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micropumping
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Modeling of a Thermopneumatic Micropump
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan (Supervisor) ; Saeedi, Mohammad Saeed (Supervisor) ; Shafii, Mohammad Behshad (Supervisor)
Abstract
Thermopneumatic micropump is one type of positive displacement micropumps, which has many applications due to its relatively large stroke volume, low working voltage, and simple fabrication in microscale. In this paper, a numerical study of heat transfer and fluid flow in a valveless thermopneumatically driven micropump is presented. For rectifying the bidirectional flow, a nozzle and a diffuser are used as the inlet and outlet of the chamber. Since the fluid flow is induced by the motion of a diaphragm, the numerical simulation includes fluid structure interaction, which requires applying a dynamic mesh. The domain of solution is divided into two sections; the actuator unit, which contains...
Fabrication and Theoretical Investigation of a Single Bubble Nozzle-Diffuser Micropump
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan (Supervisor) ; Saeedi, Mohammad Saeed (Supervisor)
Abstract
The potential of phase change process in liquids at microscale has been a favorite for the scientists to fabricate this type of micropumps. To hold unidirectional flow in microchannels usually nozzle-diffuser arrangement is used. Due to the existence of difference in pressure drop in the nozzle and diffuser sections, one can see unidirectional flow through diffuser direction. The objective of this article is to analyze analytically the thermo-hydrodynamic behavior of the Isopropyl Alcohol (IPA) bubble of a phase change micropump. Considering the simultaneous effects of hydrodynamic and thermal characteristics of the bubble in the bubble generation chamber, and temperature-saturation...
Fabrication and Experimental Investigation of Rotary Agnetohydrodynamic Micropump
, M.Sc. Thesis Sharif University of Technology ; Behshad Shafii, Mohammad (Supervisor)
Abstract
Considering the advantages and disadvantages of reported micropumps, we aimed to introduce a novel idea to diminish the disadvantages and promote the advantages of Magnetohydrodynamic (MHD) micropumps. This novel idea operates based on a mercury slug rotation in a circular microchannel. This cyclic motion of the mercury slug which is similar to a piston, push the fluid in the microchannel and pump the flow. However, to bring this idea into the practice, it must be integrated with a specific valve. Fluid has not to go through this specific valve. In contrary, mercury slug has to pass across this valve. These two specifications must be considered during the design process of the valve. On the...
Fabrication of Ferrofluidic Micropump
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor) ; Saidi, Mohammad Said (Supervisor) ; Saidi, Mohammad Hassan (Supervisor)
Abstract
In this project, two Ferrofluidic micropumps that do not need any mechanical moving parts are presented. These micropumps are including simple microchannels containing magnetic fluid plugs that are used as flow actuator and the on/off valve. Using external magnetic field actuation in this type of micropumps, the magnetic fluid would have continuous motion in a channel with micrometer dimensions that would provide the main fluid to be pumped. Although the plug of magnetic fluid has surface contact with operative fluid, but considering its specific features, it would not compine with the pumping fluid. These micropumps may be used to pump the fluids or gases. The outcomes of the investigation...
Design and Fabrication of a Novel Mercury Micropump Actuated Electeromagneticaly
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor)
Abstract
Considering the advantages and disadvantages of reported micropumps, we aimed to introduce a novel idea to diminish the disadvantages and promote the advantages of PiezoElectric micropumps. This novel idea operates based on a mercury slug actuation in a microchannel. This cyclic motion of the mercury slug which is similar to a piston, push the fluid in the microchannel and pump the flow. However, to bring this idea into the practice, a control system must be designed. This system contains: LABVIEW code, DAQ board & a switching Board. The pattern of actuating mercury is drawn in LABVIEW. DAQ Board produces electrical signals according to LABVIEW code. Switching board will transform the...
