检索结果-南通市图书馆

Effect of low-speed waterjet pressure on the rock-breaking performance of unsubmerged cavitating abrasive waterjet

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第4期21卷 2638-2649页

作者： Chen-Xing Fan Deng Li Yong Kang Hai-Tao Zhang Hubei Key Laboratory of waterjet Theory and New Technology Wuhan UniversityWuhan430072HubeiChina School of Power and Mechanical Engineering Wuhan UniversityWuhan430072HubeiChina

Unsubmerged cavitating abrasive waterjet(UCAWJ)has been shown to artificially create a submerged environment that produces shear cavitation,which effectively enhances rock-breaking *** shear cavitation generation and collapse intensity depend on the pressure difference between the intermediate high-speed abrasive waterjet and the coaxial low-speed ***,the effect of the pressure of the coaxial low-speed waterjet is *** this purpose,the effect of low-speed waterjet pressure on rock-breaking performance at different standoff distances was experimentally investigated,and the effects of erosion time and ruby nozzle diameter on erosion performance were ***,the micromorphology of the sandstone was observed at different *** results show that increased erosion time and ruby nozzle diameter can significantly improve the rock-breaking *** different standoff distances,the mass loss increases first and then decreases with the increase of low-speed waterjet pressure,the maximum mass loss is 10.4 g at a low-speed waterjet pressure of0.09 *** surface morphology of cavitation erosion was measured using a 3D profiler,the increase in both erosion depth and surface roughness indicated a significant increase in the intensity of the shear cavitation *** a low-speed waterjet pressure of 0.18 MPa,the cavitation erosion surface depth can reach 600μm with a roughness of 127μm.

关键词： Rock-breaking Coaxial low-speed waterjet pressure abrasive waterjet Cavitation Unsubmerged environment

Impact characteristics and stagnation formation on a solid surface by a supersonic abrasive waterjet

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2019年第4期1卷 43-61页

作者： Kunlapat Thongkaew Jun Wang Guan Heng Yeoh School of Mechanical and Manufacturing Engineering UNSW Sydney(The University of New South Wales)NSW 2052Australia

A computational fluid dynamics(CFD)study of the impact characteristics and stagnation formation on a solid target surface by an abrasive waterjet at supersonic velocities is presented to understand the impact process.A CFD model is developed and verified by experimental water and particle velocities and then used to simulate the jet impact *** trends of the stagnation formation and its effect on the jet flow with respect to the jetting and impacting parameters are amply *** is found that stagnation formation at the impact site increases with an increase in the impact time,nozzle standoff distance and nozzle diameter,while the initial peak velocity at the nozzle exit has little effect on the size of the stagnation *** is shown that stagnation markedly changes the water and particle flow direction,so that the particle impact angle is varied and the jet impact area is *** jet structure may be classified to have a free jet flow region,a jet deflection region with a stagnation zone and a wall jet ***,the stagnation affects significantly the waterjet and particle energy transferred to the target *** average particle velocity across the jet is reduced by approximately one third due to the damping effect of the stagnation under the conditions considered in this study.

关键词： abrasive waterjet jet impingement particle velocity flow characteristics impact phenomenon stagnation

A review on the erosion mechanisms in abrasive waterjet micromachining of brittle materials

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2019年第1期1卷 111-124页

作者： T Nguyen J Wang School of Mechanical and Manufacturing Engineering UNSW SydneyNSW 2052Australia

The fabrication of miniature structures on components with high-integrity surface quality represents one of the cutting edge technologies in the 21st *** materials used to construct such small structures are often *** other readily available technologies either cannot realise necessary precision or are *** waterjet(AWJ)is a favourable technology for the machining of difficult-to-machine ***,this technology is generally aimed at large stock removal.A reduction in the scale of this technology is an attractive avenue for meeting the pressing need of industry in the production of damage-free micro *** paper reviews some of the work that has been undertaken at UNSW Sydney about the development of such an AWJ technology,focusing on the system design currently employed to generate a micro abrasive jet,the erosion mechanisms associated with processing some typical brittle materials of both single-and *** models based on the findings are also *** review concludes on the viability of the technology and the prevailing trend in its development.

关键词： micro abrasive jet abrasive waterjet ductile erosion viscous flow difficult to machine materials

Universal Method for the Prediction of abrasive waterjet Performance in Mining

在线全文

学校读者我要写书评

暂无评论

Engineering 2017年第6期3卷 888-891页

作者： Eugene Averin OOO Skuratovsky Experimental Plant Tula 300911 Russia

abrasive waterjets （AWJs） can be used in extreme mining conditions for hard rock destruction, due to their ability to effectively cut difficult-to-machine materials with an absence of dust formation. They can also be used for explosion, intrinsic, and fire safety. Every destructible material can be considered as either ductile or brittle in terms of its fracture mechanics. Thus, there is a need for a method to predict the efficiency of cutting with AWJs that is highly accurate irrespective of material. This problem can be solved using the energy conservation approach, which states the proportionality between the material removal volume and the kinetic energy of AWJs. This paper describes a method based on this approach, along with recommendations on reaching the most effective level of destruction. Recommendations are provided regarding rational ranges of values for the relation of abrasive flow rate to water flow rate, standoff distance, and size of abrasive particles. I also provide a parameter to establish the threshold conditions for a material＇s destruction initiation based on the temporary-structural approach of fracture mechanics.

关键词： abrasive waterjet Energy conservation approach Depth of cut Fracture mechanics Threshold velocity Mining

Study of effect of surface finish inside abrasive waterjet focus tube using numerical simulation

在线全文

学校读者我要写书评

暂无评论

Study of effect of surface finish inside abrasive waterjet f...