Micro ECF (electro-conjugate fluid) hydraulic power sources based on the modular design of TPSEs (triangular prism and slit electrode pairs)

  • Joon-wan KimEmail author
  • Yoshiho Yamada
  • Shinichi Yokota


The paper presents a novel micro hydraulic power source by using the electro-conjugate fluid (ECF) jetting based on the modular design of a triangular prism and slit electrode pair (TPSE). ECF jetting is a phenomenon of electrohydrodynamics (EHD) related to the direct conversion of electrical energy into kinetic energy in the fluid. ECF is a functional fluid that can generate a strong and active jet flow between an anode and cathode in ECF, when a high DC voltage is applied. A micropump utilizing ECF jetting can work as a micro hydraulic power source for micro actuation, cooling, and propulsion in various fields. Since each field requires a different output pressure and flow rate, it is difficult to realize a general-purpose micropump to meet all objectives. Assuming that one anode and cathode pair in ECF generates the same output pressure and flow rate, an electrode pair was set as a module that is a TPSE in this paper, and a new approach to the modular design is proposed that satisfies the necessary output pressure and flow rate in each application by simply allocating TPSEs in series and parallel. Four different kinds of ECF micropumps, namely (a) ten TPSEs in series and no TPSE in parallel, (b) ten TPSEs in series and three TPSEs in parallel, (c) ten TPSEs in series and five TPSEs in parallel, and (d) ten TPSEs in series and three TPSEs in parallel separated by walls, were designed and fabricated by MEMS fabrication. The experimental results showed that output pressure was affected only by serialized TPSEs not parallelized ones, and the output flow rate was raised by using increasing numbers of TPSEs in parallel, verifying the versatility and effectiveness of the proposed modular design for realizing multi-purpose ECF hydraulic power sources.


Micro hydraulic power sources Electro-conjugate fluid (ECF) Micropump Modular design 



The authors thank Kazuya Edamura (New Technology Management Co., Ltd., 2-9-1-306 Higashishinkoiwa, Katsushika-ku, Tokyo 124-0023, Japan) for his support in providing the information concerning ECFs.

Funding information

A part of this work was supported by a JSPS KAKENHI Grant Number 18H01359.


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Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2019

Authors and Affiliations

  1. 1.Laboratory for Future Interdisciplinary Research of Science and Technology (FIRST), Institute of Innovative Research (IIR)Tokyo Institute of TechnologyYokohamaJapan
  2. 2.Department of Mechano-Micro Engineering, Interdisciplinary Graduate School of Science and EngineeringTokyo Institute of TechnologyYokohamaJapan
  3. 3.Precision and Intelligence LaboratoryTokyo Institute of TechnologyYokohamaJapan

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