An exact solution of laminar heat transfer problem for a uniform flow perpendicular to a rotating disk was obtained. Radial velocity at the outer edge of the boundary layer increases linearly in the radial direction, ...An exact solution of laminar heat transfer problem for a uniform flow perpendicular to a rotating disk was obtained. Radial velocity at the outer edge of the boundary layer increases linearly in the radial direction, while the temperature difference between the disk and outer flow follows a power law. The problem is solved using self-similar velocity and temperature profiles. Nusselt numbers were computed for the Prandtl numbers Pr=1 and 0.71 at different values of parameters affecting flow and heat transfer. Special flow regime was identified where rotating disk heat transfer is determined only by peculiarities of the impinging flow. Results of predictions agree well with known experiments in the vicinity of the stagnation point.展开更多
This study numerically analyzed the heat transfer characteristics outside the condenser of a rotating heat pipe grinding wheel(RHP-GW).The goal of this investigation is to determine the optimal structure and parameter...This study numerically analyzed the heat transfer characteristics outside the condenser of a rotating heat pipe grinding wheel(RHP-GW).The goal of this investigation is to determine the optimal structure and parameters for the condenser section of RHP-GW.Different fin height(f=0-7 mm),rotational Reynolds number(Rer=1602-6408)and jet Reynolds number(Rej=42379-108302)were analyzed under input heat flux of 4000 W/m2.A fully developed flow was imposed at the outlet of the nozzles.Results showed that the optimal heat transfer rate was obtained for fin height of 5 mm,which improved the average Nusselt number by 84%compared to the structure without fins.A critical Rej for each Rer that the impinging jet can reach the condenser section was found.The critical Rej value increases with Rer,which is in the range from 42379 to 61215 and 61215 to 80050 for Rer=6408 and Rer=9610,respectively.展开更多
The test apparatus used for investigating erosion-corrosion in aqueous media, including the pipe flow loop, impinging jet, rotating disk and rotating cylinder rigs is reviewed. With combining the impinging jet rig and...The test apparatus used for investigating erosion-corrosion in aqueous media, including the pipe flow loop, impinging jet, rotating disk and rotating cylinder rigs is reviewed. With combining the impinging jet rig and rotating cylinder electrode rig, the hydrodynamic characteristics of both rigs are analysed.展开更多
文摘An exact solution of laminar heat transfer problem for a uniform flow perpendicular to a rotating disk was obtained. Radial velocity at the outer edge of the boundary layer increases linearly in the radial direction, while the temperature difference between the disk and outer flow follows a power law. The problem is solved using self-similar velocity and temperature profiles. Nusselt numbers were computed for the Prandtl numbers Pr=1 and 0.71 at different values of parameters affecting flow and heat transfer. Special flow regime was identified where rotating disk heat transfer is determined only by peculiarities of the impinging flow. Results of predictions agree well with known experiments in the vicinity of the stagnation point.
基金This work was supported by the Natural Science Foundation of Jiangsu Province(Grant No.BK20190752)the National Natural Science Foundation of China(Grant No.51905275)+2 种基金the Natural Science Foundation of Colleges and Universities in Jiangsu Province(Grant No.19KJB460020)the Faculty Research Funding of Nanjing Forestry University(Grant No.163040111)the Open Foundation of Jiangsu Wind Power Generation Engineering and Technology Center(No.Zk19-03-12).
文摘This study numerically analyzed the heat transfer characteristics outside the condenser of a rotating heat pipe grinding wheel(RHP-GW).The goal of this investigation is to determine the optimal structure and parameters for the condenser section of RHP-GW.Different fin height(f=0-7 mm),rotational Reynolds number(Rer=1602-6408)and jet Reynolds number(Rej=42379-108302)were analyzed under input heat flux of 4000 W/m2.A fully developed flow was imposed at the outlet of the nozzles.Results showed that the optimal heat transfer rate was obtained for fin height of 5 mm,which improved the average Nusselt number by 84%compared to the structure without fins.A critical Rej for each Rer that the impinging jet can reach the condenser section was found.The critical Rej value increases with Rer,which is in the range from 42379 to 61215 and 61215 to 80050 for Rer=6408 and Rer=9610,respectively.
文摘The test apparatus used for investigating erosion-corrosion in aqueous media, including the pipe flow loop, impinging jet, rotating disk and rotating cylinder rigs is reviewed. With combining the impinging jet rig and rotating cylinder electrode rig, the hydrodynamic characteristics of both rigs are analysed.