The model and analysis of the cantilever beam adhesion problem under the action of electrostatic force are given. Owing to the nonlinearity of electrostatic force, the analytical solution for this kind of problem is...The model and analysis of the cantilever beam adhesion problem under the action of electrostatic force are given. Owing to the nonlinearity of electrostatic force, the analytical solution for this kind of problem is not available. In this paper, a systematic method of generating polynomials which are the exact beam solutions of the loads with di?erent distributions is provided. The polynomials are used to approximate the beam displacement due to electrostatic force. The equilibrium equation o?ers an answer to how the beam deforms but no information about the unstuck length. The derivative of the functional with respect to the unstuck length o?ers such information. But to compute the functional it is necessary to know the beam deformation. So the problem is iteratively solved until the results are converged. Galerkin and Newton-Raphson methods are used to solve this nonlinear problem. The e?ects of dielectric layer thickness and electrostatic voltage on the cantilever beam stiction are studied. The method provided in this paper exhibits good convergence. For the adhesion problem of cantilever beam without electrostatic voltage, the analytical solution is available and is also exactly matched by the computational results given by the method presented in this paper.展开更多
This paper presents a new approach to evaluating the electrostatic/magnetic adhesion force between two adjacent objects separated by a thin gap.In this approach,instead of generating mesh for the gap,a contact boundar...This paper presents a new approach to evaluating the electrostatic/magnetic adhesion force between two adjacent objects separated by a thin gap.In this approach,instead of generating mesh for the gap,a contact boundary is introduced in the finite element modeling to obtain a reasonable field distribution;then the field in the gap is approximated based on the continuity condition at their interface,so that the adhesion force can be properly calculated.Moreover,a simple equivalent circuit model is introduced to explain how the thin gap influences the adhesion force significantly.Numerical experiments are given to demonstrate the validity of the proposed method and the significance of the thin gap.展开更多
In the process of aeroponics cultivation,the atomizer is one of the most important influencing factors on the cultivation process.This study presented the design of an ultrasonic atomization nozzle using contact charg...In the process of aeroponics cultivation,the atomizer is one of the most important influencing factors on the cultivation process.This study presented the design of an ultrasonic atomization nozzle using contact charging and a root droplet adhesion test rig.The purpose of this study was to reveal the relationship between the main operating parameters of the high-voltage electrostatic ultrasonic atomization nozzle and the atomization effect using droplet adhesion measurements.In this study,the ultrasonic effect of nozzle was achieved by using Laval tube,and the design of the key parameters for the high-voltage electrostatic ultrasonic atomization nozzle were inlet pressure,electrostatic voltage root core electrode material and spray distance;the droplet size variation and root adhesion patterns were obtained through experiments.The best operating parameters were analyzed by using the orthogonal test method,and the droplet deposition distribution of the root system at different scales was investigated in the atomization chamber.The test results revealed that when the root core electrode material was coppe and the nozzle working parameters were at 0.4 MPa of inlet pressure,at 1.75 m the spray distance,at 12 kV of the electrostatic voltage,the root system has the highest droplet adhesion.展开更多
Powder coating is an important process in the food industry,especially for snack foods such as potato chips,to create variety in food products.Electrostatic coating has been adopted in order to provide better transfer...Powder coating is an important process in the food industry,especially for snack foods such as potato chips,to create variety in food products.Electrostatic coating has been adopted in order to provide better transfer efficiency and lower the dust produced during coating.Studying the effect of electrode voltage on coating efficiency and evenness of baked potato chips using the developed electrostatic powder coating system was the main purpose of this research.Different types of NaCl(refined and table salts)were coated on baked potato chips at 0,30,40,50,60,and 70 kV.After coating with either refined or table salt,transfer efficiency,adhesion after coating,coating evenness and texture of samples were determined.Higher transfer efficiency,adhesion and coating evenness were observed when electrostatic coating was conducted at 30-50 kV.Most samples with higher transfer efficiency,adhesion and evenness were obtained after electrostatic coating.However,it did not significantly affect hardness of baked potato chips.展开更多
文摘The model and analysis of the cantilever beam adhesion problem under the action of electrostatic force are given. Owing to the nonlinearity of electrostatic force, the analytical solution for this kind of problem is not available. In this paper, a systematic method of generating polynomials which are the exact beam solutions of the loads with di?erent distributions is provided. The polynomials are used to approximate the beam displacement due to electrostatic force. The equilibrium equation o?ers an answer to how the beam deforms but no information about the unstuck length. The derivative of the functional with respect to the unstuck length o?ers such information. But to compute the functional it is necessary to know the beam deformation. So the problem is iteratively solved until the results are converged. Galerkin and Newton-Raphson methods are used to solve this nonlinear problem. The e?ects of dielectric layer thickness and electrostatic voltage on the cantilever beam stiction are studied. The method provided in this paper exhibits good convergence. For the adhesion problem of cantilever beam without electrostatic voltage, the analytical solution is available and is also exactly matched by the computational results given by the method presented in this paper.
