scholarly journals Research on Cavitation Regions of Upstream Pumping Mechanical Seal Based on Dynamic Mesh Technique

2014 ◽  
Vol 6 ◽  
pp. 821058
Author(s):  
Huilong Chen ◽  
Qiangbo Wu ◽  
Cheng Xu ◽  
Muzi Zuo
Keyword(s):  
Experimental Data ◽  
Hydrodynamic Lubrication ◽  
Operating Conditions ◽  
Dynamic Mesh ◽  
Mechanical Seal ◽  
Cavitation Model ◽  
Cavitation Inception ◽  
Dynamic Mesh Technique ◽  
Lubrication Performance ◽  
Mesh Technique

In order to study the cavitation area of the Upstream Pumping Mechanical Seal, three-dimensional microgap inner flow field of the Upstream Pumping Mechanical Seal was simulated with multiphase flow cavitation model and dynamic mesh technique based on hydrodynamic lubrication theory. Furthermore, the simulated result was compared with the experimental data. The results show that the simulated result with the Zwart-Gerber-Belamri cavitation model was much closer to the experimental data. The area of cavitation inception mainly occurred at the concave side of the spiral groove and surrounding region without spiral grooves, which was nearly covered by the inner diameter to roots of grooves; in addition, the region near the surface of the stationary ring was primary cavitation location. The area of cavitation has little relationship with the medium pressure; however, it became larger following increasing rotating speed in the range of researched operating conditions. Moreover the boundary of cavitated area was transformed from smooth to rough, which occurred in similar film thickness. When cavitation number was decreasing, which was conducive to improving the lubrication performance of sealed auxiliary, it made the sealing stability decline.

Effects of double parabolic profiles with groove textures on the hydrodynamic lubrication performance of journal bearing under steady operating conditions

2020 ◽  
Vol 21 (3) ◽  
pp. 301
Author(s):  
Chongpei Liu ◽  
Wanyou Li ◽  
Xiqun Lu ◽  
Bin Zhao
Keyword(s):  
Journal Bearing ◽  
Hydrodynamic Lubrication ◽  
Operating Conditions ◽  
Lubricating Oil ◽  
Asperity Contact ◽  
Adiabatic Flow ◽  
Lubrication Performance ◽  
Load Carrying ◽  
Edge Wear ◽  
Journal Misalignment

The textures on the bushing surface have important effects on the performance of journal bearing. In this study, the effects of double parabolic profiles with groove textures on the hydrodynamic lubrication performance of journal bearing under steady operating conditions are investigated theoretically. The journal misalignment, asperity contact and thermal effects are considered, while the profile modifications due to running-in are neglected. The Winkler/Column model is used to calculate the elastic deformation of bushing surface and the adiabatic flow hypothesis is adopted to obtain the effective temperature of lubricating oil. The numerical solution is established by using finite difference and overrelaxation iterative methods, and the rupture zone of oil film is determined by Reynolds boundary conditions. The numerical results reveal that the double parabolic profiles with groove textures with proper location and geometric sizes can increase load carrying capacity and reduce friction loss under steady operating conditions, which effectively overcome the drawbacks of double parabolic profiles. This novel bushing profile may help to reduce the bushing edge wear and enhance the lubrication performance of journal bearing.

Simulating growth of ash deposit in boiler heat exchanger tube based on CFD dynamic mesh technique

Fuel ◽  
2020 ◽  
Vol 259 ◽  
pp. 116083 ◽  
Author(s):  
Zhimin Zheng ◽  
Wenming Yang ◽  
Peng Yu ◽  
Yongtie Cai ◽  
Hao Zhou ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Dynamic Mesh ◽  
Heat Exchanger Tube ◽  
Dynamic Mesh Technique ◽  
Ash Deposit ◽  
Mesh Technique ◽  
Exchanger Tube

Simulation on Three Dimensional Water-Exit Trajectory of Submarine Launched Missile

2013 ◽  
Vol 791-793 ◽  
pp. 1069-1072 ◽  
Author(s):  
Shao Zhu Wang ◽  
Han Ping Wang ◽  
Ming Yang ◽  
Lin Peng Wang ◽  
Guang Wei Wei
Keyword(s):  
Three Dimensional ◽  
Dynamic Mesh ◽  
Research Focus ◽  
Dynamic Mesh Technique ◽  
Mesh Technique ◽  
Trajectory Characteristic ◽  
Water Exit

Cool Launch project is an important launch mode of submarine launched missile, the water-exit trajectory characteristic of the missile in launching process becomes to research focus. Model of three dimensional water-exit trajectory of submarine launched missile was built based on dynamic mesh technique and simulation operation was carried out to obtain the characteristics of water-exit trajectory & attitude. The method adopted in the establishment of the model and the result has provided references to the research of water-exit trajectory.

Settling/rising of a foreign particle in solid-liquid fluidized beds: Application of dynamic mesh technique

2017 ◽  
Vol 170 ◽  
pp. 139-153 ◽  
Author(s):  
Swapnil V. Ghatage ◽  
Md. Shakhaoath Khan ◽  
Zhengbiao Peng ◽  
Elham Doroodchi ◽  
Behdad Moghtaderi ◽  
...  
Keyword(s):  
Fluidized Beds ◽  
Dynamic Mesh ◽  
Foreign Particle ◽  
Dynamic Mesh Technique ◽  
Solid Liquid ◽  
Mesh Technique

scholarly journals Numerical Simulation Study of Three-Dimensional Flow Field on Roots- Type Power Machine Based on Dynamic Mesh Technique

2015 ◽  
Vol 9 (1) ◽  
pp. 402-410
Author(s):  
Xiao Yanjun ◽  
Liu Yuxiang ◽  
Wang Dayuan ◽  
Li Chunxia
Keyword(s):  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Operating Conditions ◽  
Waste Heat Recovery System ◽  
Dynamic Mesh Technique ◽  
Power Machine ◽  
Recovery System ◽  
Type Power ◽  
Mesh Technique

Expander which drives an electromotor to generate electricity is the core of low-temperature waste heat recovery equipment. At present, domestic expanders on waste heat recovery system mostly arise from exploration, research and improvement on the existing models of screw expanders and scroll expanders, which have complex structures and high costs. For overcoming the shortcomings mentioned above, a new roots-type power machine is researched and designed. In this paper, the working fluid of low pressure waste heat is stimulated according to both the different operating conditions and the different intake and exhaust pressure and flow, and the changing process of internal flow field is simulated over the time period using dynamic mesh technique when the power machine is in rotating work. Besides, the pressure field, velocity field and graph of mass flow rate are analyzed with the simulation results, thus obtaining the conclusion of optimum operating conditions of the roots-type power machine to guide selection method in practice, that is, selecting appropriate roots-type power machines according to different types of waste heat in industrial production. These efforts can therefore provide strong theoretical guidance and foundation for the subsequent engineering practice of waste heat recovery system on roots-type power machine, and can have a profound impact on further recovery and utilization of low-grade energy.

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