Improving the suction performance of centrifugal pumps by using jetting device is presented. The theoretical analysis, experimental study and engineering implementation show that suction performance of centrifugal pum...Improving the suction performance of centrifugal pumps by using jetting device is presented. The theoretical analysis, experimental study and engineering implementation show that suction performance of centrifugal pump can be improved with jetting device and be used for delivering the liquid media requiring high suction performance, whereas the efficiency and head of the pump will decrease a little. The effect of feed-back jetting on suction performance is the most obvious at design point. The suitable rate of feed-back flow is 2%-5%.展开更多
In this study,a jet cavitation device aimed at producing two-dimensional nanosheets was designed.The effects of cavitation generator type and jet pressure on the cavitation inception and intensity were examined by mon...In this study,a jet cavitation device aimed at producing two-dimensional nanosheets was designed.The effects of cavitation generator type and jet pressure on the cavitation inception and intensity were examined by monitoring the changes of sound pressure level(SPL).As such,the optimized cavitation generator with the best cavitation capability under the same ambient condition was determined.Further,BN and MoS 2,two kinds of layered materials,were exfoliated into individual flakes in aqueous solutions by this jet cavitation device.By investigating the morphology of these exfoliated flakes via scanning electron microscopy and transmission electron microscope,it was found that these pristine materials were mostly exfoliated into two-dimensional nanosheets,among which even monolayers were generally presented.This exfoliation process happened mainly due to the cavitation-induced intensive tensile stress acting on the layered materials.As graphene has been produced by this device successfully,it is anticipated that this jet cavitation device is suitable for producing other various two-dimensional nanosheets.展开更多
文摘Improving the suction performance of centrifugal pumps by using jetting device is presented. The theoretical analysis, experimental study and engineering implementation show that suction performance of centrifugal pump can be improved with jetting device and be used for delivering the liquid media requiring high suction performance, whereas the efficiency and head of the pump will decrease a little. The effect of feed-back jetting on suction performance is the most obvious at design point. The suitable rate of feed-back flow is 2%-5%.
基金supported by the Special Financial Support of Joint Building Project of the Beijing Education Committee
文摘In this study,a jet cavitation device aimed at producing two-dimensional nanosheets was designed.The effects of cavitation generator type and jet pressure on the cavitation inception and intensity were examined by monitoring the changes of sound pressure level(SPL).As such,the optimized cavitation generator with the best cavitation capability under the same ambient condition was determined.Further,BN and MoS 2,two kinds of layered materials,were exfoliated into individual flakes in aqueous solutions by this jet cavitation device.By investigating the morphology of these exfoliated flakes via scanning electron microscopy and transmission electron microscope,it was found that these pristine materials were mostly exfoliated into two-dimensional nanosheets,among which even monolayers were generally presented.This exfoliation process happened mainly due to the cavitation-induced intensive tensile stress acting on the layered materials.As graphene has been produced by this device successfully,it is anticipated that this jet cavitation device is suitable for producing other various two-dimensional nanosheets.