Numerical Simulation of Rotary Magnetohydrodynamic Micropump
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor)
Abstract
First by reviewing some built micropumps, the importance of rotary magnetohydrodynamic micropump has been highlighted. Then some information about the performance and rules applied to these specific micropumps has been provided. Based on the research, the necessity of using transient flow relations for analyzing the procedure of these micropumps would become crucial. The next step would be extracting the information out of dimensionlessrelations of magnetohydrodynamic theory and dimension less equations of momentum in transientsingle-phase fluid flow which is moved by theoverall Lorentzforce in between 2 parallel surfaces. It would be done in two state of using constantcurrent source and...
Numerical Simulation of Magneto Mercury Reciprocating Micropump
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor)
Abstract
In this investigation Magneto Mercury Reciprocating Micrpump (MMRM) the combination of Magneto-Hydrodynamic and Reciprocating micropumps has been analyzed. To achieve the analytical and numerical solution of one-tank and three-tank MMRM, the momentum, continuity, volume fraction and magnetohydrodynamic equations have been presented. The dimensionless analytical solution of one-phase and two-phase three dimensional MHD flow in the condition of using constant current and potential electrical source, has been offered.
The boundary between mercury and air has been tracked via VOF method in OpenFOAM software. VOF equation has been solved by explicit method with variable time step and maximum...
The boundary between mercury and air has been tracked via VOF method in OpenFOAM software. VOF equation has been solved by explicit method with variable time step and maximum...
Design and Fabrication of Reciprocating Micropumps with Actuated Fluid Slug
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor)
Abstract
Design, fabrication and performance of the reciprocating micropumps with actuated fluid slug have been investigated. In these micropumps, pumping principle is based on reciprocating movement of a fluid slug. The fluid slug must be conductive in magnetohydrodaynamic micropump to be actuated by Lorentz force and have good magnetic properties in ferrofluidic micropumps to be actuated by an external magnetic field.
On the other hand, a theory is developed in ahead of design and fabrication process to diagnose the critical and the most influential parameters. Magnetohydrodynamic micropumps in 4 distinict design using nozzle-diffuser element, passive ball valve and active mercury valve have...
On the other hand, a theory is developed in ahead of design and fabrication process to diagnose the critical and the most influential parameters. Magnetohydrodynamic micropumps in 4 distinict design using nozzle-diffuser element, passive ball valve and active mercury valve have...
Experimental Study of Movement of Mercury Droplets in Micro Channel by Electromagnetic Force
, M.Sc. Thesis Sharif University of Technology ; Afshin, Hossein (Supervisor)
Abstract
As today's tremendous advance occurred in biotechnology and nanotechnology, the microfluidic devices made a new success that was not possible with the traditional equipments. It was useful in such a way that by using a microliter volume of that fluid, we could have the ability to use it in biologics, medicine, aerospace, cooling electronic systems and medical discovery. One of the main component of fluidic microsystems are micropumps in which they divide into two types. Reciprocating micropumps have been worked by stimulating electromagnetic micropumps which is based on Lorentz law. In this project, we try to investigate the impact of effective parameters in the movement of the mercury mass....
Design and Fabrication of a Ferrofluidic Miniature Pump
, Ph.D. Dissertation Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor) ; Moosavi, Ali (Supervisor)
Abstract
This thesis presents the prototype design and fabrication of magnetically actuated miniature pumps which utilize self-sealing capability of ferrofluid-covered permanent magnets in both pumping and valving mechanisms. The contactless external actuation feature of the design enables integration of the pump with other PMMA-based microfluidic systems with low cost and disposability. The body of the 1st fabricated prototype pump consists of three nozzle/diffuser elements and two pumping chambers connected to the ends of a flat-wall pumping cylinder. A cylindrical permanent magnet placed inside the pumping cylinder acts as a piston which reciprocates by using an external magnetic actuator driven...