基金National Natural Science Foundation of China(No.11272074)National Science and Technology Major Project(No.2011ZX02403-00)。
文摘This paper presents a new approach to evaluating the electrostatic/magnetic adhesion force between two adjacent objects separated by a thin gap.In this approach,instead of generating mesh for the gap,a contact boundary is introduced in the finite element modeling to obtain a reasonable field distribution;then the field in the gap is approximated based on the continuity condition at their interface,so that the adhesion force can be properly calculated.Moreover,a simple equivalent circuit model is introduced to explain how the thin gap influences the adhesion force significantly.Numerical experiments are given to demonstrate the validity of the proposed method and the significance of the thin gap.
基金financially supported by the National Natural Science Foundation of China Program(Grant No.51975255)Jiangsu Agriculture Science and Technology Innovation Fund(Grant No.CX(18)3048)the“Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions”(Grant No.37,(2014))。
文摘In the process of aeroponics cultivation,the atomizer is one of the most important influencing factors on the cultivation process.This study presented the design of an ultrasonic atomization nozzle using contact charging and a root droplet adhesion test rig.The purpose of this study was to reveal the relationship between the main operating parameters of the high-voltage electrostatic ultrasonic atomization nozzle and the atomization effect using droplet adhesion measurements.In this study,the ultrasonic effect of nozzle was achieved by using Laval tube,and the design of the key parameters for the high-voltage electrostatic ultrasonic atomization nozzle were inlet pressure,electrostatic voltage root core electrode material and spray distance;the droplet size variation and root adhesion patterns were obtained through experiments.The best operating parameters were analyzed by using the orthogonal test method,and the droplet deposition distribution of the root system at different scales was investigated in the atomization chamber.The test results revealed that when the root core electrode material was coppe and the nozzle working parameters were at 0.4 MPa of inlet pressure,at 1.75 m the spray distance,at 12 kV of the electrostatic voltage,the root system has the highest droplet adhesion.
基金supported by the National Natural Science Foundation of China(5117304321136006+5 种基金2123600321322607)the Special Projects for Nanotechnology of Shanghai(12nm0502700)the Basic Research Program of Shanghai(13JC1408100)the Key Scientific and Technological Program of Shanghai(14521100800)the Fundamental Research Funds for the Central Universities
基金This work was supported by a grant from Thailand Research Funding and Office of the Higher Education Commission,contract no.MRG6080261.
文摘Powder coating is an important process in the food industry,especially for snack foods such as potato chips,to create variety in food products.Electrostatic coating has been adopted in order to provide better transfer efficiency and lower the dust produced during coating.Studying the effect of electrode voltage on coating efficiency and evenness of baked potato chips using the developed electrostatic powder coating system was the main purpose of this research.Different types of NaCl(refined and table salts)were coated on baked potato chips at 0,30,40,50,60,and 70 kV.After coating with either refined or table salt,transfer efficiency,adhesion after coating,coating evenness and texture of samples were determined.Higher transfer efficiency,adhesion and coating evenness were observed when electrostatic coating was conducted at 30-50 kV.Most samples with higher transfer efficiency,adhesion and evenness were obtained after electrostatic coating.However,it did not significantly affect hardness of baked potato chips.
