EHD Pump Research Articles

Predictive modeling of flexible EHD pumps using Kolmogorov–Arnold Networks

We present a novel approach to predicting the pressure and flow rate of flexible electrohydrodynamic pumps using the Kolmogorov–Arnold Network. Inspired by the Kolmogorov–Arnold representation theorem, KAN replaces fixed activation functions with learnable spline-based activation functions, enabling it to approximate complex nonlinear functions more effectively than traditional models like Multi-Layer Perceptron and Random Forest. We evaluated KAN on a dataset of flexible EHD pump parameters and compared its performance against RF, and MLP models. KAN achieved superior predictive accuracy, with Mean Squared Errors of 12.186 and 0.012 for pressure and flow rate predictions, respectively. The symbolic formulas extracted from KAN provided insights into the nonlinear relationships between input parameters and pump performance. These findings demonstrate that KAN offers exceptional accuracy and interpretability, making it a promising alternative for predictive modeling in electrohydrodynamic pumping.

Pocketable and Smart Electrohydrodynamic Pump for Clothes.

Seamlessly fusing fashion and functionality can redefine wearable technology and enhance the quality of life. We propose a pocketable and smart electrohydrodynamic pump (PSEP) with self-sensing capability for wearable thermal controls. Overcoming the constraints of traditional liquid-cooled wearables, PSEP with dimensions of 10 × 2 × 1.05 cm and a weight of 10 g is sufficiently compact to fit into a shirt pocket, providing stylish and unobtrusive thermal control. Silent operation coupled with the unique self-sensing ability to monitor the flow rate ensures system reliability without cumbersome additional components. The significant contribution of our study is the formulation and validation of a theoretical model for self-sensing in EHD pumps, thereby introducing an innovative functionality to EHD pump technology. PSEP can deliver temperature changes of up to 3 °C, considerably improving personal comfort. Additionally, the PSEP system features an intuitive, smartphone-compatible interface for seamless wireless control and monitoring, enhancing user interaction and convenience. Furthermore, the ability to detect and notify users of flow blockages, achieved by self-sensing, ensures an efficient and long-term operation. Through its blend of compact design, intelligent functionality, and stylish integration into daily wear, PSEP reshapes the landscape of wearable thermal control technology and offers a promising avenue for enhancing personal comfort in daily life.

On the Development of Injection Cathode Electrodes for EHD Transducers

Purpose To study the possibility of changing cathode injection in a grid axisymmetric EHD transducer with planeparallel modified electrodes.Methods. An estimate of the influence of the edge effect of electrode grids on the surface conductivity in the periphery of the interelectrode gap was obtained by numerical simulation, and the optimal geometry of the electrode holders of the grid EHD transducer was determined. Using the method of numerical calculation in the software environment Agros 2D, as well as using the analysis of SEM scans and the method of estimating the form factor of structures, the parameters of local electric fields of the structures of the surfaces of wires of grid electrodes modified during laser scribing were obtained.Results. The results of the development of a grid system of electrodes for electrohydrodynamic converters with enhanced cathodic charge injection are presented. The influence of the edge effect on the operation of EHD transducers is analyzed. The possibility of improving the grid electrode system of a model EHD pump is described. The composition and shape of microand nanostructures after scribing on the FMark-20RL laser marking complex have been studied. A qualitative estimate of the local electric field strength on nanostructures obtained by laser scribing of brass grids with a characteristic radius of 50 nm is made, which indicates an increase in the cathode injection of negative charges in the EHD system. With a distance between the electrodes of 1.5 mm and a potential difference between the electrodes of 1.5 kV/cm, the magnitude of the local tension at the top of the nanostructure with a curvature radius of about 50 nm can reach 5.5⋅107 V/cm.Conclusion. Laser scribing in the form of concentric circles of brass grid electrodes makes it possible to intensify cathodic charge injection by amplifying local electric fields from microand nanostructures. The use of plexiglass dielectric holders can reduce surface leakage currents at the periphery of grid electrodes.