Design and Simulation of an Electrowetting Micro-Pump
,
M.Sc. Thesis
Sharif University of Technology
;
Javadi, Khodayar
(Supervisor)
Abstract
Micropumps are one of the most important devices in the field of microfluidics which have many applications in various fields of engineering. Electrostatic excitation is one of the types of excitation mechanisms in micropumps that is widely used in microelectromechanical systems due to its low power consumption and easier control. In this research, first, the physics of droplets on the surface studied, important dimensionless numbers and other factors influencing microfluidic phenomena are investigated. The effective parameters of the droplet motion and the mechanism of this motion are described. Besides, the phenomenon of electrowetting, one of the phenomena in the field of dynamics of...
Design and Making of Piezoelectric-based Micro-airpump for Flow Control Application
, M.Sc. Thesis Sharif University of Technology ; Ebrahimi, Abbas (Supervisor)
Abstract
The importance of creating a fluid flow with accurate and controllable flow in many industries is undeniable. There are several ways to create this type of flow, and a variety of pumps can be used to create such a flow. The presence of noise, limitations in reducing the flow rate (sometimes in some pumps the flow rate can not be reduced to a minimum), depreciation costs and many other limitations, reduce the attractiveness of using conventional pumps in some applications. The subject of this project is the design and construction of piezoelectric based micro-pumps to solve the above problems. In many applications, the need for fluid flow with very low flow and high quality and accuracy is...
Design of a Microfluidic System for Continuous Glucose Measurement, as well as Fabricating and Experimentally Testing the Biosensor
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Kazemzadeh Hannani, Siamak (Supervisor) ; Shahrokhian, Saeed (Co-Supervisor)
Abstract
Diabetic patients, unlike other people whose blood glucose vary in a limited and normal range, encounter hyperglycemia and hypoglycemia, so their glucose level should be measured periodically and kept in the normal range. The aim of this research is to design an implantable integrated microfluidic system in order to regularly measure the glucose level in the human body, using the microdialysis method. The main compartments of this system are a micropump, array of hollow microneedles at the base of them located semipermeable membranes, the channels of dialysis fluid and an electrochemical sensor for measuring the glucose level. The micropump of this system is designed and simulated based on...
Study on Motion of Electrical Conductor Fluid Plug Actuated Electromagnetically in Microsystems
, Ph.D. Dissertation Sharif University of Technology ; Shafii, Mohmmad Behshad (Supervisor) ; Afshin, Hossein (Supervisor)
Abstract
Micropumps are regarded as one of the devices used in microsystems, which are responsible for pumping working fluid. The Mercury Magneto Reciprocating (MMR) micropump, which has been introduced for less than a decade, is an innovative kind of micropumps which the pumping agent includes three liquid metal droplets (LMD) placed inside lateral chambers and reciprocated by the electromagnetic force inside the chambers. The working fluid located inside the main channel is pumped through due to the movement of these three LMDs. The equations governing this micropump are complex and their numerical solution is a time-consuming process, due to electromagnetic, hydrodynamic, and unsteady effects. The...
Numerical optimization of three-cavity magneto mercury reciprocating (MMR) micropump
, Article Engineering Applications of Computational Fluid Mechanics ; Volume 15, Issue 1 , 2021 , Pages 1954-1966 ; 19942060 (ISSN) ; Mofakham, A. A ; Shafii, M. B ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
The operation of the three-cavity magneto mercury reciprocating (MMR) micropump, whose prototype were presented in an earlier companion paper, was numerically explored. In the three-cavity MMR micropump, three mercury slugs are moved by a periodic Lorentz force with a phase difference in three separate cavities. A consecutive motion of the slugs in their cavities transfer air from the inlet to the outlet. Two-dimensional OpenFOAM simulations were carried out to explore the influence of electric current excitation phase difference and back-pressure. The numerical simulations predicted the MMR micropump (with no valve) with a phase difference of (Formula presented.) and (Formula presented.)...
