Pump Piston, while the stripe depth and the angle between the stripes and lateral of the Piston both significantly affected the sealing performance. The structure with a stripe depth of 2 mm and angle of 90° showed the best sealing performance, which was 90.79% higher than the standard Piston. The sealing mechanism showed the striped structure increased the breadth and area of contact sealing between the Piston and the cylinder liner. Meanwhile, the striped structure significantly intercepted the early leaked liquid and led to the refluxing rotation of the leaked liquid at the striped structure, reducing the leakage rate.
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wear performance of bionic dimpled shape Pistons of mud Pump
Advances in Materials Science and Engineering, 2017Co-Authors: Xuejing Cheng, Shaofeng Ru, Qian CongAbstract:The Piston is one of the parts that most easily become worn out and experience failure in mud Pumps for well drilling. By imitating the body surface morphology of the dung beetle, this paper proposed a new type (BW-160) of mud Pump Piston that had a dimpled shape in the regular layout on the Piston leather cup surface and carried out a performance test on the self-built test rig. Firstly, the influence of different dimple diameters on the service life of the Piston was analyzed. Secondly, the analysis of the influence of the dimple central included angle on the service life of the Piston under the same dimple area density was obtained. Thirdly, the wear of the new type of Piston under the same wear time was analyzed. The experimental results indicated that the service life of the Piston with dimples on the surface was longer than that of L-Standard Pistons, and the maximum increase in the value of service life was 92.06%. Finally, the Workbench module of the software ANSYS was used to discuss the wear-resisting mechanism of the new type of Piston.
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wear performance of bionic strip shaped mud Pump Pistons
Proceedings of the Institution of Mechanical Engineers Part C: Journal of Mechanical Engineering Science, 2017Co-Authors: X J Cheng, S F Ru, Qian CongAbstract:The service life of mud Pump Pistons may be extended by imitating the body surface morphology of earthworms. To achieve this solution, bionic strip structures of various sizes are processed on the working surface of a BW-160 mud Pump Piston. The service lives of standard and bionic Pistons are compared under experimental conditions. Results show that the bionic strip structure clearly improves the service life of mud Pump Pistons. The influence of the width of a bionic Piston strip is greater than that of strip spacing. The bionic strip should not be too small or large because size could have negligible or deleterious effects on service life, respectively. The optimal structure parameters of a bionic strip Piston when the optimal contact area between the Piston and the cylinder liner is 73.5% are a strip width of 3 mm, strip spacing of 3 mm, and strip number of 3. These parameters improve Piston service life by 81.5%. Finite element analysis simulations of wear demonstrate that the bionic strip can change...
Sergio M. Savaresi - One of the best experts on this subject based on the ideXlab platform.
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Adaptive position–pressure control of a brake by wire actuator for sport motorcycles
European Journal of Control, 2014Co-Authors: Fabio Todeschini, Matteo Corno, Giulio Panzani, Sergio M. SavaresiAbstract:Abstract In this work the control of an electro-hydraulic brake by wire system is presented. The actuator is composed of an electric motor, a mechanical transmission, a hydraulic Pump and a pipeline connected to the brake caliper. The highly nonlinear, time-varying relationship between Pump Piston position and plant pressure ismodelled, showing how the closed loop performances degrade without considering it. A hybrid position–pressure switching controller that aims at coping with the mentioned non-linearity is proposed. A position–pressure map estimation algorithm is introduced; this allows one to make the closed loop system robust with respect to temperature variation and brake pad wear.
Philip A. Davies - One of the best experts on this subject based on the ideXlab platform.
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A solar-powered reverse osmosis system for high recovery of freshwater from saline groundwater
Desalination, 2011Co-Authors: Philip A. DaviesAbstract:Desalination of groundwater is essential in arid regions that are remote from both seawater and freshwater resources. Desirable features of a groundwater desalination system include a high recovery ratio, operation from a sustainable energy source such as solar, and high water output per unit of energy and land. Here we propose a new system that uses a solar-Rankine cycle to drive reverse osmosis (RO). The working fluid such as steam is expanded against a power Piston that actuates a Pump Piston which in turn pressurises the saline water thus passing it through RO membranes. A reciprocating crank mechanism is used to equalise the forces between the two Pistons. The choice of batch mode in preference to continuous flow permits maximum energy recovery and minimal concentration polarisation in the vicinity of the RO membrane. This study analyses the sizing and efficiency of the crank mechanism, quantifies energy losses in the RO separation and predicts the overall performance. For example, a system using a field of linear Fresnel collectors occupying 1000 m2 of land and raising steam at 200 °C and 15.5 bar could desalinate 350 m3/day from saline water containing 5000 ppm of sodium chloride with a recovery ratio of 0.7.
Fabio Todeschini - One of the best experts on this subject based on the ideXlab platform.
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Adaptive position–pressure control of a brake by wire actuator for sport motorcycles
European Journal of Control, 2014Co-Authors: Fabio Todeschini, Matteo Corno, Giulio Panzani, Sergio M. SavaresiAbstract:Abstract In this work the control of an electro-hydraulic brake by wire system is presented. The actuator is composed of an electric motor, a mechanical transmission, a hydraulic Pump and a pipeline connected to the brake caliper. The highly nonlinear, time-varying relationship between Pump Piston position and plant pressure ismodelled, showing how the closed loop performances degrade without considering it. A hybrid position–pressure switching controller that aims at coping with the mentioned non-linearity is proposed. A position–pressure map estimation algorithm is introduced; this allows one to make the closed loop system robust with respect to temperature variation and brake pad wear.
Matteo Corno - One of the best experts on this subject based on the ideXlab platform.
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Adaptive position–pressure control of a brake by wire actuator for sport motorcycles
European Journal of Control, 2014Co-Authors: Fabio Todeschini, Matteo Corno, Giulio Panzani, Sergio M. SavaresiAbstract:Abstract In this work the control of an electro-hydraulic brake by wire system is presented. The actuator is composed of an electric motor, a mechanical transmission, a hydraulic Pump and a pipeline connected to the brake caliper. The highly nonlinear, time-varying relationship between Pump Piston position and plant pressure ismodelled, showing how the closed loop performances degrade without considering it. A hybrid position–pressure switching controller that aims at coping with the mentioned non-linearity is proposed. A position–pressure map estimation algorithm is introduced; this allows one to make the closed loop system robust with respect to temperature variation and brake pad wear.
