Mini centrifugal pumps having a diameter smaller than lOOmm are employed in many fields. But the design method for the mini centrifugal pump is not established because the internal flow condition for these small-sized...Mini centrifugal pumps having a diameter smaller than lOOmm are employed in many fields. But the design method for the mini centrifugal pump is not established because the internal flow condition for these small-sized fluid machines is not clarified and conventional theory is not suitable for small-sized pumps. Therefore, mini cen- trifugal pumps with simple structure were investigated by this research. Splitter blades were adopted in this re- search to improve the performance and the internal flow condition of mini centrifugal pump which had large blade outlet angle. The original impeller without the splitter blades and the impeller with the splitter blades were prepared for experiment. The performance tests are conducted with these rotors in order to investigate the effect of the splitter blades on performance and internal flow condition of mini centrifugal pump. On the other hand, a three dimensional unsteady numerical flow analysis was conducted to investigate the change of the internal flow according to the rotor rotation. It is clarified from the experimental results that the performance of the mini cen- trifugal pump is improved by the splitter blades. The blade-to-blade low velocity region was suppressed in the case with the splitter blades. In addition to that, the unsteady flows near the volute casing tongue were suppressed due to the splitter blades. In the present paper, the performance of the mini centrifugal pump is shown and the un- steady flow condition is clarified with the results of the numerical flow analysis. Furthermore, the effects of the splitter blades on the performance and the unsteady internal flow condition are investigated.展开更多
Particle Image Velocimetry (PIV) technology was used to study the unsteady internal flow in a double-blade centrifugal pump (DBCP) impeller at the design flow rate.Relative velocity distributions and turbulence intens...Particle Image Velocimetry (PIV) technology was used to study the unsteady internal flow in a double-blade centrifugal pump (DBCP) impeller at the design flow rate.Relative velocity distributions and turbulence intensity distributions in the DBCP impeller at six phase conditions were obtained.And mean dimensionless relative velocity,turbulence intensity,mean absolute flow angle,mean relative flow angle,mean dynamic pressure and mean angular momentum distributions at the different radii of impeller were calculated.Results show that from impeller inlet to impeller outlet,turbulence intensities gradually decrease.With the increase of radius r,mean dimensionless relative velocity first decreases and then increases,while variation tendencies of mean absolute flow angle and mean dynamic pressure are the opposite.With the increase of radius r,turbulence intensity and mean relative flow angle first decrease,then increase,and then decrease,while mean angular momentum gradually increases.展开更多
文摘Mini centrifugal pumps having a diameter smaller than lOOmm are employed in many fields. But the design method for the mini centrifugal pump is not established because the internal flow condition for these small-sized fluid machines is not clarified and conventional theory is not suitable for small-sized pumps. Therefore, mini cen- trifugal pumps with simple structure were investigated by this research. Splitter blades were adopted in this re- search to improve the performance and the internal flow condition of mini centrifugal pump which had large blade outlet angle. The original impeller without the splitter blades and the impeller with the splitter blades were prepared for experiment. The performance tests are conducted with these rotors in order to investigate the effect of the splitter blades on performance and internal flow condition of mini centrifugal pump. On the other hand, a three dimensional unsteady numerical flow analysis was conducted to investigate the change of the internal flow according to the rotor rotation. It is clarified from the experimental results that the performance of the mini cen- trifugal pump is improved by the splitter blades. The blade-to-blade low velocity region was suppressed in the case with the splitter blades. In addition to that, the unsteady flows near the volute casing tongue were suppressed due to the splitter blades. In the present paper, the performance of the mini centrifugal pump is shown and the un- steady flow condition is clarified with the results of the numerical flow analysis. Furthermore, the effects of the splitter blades on the performance and the unsteady internal flow condition are investigated.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51079062,51179075,51109095,51239005,and51209105)the National Science & Technology Pillar Program of China(Grant Nos. 2011BAF14B03 and 2013BAK06B02)+3 种基金the Natural ScienceFund of Jiangsu Province of China (Grant No. BY2011140)Science and Technology Support Program of Jiangsu Province of China (Grant Nos.BE2012129 and BE2012131)the Priority Academic Program Development of Jiangsu Higher Education Institutions and Senior Professional Scientific Research Project of Jiangsu University of China (Grant No.12JDG045)supported from the Priority Research Centers Program (2012-048078) through the National Research Foundation of the Republic of Korea
文摘Particle Image Velocimetry (PIV) technology was used to study the unsteady internal flow in a double-blade centrifugal pump (DBCP) impeller at the design flow rate.Relative velocity distributions and turbulence intensity distributions in the DBCP impeller at six phase conditions were obtained.And mean dimensionless relative velocity,turbulence intensity,mean absolute flow angle,mean relative flow angle,mean dynamic pressure and mean angular momentum distributions at the different radii of impeller were calculated.Results show that from impeller inlet to impeller outlet,turbulence intensities gradually decrease.With the increase of radius r,mean dimensionless relative velocity first decreases and then increases,while variation tendencies of mean absolute flow angle and mean dynamic pressure are the opposite.With the increase of radius r,turbulence intensity and mean relative flow angle first decrease,then increase,and then decrease,while mean angular momentum gradually increases.