Optimization of High Flow Rate Nanoporous Electroosmotic Pump

2008 ◽  
Vol 130 (8) ◽  
Author(s):  
Y. Berrouche ◽  
Y. Avenas ◽  
C. Schaeffer ◽  
P. Wang ◽  
H.-C. Chang
Keyword(s):  
Flow Rate ◽  
Pore Radius ◽  
Debye Length ◽  
Maximum Flow ◽  
High Flow ◽  
Nanoporous Silica ◽  
Thermodynamic Efficiency ◽  
Hydraulic Circuit ◽  
Electroosmotic Pump ◽  
Disk Substrate

We present a theory for optimizing the thermodynamic efficiency of an electroosmotic (EO) pump with a large surface area highly charged nanoporous silica disk substrate. It was found that the optimum thermodynamic efficiency depends on the temperature, the silica zeta potential, the viscosity, the permittivity, the ion valency, the tortuosity of the nanoporous silica but mainly the effective normalized pore radius of the substrate scaled with respect to the Debye length. Using de-ionized water as the pumping liquid, the optimized EO pump generates a maximum flow rate of 13.6ml∕min at a pressure of 2kPa under an applied voltage of 150V. The power consumed by the pump is less than 0. 4W. The EO pump was designed to eliminate any bubble in the hydraulic circuit such that the pump can be operated continuously without significant degradation in the performance.

Thermodynamic Efficiency of Porous Glass Electroosmotic Pumps

2003 ◽  
Author(s):  
Shuhuai Yao ◽  
Shulin Zeng ◽  
Juan G. Santiago
Keyword(s):  
Zeta Potential ◽  
Flow Rate ◽  
Maximum Flow ◽  
Pump Current ◽  
Thermodynamic Efficiency ◽  
Two Phase ◽  
Poisson Boltzmann ◽  
Electroosmotic Pumps ◽  
Poisson Boltzmann Equation ◽  
Pump Pressure

This paper presents an analytical and experimental study of electroosmotic (EO) pumps designed to be integrated with two-phase microchannel heat exchangers with load capacities of order 100 W and greater. We have fabricated sintered glass EO pumps that provide maximum flow rates and pressure capacities 33 ml/min and 1.3 atm, respectively, at 100 V applied potentials. We have developed an analytical model to solve for electroosmotic flow rate, total pump current, and thermodynamic efficiency as a function of pump pressure load for these porous-structure EO pumps. The model uses a symmetric electrolyte approximation valid for the high zeta potential regime and numerically solves the Poisson-Boltzmann equation for charge distribution in the idealized pore geometry. The model also incorporates an approximate ionic-strength-dependent zeta potential formulation. The effects of pressure and flow rate on thermodynamic efficiency are also analyzed theoretically and compared to our measurements.

Simulation and Experimental Study of a Porous Electroosmotic Pump

2011 ◽  
Vol 483 ◽  
pp. 320-326 ◽  
Author(s):  
Zhou Ling ◽  
Tao Yang ◽  
Fan Chao Meng ◽  
Lin Yi ◽  
Xiang Xian Zhang
Keyword(s):  
Porous Media ◽  
Flow Rate ◽  
Pore Diameter ◽  
Maximum Flow ◽  
Joule Heat ◽  
Maximum Pressure ◽  
Electrical Field ◽  
Electroosmotic Pump ◽  
The Mathematical Model ◽  
Truncated Gaussian

Aiming at the coupling problems of electrical field and flow field in porous media microchannels, the mathematical model of electroosmotic(EO) flow is built. For a single microchannel, the influence of voltage on velocity and joule heat is analyzed by using CoventorWare. Numerical analysis shows that the velocity is proportional to the voltage and the joule heat is small and negligible. For the porous media, the flow rate is investigated by truncated Gaussian distribution of pore diameter. The electroosmotic microporous pump is fabricated, and the experimental results indicate that the maximum flow rate of porous media micropump is 16.89ml/min and the maximum pressure is 120.1kPa.

Design and Analysis of a Thin Film Permanent Magnet Actuated Micro Pump

2013 ◽  
Vol 7 (2) ◽  
pp. 196-204 ◽  
Author(s):  
Chao Zhi ◽  
◽  
Tadahiko Shinshi ◽  
Minoru Uehara ◽  
Keyword(s):  
Thin Film ◽  
Permanent Magnet ◽  
Flow Rate ◽  
Maximum Flow ◽  
High Flow ◽  
Deformation Analysis ◽  
Maximum Pressure ◽  
Large Deformation Analysis ◽  
Micro Pump ◽  
Displacement Measurements

In this paper we present the design, analysis and an experimental evaluation of a micro pump utilizing a 20 µm thick, 3 mm diameter Thin Film Permanent Magnet (TFPM). The pump includes an electromagnet that uses a magnetic closed circuit. The design of the electromagnet was optimized and was theoretically explained. A PolyDiMethylSiloxane (PDMS) diaphragm with a thickness of approximately 80 µm was used in the pump. The electromagnetic force on the diaphragmwas calculated using a finite elementmethod. Large deformation analysis was used to calculate the displacement of the diaphragm. The force and displacement measurements agreed well with those calculated by simulation. The performance of the fabricated pump was also evaluated. During pumping, the displacement of the diaphragm reached 500 µm, which is the same as the height of the chamber. Furthermore, because of the large displacement, the pump is bubble tolerant and self-priming. A maximum flow rate of 50 µL/min and a maximum pressure of 110 Pa were achieved. A square wave input signal was demonstrated to be more effective than a sinusoidal signal in generating a high flow rate.

