Impedance Induce Valve Pump in Closed Loop System

2013 ◽  
Vol 393 ◽  
pp. 747-752 ◽  
Author(s):  
M. Mazwan Mahat ◽  
M. Arif Sulaiman ◽  
Chee Sheng Ow ◽  
Rosnadiah Bahsan ◽  
N. Merlisa Ali ◽  
...  
Keyword(s):  
Flow Rate ◽  
Liquid Velocity ◽  
Supply Voltage ◽  
Volume Flow Rate ◽  
Elastic Tube ◽  
Closed Loop System ◽  
Flexible Tube ◽  
Impedance Pump ◽  
Pump Mechanism ◽  
Set Up

This paper summarises a study which aims to develop and analyze the performance of the valveless impedance pump. Mechanism of valveless impedance pump is to apply acoustic impedance mismatch in order to drive the flow and also consists of a flexible connection at the ends to the more rigid sections. Characteristics of liquid velocity and pressure at the pump base valveless impedance at various supply voltage and different frequencies have been discovered through experimentation. Secondly, this research also aims to discuss the effect volume flow rate (millitres / min) in the elastic tube impedance based on different parameters of the pump pinch. The variation of pinch location and pinch width are also available through the results of this study. This study begins with the design set up to use the software and followed by installing all equipment used for the experiments. Then, this study continues to get results and make an analysis of the impedance pump by experimentation. Results found that all the parameters used in this experiment affect the flow rate in the impedance pump. Additional experiments on the effect of the thickness of the flexible tube on the flow rate gave lower values when the flexible tube is relatively thicker.

Valveless Pump in Closed Loop Tube System

2014 ◽  
Vol 607 ◽  
pp. 561-564
Author(s):  
M. Mazwan Mahat ◽  
Izdihar Tharazi ◽  
Liyana Roslan ◽  
Mohd Fakrul Jasni
Keyword(s):  
Flow Rate ◽  
Supply Voltage ◽  
Volume Flow Rate ◽  
Research Work ◽  
Maximum Flow ◽  
Elastic Tube ◽  
Working Fluid ◽  
Future Design ◽  
Valveless Pump ◽  
Impedance Pump

This research work aims to identify the characteristic of flow in valveless impedance pump which uses acoustic impedance mismatch to drive flow. The experimental setup mainly focuses on the elastic section connected between two ends of rigid tube. Fluid flow rate resulting from the pumping mechanism were measured at different supply voltage. Meanwhile, the volume flow rate (ml / min) in the elastic tube section were also determined based upon different pinch location and width using water as a working fluid. In order to achieve these parameters quantification, the experimental test rig was designed and the set of equipments were successfully assembled. Then, the measured parameters resulting from the experiment of the impedance pump are presented in significant findings of four curves plots. It is found that the maximum flow rate occurred at voltage setting equal to 4 V. Significantly, results obtained could beneficial future design as a mimics model for novel Ventricular Assist Device use in cardiac patient as well as further explanation about the factor that influence the characteristic of valveless impedance pump.

Experimental Study on the Effect of Pinch Parameters and Fluid Viscosity to Flow in Closed Loop Impedance Pump

2014 ◽  
Vol 660 ◽  
pp. 932-936
Author(s):  
M. Mazwan Mahat ◽  
R.N. Izzati ◽  
Ilya Izyan Shahrul Azhar ◽  
Izdihar Tharazi
Keyword(s):  
Fluid Flow ◽  
Flow Rate ◽  
Supply Voltage ◽  
Maximum Flow ◽  
Elastic Tube ◽  
Fluid Viscosity ◽  
Ventricular Assist ◽  
Tube Section ◽  
Impedance Pump ◽  
Device Use

This paper aims to analyse the performance of impedance pump that uses energy mismatch to drive fluid flow. The experimental setup mainly focus to establish the relationship between the fluids flow rates in elastic tube section connected between two ends of solid tube and pinch mechanism location as well as fluid viscosity. Measurement of fluid flow rate or representation of its velocities resulting from the pumping mechanism is measured using two different supply voltage and constant pincher width. These measured parameters resulting from the pinch mechanism of the elastic tube section were varied at different pinch location along itsx-axis direction; divided into two main cases namely (1) 2 V and (2) 3 V at 40 mm to 140 mm pinch location. From the voltage variation, it is found that the maximum flow rate given by voltage 3.0 V at pinch location 40 mm while for the effect of viscosity, the highest flow rate is 93 ml/min. The profiles obtained revealed the characteristic of valve less pump to be the new model of new Ventricular Assist Device use in cardiac patient as well as further explanation about the factor that influence the characteristic of elastic tube.