Development of artificial muscle system with EHD pump as a drive source

Development of artificial muscle system with EHD pump as a drive source

LED chip cooling system using ionic wind induced by multi-wire corona discharge

• A T-shaped multi-wire ionic wind pump is developed for cooling a high-power LED chip. • Relationship between air flow in the pump and its electrode configuration is revealed. • Increasing the wire-plate gap in the outlet channel strengthens the reverse discharge effect. • Arranging electrodes in the outlet channel further improves the performance of the T-shaped EHD pump. The high temperature of a light-emitting diode (LED) chip reduces its luminous output and lifetime and can even cause catastrophic damage to the chip. In recent years, ionic wind generators have shown great potential for LED chip cooling owing to their noiselessness, low energy consumption, and compact structure. However, the heat transfer and flow characteristics of ionic wind generated by multi-wire electrodes for LED cooling have not been sufficiently investigated. In this study, a T-shaped multi-wire ionic wind pump, in which each wire electrode corresponds to a pair of parallel plates, was designed for heat dissipation of a 24 W high-power LED chip. The relationship between the air flow characteristics inside the ionic wind pump and the electrode configuration was revealed through numerical simulations. Then, an optimized ionic wind pump was fabricated to test the cooling performance of the LED chip. The results show that each pair of plate electrodes has a critical length, and the average velocity at the pump inlet becomes independent of the plate length when it exceeds this critical value. For fixed wire electrodes in the outlet channel, when their operating voltage remains constant, increasing the wire-plate distance reduces the charge density around these wires, thus strengthening the reverse discharge effect and reducing the average velocity at the pump inlet. When only the wire in the inlet channel discharges electricity at a fixed voltage of 18 kV, the ionic wind pump can stabilize the LED case temperature below its safe temperature (LED operating voltage: 36 V). If all wires discharge electricity at a fixed voltage of 18 kV, the LED case temperature can be further reduced to 74 °C, which is lower than the maximum rated case temperature of 85 °C. In conclusion, when designing multi-wire ionic wind pumps, the electrodes inside them should be elaborately configured to reduce mutual interference and maximize the ionic wind flow rate. The designed ionic wind pump can serve as a noiseless thermal management equipment for high-power LED illumination devices.

EHD gas pump in a square channel with electrodes mounted on one wall

Gas pumping using corona wind generator in a square channel has been experimentally examined for three electrode configurations and two operating stages. For the proposed EHD pump, the emitting electrodes are flush mounted on one side of the channel walls so that the air flow produced is similar to that of a wall jet. Three electrode configurations (separately with 1, 3, and 7 emitting electrodes) are investigated for their effectiveness in sustaining and enhancing the volume flow rate as well as reducing the power requirement. Also investigated is the performance of the pump, a measure of the effectiveness in gas pumping, when it is operated in series. The results obtained are compared with those reported in the literature for EHD pumps with electrodes mounted all around the channel walls. It has been found that the performance of the proposed EHD pump is comparable to, if not better than, that of the previous ones while using fewer electrodes. Through the assessment of their performance, present results can provide important implications for practical applications of this technology.

Development of EHD pump based on numerical simulation of electric field

Development of EHD pump based on numerical simulation of electric field

Development of actuator for driving tail fin of fish type underwater exploration robot applying EHD pump

Development of actuator for driving tail fin of fish type underwater exploration robot applying EHD pump

Numerical analysis of electrostatic field in EHD pump

Numerical analysis of electrostatic field in EHD pump

Study on asymmetry of applied electric field in micro EHD pump

Study on asymmetry of applied electric field in micro EHD pump

백색 LED 제조를 위한 정전기력과 보이스코일모터를 이용한 디스펜서 시스템 개발

LED(Light Emitting Diode) is used in various filed like a display because of low power consuming, long life span, high brightness, rapid response time and environmental-friendly characteristic. General fabrication method is combination blue light LED chip with yellow fluorescent substance. Because this way is suitable for industry field in terms of convenience, economic, efficiency. In white light LED packaging process, encapsulation process that is dispensing fluorescent substance with silicon to blue light LED chip is most important. So, in this paper we develop EHD pump system using voice coil motor and electrostatic pump for dispensing fluorescent substance. For these things we conduct basic test about liquid surface profiles by voltage and process time. Through this data we decide optimal process condition and verify the optimal condition using design of experiment method. And to confirm uniformity of the condition, we conduct repeat dispensing test.

417 矩形断面平行電極群からなるEHDポンプの特性(GS 流体機器)

417 矩形断面平行電極群からなるEHDポンプの特性(GS 流体機器)

Conversion of energy under conditions of electroisothermal convection

The physical aspects of the conversion of electric energy into mechanical energy (an EHD pump) and mechanical energy into electric energy (an EHD generator) are described. Examples of the practical design of such converters are given: an EHD pump at an “electric wind” in a poor conducting liquid; an EHD wind generator; an EHD flowmeter generator; a Kelvin generator. The obtained results can be used as a basis for the development and design of working EHD energy converters.

329 EHDポンプによる振動流発生機構とその特性(T06-2 マイクロ・ナノ熟流体システム(2) マイクロフルイディクス,大会テーマセッション,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

A micro-electrohydrodynamics (EHD) pump to generate an oscillating flow is newly developed and experimentally tested. The EHD pump is the overall dimensions of 30 ×30×7.8 mm and has a pumping channel of 24×24×0.9 mm which is bend in parallel. In order to generate symmetric oscillating flow, alternate voltage was applied. Experimental results indicate that the newly developed pump is the twice as good as previous pump at static pressure and flow rate. A new model pump generated up to 550 Pa at an applied voltage of 1kV. New model pump generate higher static pressure and higher flow rate by the use DBS in place of DBE at working fluid. The amplitude of oscillating flow become smaller with decreasing the frequency.