Design of Wheel Lifting Hydraulic System for Amphibious Vehicle

2015 ◽  
Vol 730 ◽  
pp. 293-296
Author(s):  
Xiao Tong Li ◽  
Li Qin Xie ◽  
Hong Bing Wang ◽  
Fang Fang Zhai ◽  
Hong Wang ◽  
...  
Keyword(s):  
Working Conditions ◽  
Flow Rate ◽  
Hydraulic System ◽  
Maximum Flow ◽  
Maximum Flow Rate ◽  
Driving Safety ◽  
Hydraulic Circuit ◽  
System Load ◽  
Low Speed ◽  
Hydraulic Cylinders

In accordance to the drawback of amphibious vehicle's low speed in water, a new kind of folding mechanism based on double wishbone suspension is proposed. Referring to the working conditions of the wheel lifted mechanism, the hydraulic circuit, which provides with the functions of pressure limiting, locked and pressure retaining, is designed to ensure the accuracy of wheel lifted and the driving safety. The appropriate hydraulic cylinders, hydraulic components and auxiliary components are chosen due to the hydraulic system load and the maximum flow rate.

scholarly journals Description and Validation of a Novel Score (Flow Index) as a Clinical Indicator of the Level of Respiratory Support to Children on High Flow Nasal Cannula

2021 ◽  
Author(s):  
Sandeep Tripathi ◽  
Jeremy S. Mcgarvey ◽  
Nadia Shaikh ◽  
Logan J. Meixsell
Keyword(s):  
Flow Rate ◽  
Odds Ratio ◽  
Retrospective Chart Review ◽  
Maximum Flow ◽  
Weight Fraction ◽  
High Flow ◽  
Nasal Cannula ◽  
Respiratory Support ◽  
Flow Index ◽  
High Flow Nasal Cannula

AbstractThis study's objective was to describe and validate flow index (flow rate × FiO2/weight) as a method to report the degree of respiratory support by high flow nasal cannula (HFNC) in children. We conducted a retrospective chart review of children managed with HFNC from January 1, 2015 to December 31, 2019. Variables included in the flow index (weight, fraction of inspired oxygen [FiO2], flow rate) and outcomes (hospital and intensive care unit [ICU] length of stay [LOS], escalation to the ICU) were extracted from medical records. Max flow index was defined by the earliest timestamp when patients FiO2 × flow rate was maximum. Step-wise regression was used to determine the relationship between outcome (LOS and escalation to ICU) and flow index. Fifteen hundred thirty-seven patients met the study criteria. The median first and maximum flow indexes of the population were 24.1 and 38.1. Both first and maximum flow indexes showed a significant correlation with the LOS (r = 0.25 and 0.31, p < 0.001). Correlation for the index was stronger than that of the variables used to calculate them and remained significant after controlling for age, race, sex, and diagnoses. Mild, moderate, and severe categories of first and max flow index were derived using quartiles, and they showed significant age and diagnosis independent association with LOS. Patients with first flow index >20 and maximum flow index >59.5 had increased odds ratio of escalation to ICU (odds ratio: 2.39 and 8.08). The first flow index had a negative association with rapid response activation. Flow index is a valid measure for assessing the degree of respiratory support for children on HFNC.

scholarly journals Description and validation of a novel score (Flow Index) as a clinical indicator of the level of respiratory support to children on high flow nasal cannula.

2020 ◽  
Author(s):  
sandeep tripathi ◽  
Jeremy Mcgarvey ◽  
Nadia Shaikh ◽  
Logan Meixsell
Keyword(s):  
Length Of Stay ◽  
Flow Rate ◽  
Retrospective Chart Review ◽  
Maximum Flow ◽  
High Flow ◽  
Nasal Cannula ◽  
Respiratory Support ◽  
Flow Index ◽  
High Flow Nasal Cannula ◽  
Independent Association