MEASUREMENT OF FLOW IN CIRCULAR ELASTIC TUBE

2015 ◽  
Vol 76 (10) ◽  
Author(s):  
Muhamad Mazwan Mahat ◽  
Salmiah Kasolang ◽  
Izdihar Tharazi ◽  
R. Nazirul Izzati
Keyword(s):  
Structural Parameters ◽  
Circulatory System ◽  
Elastic Tube ◽  
Tube Length ◽  
Working Fluid ◽  
Circulatory Support ◽  
Pump System ◽  
Initial Work ◽  
Impedance Pump ◽  
Set Up

 Impedance pump is a simple valveless pumping mechanism which typically used in viscosity measurement device to assist pumping of fluid. It is typically connected to an elastic tube in a circulatory system of a more rigid tube. In conventional mechanical circulatory support systems using rotary pump, the pumping mechanism was exposed to turbulent stresses. Hence,  this may cause damage to blood cells flowing through the impeller. There has been initial work on finding alternative solution using the impedance pump system. However,  substantial findings are not yet sufficient to fully understand the mechanism. The purpose of this research is to extend the investigation on impedance pump by specifically looking at the effect of structural parameters on the elastic tube and the flow behaviour. In this study, a closed loop impedance pump system was set up to demonstrate blood flow circulatory system where the mixture of glycerine and water was used as the working fluid. Three variables were regulated namely voltage, tube thickness, and tube length was used in order to get the flowrate of the working fluid. Based on the results, it was found that  tube thickness of 1 mm and a length of 200 mm had produced the highest flowrate in the region 75 ml/min.

Net flow generation in closed-loop valveless pumping

2020 ◽  
Vol 234 (11) ◽  
pp. 2126-2142 ◽  
Author(s):  
Christos Manopoulos ◽  
Sokrates Tsangaris ◽  
Dimitrios Mathioulakis
Keyword(s):  
Flow Rate ◽  
Closed Loop ◽  
Simultaneous Recording ◽  
Elastic Tube ◽  
Fluid Medium ◽  
Flexible Tube ◽  
Flow Generation ◽  
Valveless Pumping ◽  
Valveless Pump ◽  
Flexible Walls

Net flow generation in valveless pumping, met in many physiological applications and recently in micropumping devices, constitutes an open fluid dynamics issue due to the complex interaction between the fluid medium and the flexible walls of the pump. In the context of the present experimental work, the conditions of the net flow generation are examined in a closed-loop horizontal valveless pump, which consists of a rigid and an elastic tube of equal diameters and lengths, and a pincher that forces the liquid within the tube to oscillate at Reynolds and Womersley numbers up to 7800 and 48, respectively. Pinching off as well as at the mid-length of the pump flexible tube, net flow is generated at certain pinching frequencies for which details are presented based on simultaneous recording of the pressure at the two tube junctions, the flow rate and the displacement of the pincher. Pinching off the mid-length of the pump at low pinching frequencies, net flow rate is practically null due to the almost identical pressure waveforms at the tube junctions, which vary in phase with the pincher motion. However, close to the first natural frequency of the hydraulic loop, the reflection of the pressure waves at the tube junctions combined with their increased phase difference cause high axial pressure gradients, which when they increase simultaneously with the squeezing of the tube, net flow rate maximization occurs. Pinching at the flexible tube mid-length area, nonzero net flow rates can also be generated, the sign of which changes when the pincher mid-point crosses the tube mid-length without being nullified.

Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

1989 ◽  
Vol 47 ◽  
pp. 1000-1001
Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby
Keyword(s):  
Electron Microscopy ◽  
Flow Rate ◽  
Succinic Anhydride ◽  
Volume Flow Rate ◽  
Mass Density ◽  
Uranyl Acetate ◽  
Volume Flow ◽  
Base Resin ◽  
And Performance ◽  
Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

On the Influence of the Slot Orifice in Diesel Common Rail Nozzle

2018 ◽  
Vol 11 (1) ◽  
pp. 55-69 ◽  
Author(s):  
Giancarlo Chiatti ◽  
Ornella Chiavola ◽  
Fulvio Palmieri ◽  
Roberto Pompei
Keyword(s):  
Cross Section ◽  
Flow Rate ◽  
Experimental Analysis ◽  
Common Rail ◽  
Spray Angle ◽  
The Novel ◽  
Hydraulic Behavior ◽  
Reference Information ◽  
Light Duty ◽  
Set Up