A novel reciprocating micropump based on Lorentz force
, Article Progress in Biomedical Optics and Imaging - Proceedings of SPIE, 7 February 2015 through 9 February 2015 ; Volume 9320 , 2015 ; 16057422 (ISSN) ; 9781628414103 (ISBN) ; Hakimsima, A ; Shafii, M. B ; Sharif University of Technology
SPIE
2015
Abstract
Lorentz force is the pumping basis of many electromagnetic micropumps used in lab-on-a-chip. In this paper a novel reciprocating single-chamber micropump is proposed, in which the actuation technique is based on Lorentz force acting on an array of microwires attached on a membrane surface. An alternating current is applied through the microwires in the presence of a magnetic field. The resultant force causes the membrane to oscillate and pushes the fluid to flow through microchannel using a ball-valve. The pump chamber (3 mm depth) was fabricated on a Polymethylmethacrylate (PMMA) substrate using laser engraving technique. The chamber was covered by a 60 μm thick hyper-elastic latex rubber...
Theoretical and experimental studies of a magnetically actuated valveless micropump
, Article Journal of Micromechanics and Microengineering ; Volume 27, Issue 1 , 2017 ; 09601317 (ISSN) ; Shafii, M. B ; Moosavi, A ; Sharif University of Technology
Institute of Physics Publishing
2017
Abstract
This paper presents the prototype design, fabrication, and characterization of a magnetically actuated micropump. The pump body consists of three nozzle/diffuser elements and two pumping chambers connected to the ends of a flat-wall pumping cylinder. A cylindrical permanent magnet placed inside the pumping cylinder acts as a piston which reciprocates by using an external magnetic actuator driven by a motor. The magnetic piston is covered by a ferrofluid to provide self-sealing capability. A prototype composed of three bonded layers of polymethyl-methacrylate (PMMA) has been fabricated. Water has been successfully pumped at pressures of up to 750 Pa and flow rates of up to 700 μl min-1 while...
The effect of droplet size, channel length and the amount of electromagnetic actuation force on reciprocating movement of mercury droplets in the magneto mercury reciprocating (MMR) micropumps
, Article Sensors and Actuators, A: Physical ; Volume 283 , 2018 , Pages 204-210 ; 09244247 (ISSN) ; Shafii, M. B ; Afshin, H ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Micropumps are regarded as one of the devices used in microsystems, which are responsible for pumping working fluid. The magnetic reciprocating micropump is an example of the existing micropumps in which the pumping agent includes three liquid metal droplets placed inside lateral channels and reciprocated by the electromagnetic force inside their channels. The working fluid located inside the main channel is pumped through due to the movement of these three droplets. The time duration in which the droplet traverses the sub-channel length is crucial in the operation of the suggested micropump. The present study aims to evaluate the effect of the length of sub-channels, moving droplet volume...
Electrical analogies applied on MMR micropump
, Article Sensors and Actuators, A: Physical ; Volume 301 , 2020 ; Afshin, H ; Shafii, M. B ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Micropumps are among useful equipment in microsystems. The magnetically actuated mercury micropump, which has been introduced for less than a decade, is an innovative kind of micropumps which uses mercury droplets motion as a pumping agent. The equations governing this micropump are complex and their numerical solution is a time-consuming process, due to electromagnetic, hydrodynamic, and unsteady effects. In the present study, for the first time, using simplifying assumptions, the performance of a Magneto Mercury Reciprocating (MMR) micropump with electromagnetic actuation is studied through electrical analogy and then, the components and operational stages of the micropump are simulated...
Design of the micropump and mass-transfer compartment of a microfluidic system for regular nonenzymatic glucose measurement
, Article Biotechnology Reports ; Volume 34 , 2022 ; 2215017X (ISSN) ; Saidi, M. S ; Kazemzadeh Hannani, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The aim of this paper is to design and numerically simulate the mass-transfer compartment and piezoelectric micropump of an implantable integrated microfluidic device for regular microdialysis-based nonenzymatic measurement of glucose level in diabetic patients. The device function is based on the process that the piezoelectric micropump pumps the dialysis fluid into the mass-transfer compartment microchannels, where the interstitial fluid (ISF) glucose diffusion into this dialysis fluid gives it a glucose content, then detected and measured in the sensor section. This diffusion takes place through the semipermeable membranes located in the microchannels at the base of the hollow...