MechanicsPub Date : 2024-02-23DOI: 10.5755/j02.mech.34089
Ruikun Niu, Zhongming Wu, Huantao Wang, Li Sun
{"title":"Effect of Vibration Direction on Vibration-Assisted Fixed Abrasive Polishing","authors":"Ruikun Niu, Zhongming Wu, Huantao Wang, Li Sun","doi":"10.5755/j02.mech.34089","DOIUrl":"https://doi.org/10.5755/j02.mech.34089","url":null,"abstract":"In order to study the effect of vibration direction on vibration-assisted fixed abrasive polishing and explore the influence rule of vibration direction on material removal rate and workpiece surface quality, a single abrasive particle vibration-assisted fixed abrasive polishing model was established to study the effect of axial and radial vibration on workpiece profile depth, surface morphology, etc. And the experiments of vibration-assisted fixed abrasive polishing in different vibration directions were carried out. The results show that axial vibration auxiliary polishing can greatly advance the processing efficiency, and improve the workpiece material removal rate by 27.6%; radial vibration auxiliary polishing can achieve better surface quality, and reduces the surface roughness by 59.8%.","PeriodicalId":511970,"journal":{"name":"Mechanics","volume":"24 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140437870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MechanicsPub Date : 2024-02-23DOI: 10.5755/j02.mech.34137
Chao Wang, Yongbin Zhang
{"title":"Multiscale Elastohydrodynamic Wedge-Platform Thrust Bearing with Ultra Low Clearance","authors":"Chao Wang, Yongbin Zhang","doi":"10.5755/j02.mech.34137","DOIUrl":"https://doi.org/10.5755/j02.mech.34137","url":null,"abstract":"The effect of the surface elastic deformation is investigated by the multiscale approach in the hydrodynamic wedge-platform thrust bearing with the ultra low clearance on the 1nm scale, by incorporating both the non-continuum pure adsorbed layer flow and the multiscale “sandwich” film flow. The pure adsorbed layer flow in ultra small surface separations is described by the non-continuum nanoscale flow equation; The “sandwich” film flow is described by the multiscale flow equations respectively for the adsorbed layer flow and the intermediate continuum fluid flow. The numerical calculation results show that in the studied bearing, the effect of the surface elastic deformation is normally significant, it pronouncedly reduces the maximum film pressure, greatly changes both the film pressure profile and the surface separation profile, and considerably increases the minimum surface separation, which occurs on the exit of the bearing. The effect of the surface elastic deformation is shown to be obviously dependent on the fluid-bearing surface interaction.","PeriodicalId":511970,"journal":{"name":"Mechanics","volume":"24 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140435761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MechanicsPub Date : 2024-02-23DOI: 10.5755/j02.mech.34030
E. Benachour, Khadidja Asnoune, Mohammed Hasnat, B. Draoui
{"title":"Unsteady Numerical Investigation Strategy of Natural Convection in an Isosceles Superimposed Triangular Enclosure","authors":"E. Benachour, Khadidja Asnoune, Mohammed Hasnat, B. Draoui","doi":"10.5755/j02.mech.34030","DOIUrl":"https://doi.org/10.5755/j02.mech.34030","url":null,"abstract":"In energy applications, convection plays a dominant role in the transport of energy for the proper design in order to achieve higher heat transfer rates. Where the fluid motion is simply induced by density gradients. This study is concerned with transient natural convection in an isosceles-superimposed triangular enclosure. The inclination of the inclined partitions walls was θ =45°. Critical Rayleigh numbers have been obtained: Ra=106, especially for the fluid crushed between the two triangles where we can visualize the critical convection transaction between the air and water. The results in quantitative measurement of average Nusselt number change and qualitative visualization of streamline and isotherms are examined. The air and water streamlines and the temperature fields were obtained for the Rayleigh numbers 103 ≤ Ra ≤ 108 for both cases studied. Besides, the highest heat transfer performance is observed during the natural convection case of the water fluid, and the lowest heat is transferred when the fluid is dilatant. The triangular shape can greatly enhance the heat transfer from the bottom to the top at first in a smooth and harmonious manner, and then it turns into a more complex and disorderly shape when the water reaches high temperatures.","PeriodicalId":511970,"journal":{"name":"Mechanics","volume":"1 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139957549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}