Development of Micro Flow Systems utilizing Functional Fluids of non-Suspension Type

利用非悬浮型功能液开发微流系统

• 批准号: 07555062
• 负责人: NARUMI Takatsune
• 金额: $ 5.76万
• 依托单位: Niigata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07555062/
• 关键词: Functional Fluid; Liquid Crystal; Electrorheology; Electrorheological Effect; Mechanics of Micro Flow; 電気的不安定性

We have been trying the development of micro flow systems utilizing the molecular alignment or the electroconvection of the liquid crystal in electric fields for an application to the micro machine. Relating to a micro damper or a micro lubrication system, we have investigated the influence of the electric field strength and the frequency of AC electric fields on the electrorheological (ER) effects in the narrow gaps. The following results are obtained : (1) In the DC electric field, a larger ER effect is obtained in the case of a molecular alignment than of the electroconvection. In the AC electric field, the ER effect is caused with the molecular alignment and nearly the same ER effect as in the DC electric field is obtained. In the view point of the industrial application, it is considered that the flow under the AC electric field has an advantage in the stability of the ER effect for the micro damper and micro lubrication system. (2) A transient response in the ER effect is nearly the same as the optical response. (3) In the case of very narrow gap (<10 mum), ER effect is decreased with the wall effect. (4) Liquid crystal with a positive dielectric anisotropy is useful in this purpose.We have also examined a micro flow generator (micro pump) by controlling the electroconvection. The electric field is yielded from up-stream to down-stream between two electrode combs faced each other. We couldn't control the electronconvection enough but a weak flow is generated in this apparatus. So, it may be said that these results will be applied to a micro pump and a micro actuator development.It is shown the high applicability of the liquid crystal to the micro flow systems from above results. Now we are developing the another type flow systems utilizing the electroconvection of liquid crystal.

我们一直在尝试开发利用分子取向或液晶在电场中的电对流来应用于微型机械的微流动系统。针对微阻尼器或微润滑系统，研究了电场强度和交流电场频率对窄间隙电流变效应的影响。结果表明：(1)在直流电场作用下，分子取向的电流变效应大于电对流的电流变效应。在交流电场中，电流变效应是由于分子的排列而引起的，并且获得了与直流电场中几乎相同的电流变效应。从工业应用的角度出发，认为交流电场作用下的流动对微阻尼器和微润滑系统电流变效应的稳定性具有优势。(2)电流变效应中的瞬时响应与光学响应几乎相同。(3)在很窄的带隙(&lt；10um)情况下，电流变效应随壁效应减弱。(4)具有正介电各向异性的液晶在这方面是有用的。我们还研究了一种通过控制电对流的微流发生器(微泵)。电场是在两个相对的电极梳子之间从上游向下游产生的。我们不能很好地控制电子对流，但在这个装置中产生了弱气流。因此，可以说，这些结果将应用于微泵和微执行器的开发。从以上结果可以看出，液晶在微流控系统中具有很高的适用性。现在我们正在开发另一种类型的流动系统，利用液晶的电对流。

项目成果

H.Maeda, T.Narumi, et al.: "Electrorheological Effect of Liquid Crystals in Narrow Gaps (in Japanese)" 74th JSME Fall Annual Meeting. No.96-15. 111-112 (1996)

H.Maeda、T.Narumi 等人：“窄间隙液晶的电流变效应（日语）”第 74 届 JSME 秋季年会。

前田浩芳,鳴海敬倫,他3名: "狭い隙間での液晶のER特性" 第44回レオロジー討論回講演要旨集. 215-218 (1996)

Hiroyoshi Maeda、Takatomo Narumi 等 3 人：“窄间隙液晶的 ER 特性”第 44 届流变学研讨会摘要 215-218（1996 年）。

鳴海敬倫 他3名: "液晶の電気的不安定性現象を伴う微小すきま内の流動" 第8回「電磁力関連のダイナミクス」シンポジウム講演論文集. No 96-252. 367-368 (1996)

Takahiro Narumi等3人：“液晶中伴随电不稳定现象的小间隙流动”第8届“与电磁力相关的动力学”研讨会论文集第96-252号（1996年）。

前田浩芳・鳴海敬倫 他2名: "微小すきまにおける液晶のER効果" 日本機械学会第74期全国大会講演論文集. No96-15 III. 111-112 (1996)

Hiroyoshi Maeda、Takahiro Narumi 等 2 人：“微小间隙中液晶的 ER 效应”日本机械工程学会第 74 届全国会议论文集 No96-15 III。