The geometrical parameters of impeller or volute casing (including guide vane ofmultistage pump) have a great effect on pump characteristics, but ultimately. the pump characteris-tics are determined by the geometrical...The geometrical parameters of impeller or volute casing (including guide vane ofmultistage pump) have a great effect on pump characteristics, but ultimately. the pump characteris-tics are determined by the geometrical parameters of impeller and volute casing cooperatively. Inthis essay the effect of impeller and volute casing on pump characteristics will be studiedquantitatvely from the angle cf optimal matching of them.展开更多
Current studies of fan performance optimization mainly focus on two aspects： one is to improve the blade profile, and another is only to consider the influence of single impeller structural parameter on fan performan...Current studies of fan performance optimization mainly focus on two aspects： one is to improve the blade profile, and another is only to consider the influence of single impeller structural parameter on fan performance. However, there are few studies on the comprehensive effect of the key parameters such as blade number, exit stagger angle of blade and the impeller outlet width on the fan performance. The G4-73 backward centrifugal fan widely used in power plants is selected as the research object. Based on orthogonal design and BP neural network, a model for predicting the centrifugal fan performance parameters is established, and the maximum relative errors of the total pressure and efficiency are 0.974% and 0.333%, respectively. Multi-objective optimization of total pressure and efficiency of the fan is conducted with genetic algorithm, and the optimum combination of impeller structural parameters is proposed. The optimized parameters of blade number, exit stagger angle of blade and the impeller outlet width are seperately 14, 43.9~, and 21 cm. The experiments on centrifugal fan performance and noise are conducted before and after the installation of the new impeller The experimental results show that with the new impeller, the total pressure of fan increases significantly in total range of the flow rate, and the fan efficiency is improved when the relative flow is above 75%, also the high efficiency area is broadened. Additionally, in 65% -100% relative flow, the fan noise is reduced. Under the design operating condition, total pressure and efficiency of the fan are improved by 6.91% and 0.5%, respectively. This research sheds light on the considering of comprehensive effect of impeller structrual parameters on fan performance, and a new impeller can be designed to satisfy the engineering demand such as energy-saving, noise reduction or solving air pressure insufficiency for power plants.展开更多
文摘The geometrical parameters of impeller or volute casing (including guide vane ofmultistage pump) have a great effect on pump characteristics, but ultimately. the pump characteris-tics are determined by the geometrical parameters of impeller and volute casing cooperatively. Inthis essay the effect of impeller and volute casing on pump characteristics will be studiedquantitatvely from the angle cf optimal matching of them.
基金supported by Hebei Provincial Natural Science Foundation of China(Grant No.E2012502016)Fundamental Research Funds for the Central Universities,China(Grant No.12QN39)PhD Programs Foundation of Ministry of Education of China(Grant No.20110036110009)
文摘Current studies of fan performance optimization mainly focus on two aspects： one is to improve the blade profile, and another is only to consider the influence of single impeller structural parameter on fan performance. However, there are few studies on the comprehensive effect of the key parameters such as blade number, exit stagger angle of blade and the impeller outlet width on the fan performance. The G4-73 backward centrifugal fan widely used in power plants is selected as the research object. Based on orthogonal design and BP neural network, a model for predicting the centrifugal fan performance parameters is established, and the maximum relative errors of the total pressure and efficiency are 0.974% and 0.333%, respectively. Multi-objective optimization of total pressure and efficiency of the fan is conducted with genetic algorithm, and the optimum combination of impeller structural parameters is proposed. The optimized parameters of blade number, exit stagger angle of blade and the impeller outlet width are seperately 14, 43.9~, and 21 cm. The experiments on centrifugal fan performance and noise are conducted before and after the installation of the new impeller The experimental results show that with the new impeller, the total pressure of fan increases significantly in total range of the flow rate, and the fan efficiency is improved when the relative flow is above 75%, also the high efficiency area is broadened. Additionally, in 65% -100% relative flow, the fan noise is reduced. Under the design operating condition, total pressure and efficiency of the fan are improved by 6.91% and 0.5%, respectively. This research sheds light on the considering of comprehensive effect of impeller structrual parameters on fan performance, and a new impeller can be designed to satisfy the engineering demand such as energy-saving, noise reduction or solving air pressure insufficiency for power plants.
