Pump Height Research Articles

Efek tinggi hisap terhadap kapasistas pompa sentrifugal

Centrifugal pumps are one type of pump commonly used in the industry, particularly in the processing and distribution of clean water. The characteristics of these pumps can be determined by varying the flow rate at a certain height. A study was conducted to investigate the effects of three different pump heights (3.5 m, 4.5 m, and 5.5 m) on the efficiency of a centrifugal pump using water at a temperature of 31℃. The results showed that the maximum overall efficiency was obtained at a height of 4.5 m with a value of 33.22% and a total head of 23.39 m. The pump height was found to have an impact on the pump capacity, with higher pump positions resulting in an increased occurrence of cavitation bubbles in the suction pipe, leading to a decrease in pump performance. Therefore, the placement of centrifugal pumps should be carefully considered, taking into account factors such as height and distance of the suction pipe, to minimize cavitation and achieve optimal pump performance.

10 clinical tips for advancing patient safety when using syringe pump systems for microinfusion intravenous drug therapy.

10 clinical tips for advancing patient safety when using syringe pump systems for microinfusion intravenous drug therapy.

A magnetorheological flap valve micropump for drug delivery applications

In this paper, we propose a flap valve micro-fluidic pump that relies on an electromagnetic actuation mechanism. We employed a multiphysics-based simulation methodology to prove the proposed concept. More specifically, the complex and fully coupled magneto-solid-fluid interaction analyses were carried out via a two-dimensional, time-dependent computational model to determine the deformation of the upper wall of the pump chamber and the velocity field inside the pump channel. The simulations were performed in COMSOL Multiphysics software. The simulation approach was verified through a validity check study by replicating an existing study in the literature. Once verified, the full simulations were performed for the proposed concept. The performance characteristics of the pump were presented and discussed. In addition, a parametric study was conducted to see the effects of important design parameters on the net pumped volume, results of which were also presented and discussed. The proposed micropump can transfer 1.9 µL of fluid in one pumping cycle, which is almost two times the other micropump models. Also, the proposed flap valve can reduce the backflow up to 10 times during the expansion phase in comparison with the no valve model. The parametric studies demonstrated that the net pumped volume of the fluid is directly proportional to the channel height and valve spacing distance and is inversely proportional to the upper wall thickness, elastic modulus of the pump structure, width, height, and Poisson ratio of the valves. The proposed micropump could potentially be used in a broad range of applications, such as an insulin dosing system for Type 1 Diabetic patients, artificial organs to transport blood, organ-on-chip applications, and so on.

Flow rate accuracy of ambulatory elastomeric and electronic infusion pumps when exposed to height and back pressures experienced during home infusion therapy

ABSTRACTBackground: Elastomeric infusion pumps are widely used in the delivery of parenteral medications in the home, but real-life conditions may not match calibration or standardised testing conditions. This study investigated the impact of changes in infusion pump height and/or back pressure on infusion pump function.Methods: Volume delivered after one day, infusion duration, average and peak flow rates and time spent within stated accuracy were determined for four elastomeric and one electronic pump using gravimetric technique. Experiments were repeated after altering the height of the pump relative to the output (±40cm, ±20cm) and/or adding a back pressure (10-30mmHg) to the output of an attached catheter.Results: Under ideal operating conditions, the flow rate deviated from that specified by the manufacturer and between 88.5% and 99% of the total infusion volume was delivered. Varying the height or applying back pressure led to further changes in average flow rates and the volume of infusion solution delivered by the elastomeric pumps, but had little effect on the electronic pump.Conclusions: Clinicians should consider potential impact on drug delivery, safety and therapeutic effect for home infusion patients given variations in infusion pump performance observed in this study.

Herd factors influencing free fatty acid concentrations in bulk tank milk.