Background:The paper deals with a diesel common rail nozzle in which a novel orifice layout is implemented.Objective:Its influence on the nozzle mechanical-hydraulic behavior and on the spray shape transient development is experimentally investigated.Methods:In the research, a solenoid injector for light duty diesel engines is equipped with the novel nozzle prototype and tested. The prototype layout is described, pointing out the features of the nozzle orifices, in which a Slot cross-section is adopted; the investigation is accomplished extending the hydraulic tests and the spray visualizations to a reference nozzle with standard holes. The influence of the hole layout on the mechanical-hydraulic behavior of the nozzle is assessed by experimental analysis based on the rate of injection measurement, in comparison with the reference nozzle. Once the hydraulic behavior of the novel nozzle has been characterized in terms of mass flow rate, the slot influence on the spray shape is assessed analyzing the macroscopic features such as the penetration distance and the spray angle, in non evaporative conditions. The study is carried out under transient injection conditions, for different injection pressures, up to 1400 bar.Results:The results on spray characteristics also provide reference information to set up spray models suited to take the Slot orifice into account.

scholarly journals Angiotensin II stimulates trafficking of NHE3, NaPi2, and associated proteins into the proximal tubule microvilli

2010 ◽  
Vol 298 (1) ◽  
pp. F177-F186 ◽  
Author(s):  
Anne D. M. Riquier-Brison ◽  
Patrick K. K. Leong ◽  
Kaarina Pihakaski-Maunsbach ◽  
Alicia A. McDonough
Keyword(s):  
Angiotensin Ii ◽  
Proximal Tubule ◽  
Flow Rate ◽  
Enzyme Inhibitor ◽  
Volume Flow Rate ◽  
Ang Ii ◽  
Sprague Dawley ◽  
Water Reabsorption ◽  
Associated Proteins ◽  
Gradient Fractionation

Angiotensin II (ANG II) stimulates proximal tubule (PT) sodium and water reabsorption. We showed that treating rats acutely with the angiotensin-converting enzyme inhibitor captopril decreases PT salt and water reabsorption and provokes rapid redistribution of the Na+/H+ exchanger isoform 3 (NHE3), Na+/Pi cotransporter 2 (NaPi2), and associated proteins out of the microvilli. The aim of the present study was to determine whether acute ANG II infusion increases the abundance of PT NHE3, NaPi2, and associated proteins in the microvilli available for reabsorbing NaCl. Male Sprague-Dawley rats were infused with a dose of captopril (12 μg/min for 20 min) that increased PT flow rate ∼20% with no change in blood pressure (BP) or glomerular filtration rate (GFR). When ANG II (20 ng·kg−1·min−1 for 20 min) was added to the captopril infusate, PT volume flow rate returned to baseline without changing BP or GFR. After captopril, NHE3 was localized to the base of the microvilli and NaPi2 to subapical cytoplasmic vesicles; after 20 min ANG II, both NHE3 and NaPi2 redistributed into the microvilli, assayed by confocal microscopy and density gradient fractionation. Additional PT proteins that redistributed into low-density microvilli-enriched membranes in response to ANG II included myosin VI, DPPIV, NHERF-1, ezrin, megalin, vacuolar H+-ATPase, aminopeptidase N, and clathrin. In summary, in response to 20 min ANG II in the absence of a change in BP or GFR, multiple proteins traffic into the PT brush-border microvilli where they likely contribute to the rapid increase in PT salt and water reabsorption.

Multi-objective optimization of squirrel cage fan for range hood based on Kriging model

2021 ◽  
pp. 095440622199586
Author(s):  
Qianhao Xiao ◽  
Jun Wang ◽  
Boyan Jiang ◽  
Weigang Yang ◽  
Xiaopei Yang
Keyword(s):  
Flow Rate ◽  
Optimization Design ◽  
Volume Flow Rate ◽  
Kriging Model ◽  
Volume Flow ◽  
Design Parameters ◽  
Multi Objective Optimization ◽  
Nsga Ii ◽  
Multi Objective ◽  
Squirrel Cage

In view of the multi-objective optimization design of the squirrel cage fan for the range hood, a blade parameterization method based on the quadratic non-uniform B-spline (NUBS) determined by four control points was proposed to control the outlet angle, chord length and maximum camber of the blade. Morris-Mitchell criteria were used to obtain the optimal Latin hypercube sample based on the evolutionary operation, and different subsets of sample numbers were created to study the influence of sample numbers on the multi-objective optimization results. The Kriging model, which can accurately reflect the response relationship between design variables and optimization objectives, was established. The second-generation Non-dominated Sorting Genetic algorithm (NSGA-II) was used to optimize the volume flow rate at the best efficiency point (BEP) and the maximum volume flow rate point (MVP). The results show that the design parameters corresponding to the optimization results under different sample numbers are not the same, and the fluctuation range of the optimal design parameters is related to the influence of the design parameters on the optimization objectives. Compared with the prototype, the optimized impeller increases the radial velocity of the impeller outlet, reduces the flow loss in the volute, and increases the diffusion capacity, which improves the volume flow rate, and efficiency of the range hood system under multiple working conditions.

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