权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Analysis of Electrohydrodynamic Effect and Development of New Fluid Devices

电流体动力学效应分析及新型流体装置开发

基本信息

批准号：
12555210
负责人：
OTSUBO Yasufumi
金额：
$ 7.17万
依托单位：
Chiba University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

On the application of high DC electric fields to some insulating oils, a fiuidjet with a velocity of about 1ms^<-1> is generatedfromthepositive electrode due to electrohydrodynamic(EHD) effect. In this process, the electric energy is directly converted to kinetic energy of the fluid. The purpose of this study is the analysis of jet flow and development of new fluid devices. The flow patterns of EHD jet is discussed in relation to the geometry of vessel, electrode arrangement, field strength, and fluid properties. The speed of jet flow at a given field strength increases with decreasing electric conductivity and viscosity of fluid This finding provides a formulation method of good working fluids. By controlling the direction and speed of jet flow, new fluid devies are designed such as dielectric fluid motors, inkjet nozzles, micropumps, and elerctrorheological(ER) devices. The fluid motors simply consist of electrodes, rotor, and working fluids. Since the magnetic fields are not required, the dielectric fluid motors have various kinds of advantages. For example, the motors by the use of flexible and light materials are possible and this can serve to construct soft micromachine. When subjected to high DC fields, the extra stresses across the interfaces are induced and the continuous evolution of free surface from the nozzle exit can take place. The inkjet units consisting of needle electrode and capillary are developed without piezoelectric transducers. The fluids which are sandwiched in electrodes with flocked fabrics show viscosity increase under electric fields. The ER effects are applicable to mechanical devices such as clutch and shock absorber because the local fluidity is actively controlled. The EHD jets are very attractive in application to new fluid devices.

在高压直流电场作用下，由于电流体动力学效应，在某些绝缘油中产生了一股速度约为1 ms ~（<-1>-1）的射流。在这个过程中，电能直接转化为流体的动能。本研究的目的是分析射流和开发新的流体装置。讨论了EHD射流的流型与容器几何形状、电极布置、场强和流体性质的关系。在一定场强下，射流速度随流体电导率和粘度的减小而增大。这一发现为优良工质的配制提供了一种方法。通过控制射流的方向和速度，可以设计出新的流体装置，如介质流体马达、喷墨喷嘴、微型泵和电流变装置等。流体马达简单地由电极、转子和工作流体组成。由于不需要磁场，介电流体马达具有各种优点。例如，通过使用柔性和轻质材料的电机是可能的，这可以用于构造软微机械。当受到高直流电场时，在界面上产生额外的应力，并且可以发生从喷嘴出口开始的自由表面的连续演化。研制了由针电极和毛细管组成的无压电传感器的喷墨单元。夹在植绒织物电极中的流体在电场作用下粘度增加。电流变效应适用于机械装置，如离合器和减震器，因为局部流动性是主动控制的。EHD射流在新型流体装置中具有很大的应用前景。