Fundamental Characteristics of an EHD pump with Spherical Electrode

Fundamental Characteristics of an EHD pump with Spherical Electrode

Improvement for Pressure Performance of Micro-EHD Pump with an Arrangement of Thin Cylindrical Electrodes

A micro-electrohydrodynamic (EHD) pump is experimentally tested. In order to improve the static pressure performance, the EHD pump examined in this paper was fabricated with a series of thin stainless steel wires (the outer diameter is 0.3mm). The overall dimensions of the EHD pump were 30× 30×4.9mm and of the pumping channel were 24× 24× 0.9mm. An electrode pair consisted of one emitter electrode and two collector ones. The five sets of pumps were prepared for experiment. Those pumps were consisting of the number of electrode pairs from 1 to 5. The static pressure is measured with dibutyl-sebacate as a working fluid which has a dielectric constant, e / e 0=4.8 and a low electric conductivity, σ=4.7× 10-10S/m. The experimental results are compared with the theoretical results. In the theoretical model, the pressure is generated by Coulomb force which forces to move the unipolar ions in the high electric field. The experimental results indicate that the pressure increase as the number of electrode pairs increases and is generated up to 350Pa at an applied voltage of 1kV with 5 electrode pairs. Also, the experimental results show a good agreement with the theoretical ones. It is found that the theoretical model is useful for design of the high performance EHD pumps.

Distinctive flow properties of liquid jet generated by EHD pump and conical nozzle

AbstractThe electrohydrodynamic liquid jets induced by the mechanism which is referred to as pure conduction pumping were investigated in isothermal weakly conducting liquids, HFC43‐10 and HCFC123. The properties of the liquid jets (flow velocity, pumping pressure, and flow pattern) were examined by using grounded electrodes of four different types opposite a pseudo‐doughnut electrode under an applied DC voltage. These electrode systems gave rise to a powerful liquid jet, but in the working liquids used here, there was an effect of the voltage polarity on the flow direction. In order to create a more effective liquid jet with high directivity, a special nozzle (referred to as a conical nozzle in this paper) was used together with the electrode system. This nozzle can produce a distinctive pattern (spiral structure) of jets emerging from the outlet of the nozzle. In this paper, the spiral structure of the liquid jets has been analyzed using the basic equations of fluid mechanics. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 9–19, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20133

MICRO-ELECTROHYDRODYNAMIC PUMP BY DIELECTRIC FLUID: IMPROVEMENT FOR PERFORMANCE OF PRESSURE USING CYLINDRICAL ELECTRODES

This paper presents the improvements for the performance of a micro-electrohydrodynamic (EHD) pump and the fundamental model theory based on unipolar charge conduction. The EHD pump was fabricated with thin stainless wires which are the diameter of 0.3mm. An electrode pair consisted of one emitter electrode and two collector electrodes. The distance between the emitter and the collector electrode in an electrode pair had a 0.2mm. Static pressure tests have been performed with a dielectric fluid. In order to increase the pressure performance, the electrode pair was increased from one to five at the distance between the electrode pairs, 2.0mm. As a result, it is found that the increase of the electrode pairs improve the pressure performance. The EHD pump produces a static pressure about 700 Pa with five electrode pairs using Dibutyl Sebacate. Both experimental and theoretical pressure results show a liner relationship. This linear relationship confirmed the unipolar conduction concept theoretically.

Micro-Electrohydrodynamic Pump by Dielectric Fluid

A Micro-Electrohydrodynamic (EHD) pump is tested experimentally. The EHD pump examined in this paper is fabricated with two cylindrical copper electrodes of the inner diameter 3 mm. The distance between electrodes was changed from 0.6 mm to 1.2 mm. In order to simplify the characterization of the pressure capacity of the EHD pump, the uniform electric field added in the gap between the cylindrical electrodes using aluminum disc electrodes (40 mm outer diameter). The static pressure and the mean velocity in a closed fluidic circuit were measured with Dibutyl sebacate as working fluid. The liquid has a dielectric constant, e/e 0 = 4.8 and a low electric conductivity, σ=4.7× 10 -10 (S/m). The static pressure results are compared with the theoretical results. The theoretical model is based on the unipolar conduction which generates the space charge in the liquid. In this model, the Coulomb force can contribute to the EHD motion. The static pressure results show a linear relationship with the square of the electric filed. This linear relationship supports the assumption that the unipolar conduction generates the pressure driving force. The estimation of the EHD pump efficiency based on the theoretical model is 18% with the electrode gap of 1.2mm between the electrodes and 5% with the one of 0.6 mm.

エアーウエイブEHDポンプにおける液流の可視化計測

In this work, an AW (Air Wave) type EHD pump was examined, where the electrode system consists of a wire electrode in gas-phase and a partially immersed plate electrode inclined to the gas-liquid interface. This type of non-intrusive/non-moving component pump is normally used for the transport of hazardous liquid from containers or for the cleanup of spilled hazardous liquids. The EHD liquid pumping phenomenon was generated on the inclined plate electrode surface near the gas-liquid interface exposed to gas-phase corona discharges. The measurements of liquid flow towards the plate electrode surface were conducted by PIV. The fundamental characteristics of the two-phase EHD pump such as time-averaged liquid pumping flow rate, time-averaged current and internal liquid flow distribution for DC applied voltage were experimentally investigated in detail. The pumping performance was characterized by corona discharge induced dielectric EHD and conductive EHD, fluid viscous and gravity forces in terms of dimensionless parameters.