In order to study the relationship between the important parameters of internal flow and the effect of drag and noise reduction,the internal flow field and sound field characteristics of bionic centrifugal pump are st...In order to study the relationship between the important parameters of internal flow and the effect of drag and noise reduction,the internal flow field and sound field characteristics of bionic centrifugal pump are studied in this paper.Based on the methods of theoretical analysis,numerical simulation and test,the relationship between wall average shear stress,drag reduction rate,increasing efficiency and noise reduction rate of internal sound field is studied.Internal flow parameters to judge and predict the effect of drag and noise reduction are revealed.The results show that the bionic pit can effectively increase the thickness of the boundary layer and reduce the Reynolds stress on the wall.The resistance on the wall is reduced and the hydraulic efficiency of the centrifugal pump is increased.The noise reduction rate is basically consistent with the changing trend of the drag reduction rate,increasing efficiency and wall average shear stress in the flow field.Wall average shear stress can reveal the effect of drag and noise reduction,so the effect of drag and noise reduction can be predicted and judged by the change of wall average shear stress.展开更多
Unlike most animals,plants fail to move bodily at will.However,movements also occur in every single part of plants out of energy and nutrients needs,spanning from milliseconds to hours on a time scale.And with the gro...Unlike most animals,plants fail to move bodily at will.However,movements also occur in every single part of plants out of energy and nutrients needs,spanning from milliseconds to hours on a time scale.And with the growing understanding of plant movement in the academic community,bionic soft robots based on plant movement principles are increasingly studied and are considered by scientists as a source of inspiration for innovative engineering solutions.In this paper,through the study of the biological morphology,microstructure,and motion mechanism of the flytrap,we developed chambered design rules,and designed and fabricated a gas-driven bionic flytrap blade,intending to investigate its feasibility of performing complex bending deformation.The experimental result shows that the bionic flytrap blade can achieve multi-dimensional bending deformation,and complete the bending and closing action within 2 s.The performance of the bionic flytrap blade fabricated is in high agreement with the real flytrap blade in terms of bending and deformation,achieving an excellent bionic design effect.In this study,the chambered design rules of the bionic flytrap blade were proposed and developed,and the possibility of its deformation was investigated.The effects of different chamber types and different flow channel design precepts on the bending deformation of the bionic flytrap blade were revealed,together with the relationship between the response time and flow rate of the bionic flytrap blade.At last,this study provides new ideas for the study of plant blade motion mechanism in a hope to expand the application fields of bionic robots,especially hope to offer solutions for plant-type robotics.展开更多
基金This work was supported by National Natural Science Foundation of China(Nos.51879122,51579117 and 51779106)National Key Research and Development Program of China(Nos.2016YFB0200901 and 2017YFC0804107)+4 种基金Zhenjiang key research and development plan(Nos.GY2017001and GY2018025)the Open Research Subject of Key Labo-ratory of Fluid and Power Machinery,Ministry of Education,Xihua University(Nos.szjj2017-094 and szijj2016-068)Sichuan Provincial Key Lab of Process Equipment and Control(Nos.GK201614 and GK201816)Jiangsu University Young Talent training Program-Outstanding Young backbone Teacher,Program Development of Jiangsu Higher Education Institutions(PAPD)Jiangsu top six talent summitproject(GDZB-017).
文摘In order to study the relationship between the important parameters of internal flow and the effect of drag and noise reduction,the internal flow field and sound field characteristics of bionic centrifugal pump are studied in this paper.Based on the methods of theoretical analysis,numerical simulation and test,the relationship between wall average shear stress,drag reduction rate,increasing efficiency and noise reduction rate of internal sound field is studied.Internal flow parameters to judge and predict the effect of drag and noise reduction are revealed.The results show that the bionic pit can effectively increase the thickness of the boundary layer and reduce the Reynolds stress on the wall.The resistance on the wall is reduced and the hydraulic efficiency of the centrifugal pump is increased.The noise reduction rate is basically consistent with the changing trend of the drag reduction rate,increasing efficiency and wall average shear stress in the flow field.Wall average shear stress can reveal the effect of drag and noise reduction,so the effect of drag and noise reduction can be predicted and judged by the change of wall average shear stress.
基金the National Natural Science Foundation of China,51905084the Natural Science Foundation of Heilongjiang Province,YQ2021E002.
文摘Unlike most animals,plants fail to move bodily at will.However,movements also occur in every single part of plants out of energy and nutrients needs,spanning from milliseconds to hours on a time scale.And with the growing understanding of plant movement in the academic community,bionic soft robots based on plant movement principles are increasingly studied and are considered by scientists as a source of inspiration for innovative engineering solutions.In this paper,through the study of the biological morphology,microstructure,and motion mechanism of the flytrap,we developed chambered design rules,and designed and fabricated a gas-driven bionic flytrap blade,intending to investigate its feasibility of performing complex bending deformation.The experimental result shows that the bionic flytrap blade can achieve multi-dimensional bending deformation,and complete the bending and closing action within 2 s.The performance of the bionic flytrap blade fabricated is in high agreement with the real flytrap blade in terms of bending and deformation,achieving an excellent bionic design effect.In this study,the chambered design rules of the bionic flytrap blade were proposed and developed,and the possibility of its deformation was investigated.The effects of different chamber types and different flow channel design precepts on the bending deformation of the bionic flytrap blade were revealed,together with the relationship between the response time and flow rate of the bionic flytrap blade.At last,this study provides new ideas for the study of plant blade motion mechanism in a hope to expand the application fields of bionic robots,especially hope to offer solutions for plant-type robotics.