Objective: Describe & validate flow index (FiO2×flow rate/weight) to report the degree of respiratory support to children on high flow nasal cannula (HFNC) Methods: Retrospective chart review. Children managed with HFNC from 01/01/15 to 12/31/19. Variables included in the flow index (weight, FiO2, flow rate) and outcomes (hospital and ICU length of stay [LOS], escalation to the ICU) extracted from medical records. Max flow index defined by the earliest timestamp when patients FiO2×Flow rate was maximum. Step-wise regression used to determine the relationship between outcome (length of stay and escalation to ICU) and flow index Results: 1537 patients met the study criteria. Median 1st and maximum flow index of the population 24.1 and 38.1, respectively. Both 1st and maximum flow indexes showed a significant correlation with the LOS (r 0.25 and 0.31). Correlation for the index was stronger than that of the variables used to calculate them and remained significant after controlling for age, race, sex, and diagnoses. Mild, moderate, and severe categories of 1st and max flow index derived using quartiles and showed significant age and diagnosis independent association with LOS. Patients with 1st flow index >20 and maximum flow index >59.5 had increased odds ratio of escalation to ICU (OR 2.39 and 8.08). The 1st flow index had a negative association with rapid response activation. Conclusions: Flow index is a valid measure for assessing the degree of respiratory support for children on HFNC. High flow index associated with longer hospital LOS and the risk of escalation to ICU.

Thermal Performance of High-Flow Single-Phase Liquid-Cooled Heat Sinks

2012 ◽  
Author(s):  
Ildar F. Akhmadullin ◽  
Randall D. Manteufel ◽  
Christopher Greene
Keyword(s):  
Thermal Resistance ◽  
Flow Rate ◽  
Heat Sink ◽  
Heat Removal ◽  
Internal Flow ◽  
Maximum Flow ◽  
High Flow ◽  
Repeated Measurements ◽  
Heat Sinks ◽  
Flow Rates

Experimental measurements are reported for high-flow liquid-cooled heat sinks designed for cooling electronics components such as a CPU. The flow rate is up to 2 GPM with internal flow passage length scales on the order of 0.1 to 1.0 mm in the primary heat transfer region. Of the designs tested, three achieved maximum flow rates with pressure drops of less than 1.5 psi. Two have lower maximum flow rates because of higher internal flow resistance. In the experiments, particular attention is given to sources of experimental uncertainty and the propagation of uncertainty through the calculations to reported thermal resistance, R (°C/W). Analysis includes bias and precision errors for direct measurement of temperature, flow rate, and pressure drop. Additionally, a separate thermocouple calibration test is reported to establish measurement uncertainties for the system. Main emphasis is made to the error propagation in thermal resistance calculations of each heat sink and measurement of heat removal rate from the CPU. Data is used to determine the standard error for R which ranges up to about 0.05 °C/W with the maximum for one heat sink up to 0.07 °C/W. Averaging of repeated measurements at the same flow rate without accounting for the range of the original data will result in lower uncertainties in the reported results.

EXPERIMENTAL STUDY ON BASIC PERFORMANCE OF ELECTROOSMOTIC PUMP WITH ION EXCHANGING POROUS GLASS SLIT

2010 ◽  
Vol 24 (15n16) ◽  
pp. 2627-2632 ◽  
Author(s):  
HO LEE ◽  
GYU MAN KIM ◽  
CHOON YOUNG LEE ◽  
CHEOL WOO PARK ◽  
DAE JOONG KIM
Keyword(s):  
Drug Delivery ◽  
Experimental Study ◽  
Flow Rate ◽  
Maximum Flow ◽  
Precise Control ◽  
Electroosmotic Pump ◽  
Optimal Drug ◽  
Basic Performance ◽  
Electroosmotic Pumping ◽  
Performance Results

The basic concept and preliminary performance results of a miniaturized electroosmotic pump with diaphragms were included in the present study. The separation of an electroosmotic pumping liquid from a drug using diaphragms is mainly to have a freedom in choosing an electroosmotic pumping liquid and to achieve the optimal drug delivery with its preferable precise control. As a result, the maximum flow rate and current increased linearly according to the increment of applied voltage that is electric potential.

Design of the Cascaded Open-Channel Direct Current Electroosmotic Pump

2011 ◽  
Vol 483 ◽  
pp. 259-263 ◽  
Author(s):  
Ting Ting Liu ◽  
Zhu Chuan Bai ◽  
Yang Gao
Keyword(s):  
High Pressure ◽  
Flow Rate ◽  
Direct Current ◽  
Open Channel ◽  
Cooling System ◽  
Test System ◽  
High Flow ◽  
High Flow Rate ◽  
Driving Voltage ◽  
Electroosmotic Pump

Electroosmotic pump does not need moving mechanical parts, which can be fabricated by micromachining process and integrated with other micro-devices. Electroosmotic pump is the hydraulic actuator component and can be used in HPLC (High Pressure Liquid Chromatography), μTAS (Micro totally analysis system), chip test system, micro cooling system and micro drug delivery system, etc. The paper is to design an electroosmotic pump with low driving voltage, high pressure and high flow rate, and fabricate the samples of cascaded open-channel direct current electroosmotic pump. The three-dimensional model of one-stage parallel open-channel electroosmotic pump is established by finite element analysis software of CoventorWare. The numerical simulation of the electroosmotic pump performance has been done by CoventorWare. Compared with the equivalent circuit model, the results show that the cascaded open-channel direct current electroosmotic pump has the advantages of high flow rate and high pressure.

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