Free fatty acid (FFA) concentrations can be elevated in raw milk due to improper handling and management at the dairy farm, and high concentrations of FFA can lead to off flavors in milk. This study aimed to describe how the herd production system, milking system, feeding and technological factors impact on FFA concentrations in bulk tank milk. FFA concentrations in bulk milk samples from 259 organic and 3326 conventional herds were analyzed by FT-IR during one year. The FFA content was significantly lower in bulk milk from organic than conventional herds. This was most evident during the summer half-year when the organic cows graze pasture. Bulk milk from automatic milking systems (AMS) and tie-stalls contained greater concentrations of FFA than any other milking parlor systems. In AMS, high milking frequency was found to be the most significant contributor to elevated FFA content in milk. Moreover, a strong interaction was found between milking interval and production system (organic vs. conventional). The technical factors, pre-cooling, onset time for cooling after milk inlet, contact between milk and agitation also impacted on the FFA concentration, whereas other technical factors including centrifugal pump type, length and height of pumping line and type of AMS manufacturer were found to be without significant effect on FFA. Feeding variables, based on feeding plans and evaluation, only explained a small part of the variation in bulk milk FFA. Overall, this study demonstrated that AMS compared to other milking system contributes significantly to increased FFA concentration in bulk tank milk, and within AMS high milking frequency contributes to increased FFA concentration.

Aquaponic Growbed Water Level Control Using Fog Architecture

Integrated Multi-Trophic Aquaculture (IMTA) is an advance method of aquaculture which combines species with different nutritional needs to live together. The combination between aquatic live and crops is called aquaponics. Aquatic waste that normally removed by biofilters in normal aquaculture practice will be absorbed by crops in this practice. Aquaponics have few common components and growbed provide the best filtration function. In growbed a siphon act as mechanical structure to control water fill and flush process. Water to the growbed comes from fish tank with multiple flow speeds based on the pump specification and height. Too low speed and too fast flow rate can result in siphon malfunctionality. Pumps with variable speed do exist but it is costly. Majority of the aquaponic practitioner use single speed pump and try to match the pump speed with siphon operational requirement. In order to remove the matching requirement some control need to be introduced. Preliminarily this research will show the concept of fill-and-flush for multiple pumping speeds. The final aim of this paper is to show how water level management can be done to remove the speed dependency. The siphon tried to be controlled remotely since wireless data transmission quite practical in vast operational area. Fog architecture will be used in order to transmit sensor data and control command. This paper able to show the water able to be retented in the growbed within suggested duration by stopping the flow in once predefined level.

A liquid aluminum alloy electromagnetic transport process for high pressure die casting

For the electromagnetic transport (EMT) of liquid aluminum alloy during high pressure die casting (HPDC) by the plane induction electromagnetic pump (EMP), how to improve EMT efficiency and control EMT stationarity are key problems. Magnetic-flow coupling analysis was used to reveal effects of structural design and transport process parameters on EMT efficiency and stationarity. The output pump height of plane induction EMP was optimized by matching of iron core width W, coil width W′ and pump ditch width b, i.e., b values of bopt corresponding to 90% of the maximum output pump height, bopt/W=1.27 and bopt/W′=1. Both EMT efficiency and stationarity are achieved under the optimum transport current 32A. With the increase of the transport height from 350mm to 500mm, the EMT flow rate decreases from 4.28kg/s to 3.59kg/s, and the fillings of shot sleeve are always stationary. The transport tubes suffer a maximum positive pressure of 1.8×104Pa and a minimum negative pressure of −1.42×104Pa during EMT. For the liquid aluminum alloy soup occasions of 4.5kg, 6.5kg and 12.0kg, the transport time could be shortened significantly from manipulator’s 16s, 22s and 38s to EMT’s at most 2.195s, 2.75s and 4.28s, respectively. The developed EMT process with plane induction EMP for HPDC is a process with low cost, high transport efficiency and stationarity.

Simulative and Experimental Study on Electromagnetic Pump Supplying Liquid Alloys during Casting: Modeling and Effects of Design Parameters on Pump Height

The pump height (ΔH) of liquid A356 alloy by the plane induction electromagnetic pump supplying liquid aluminum alloys during casting was measured, and the experimental values agreed with 3D simulation results. It was found that the relationship between ΔH and frequency was relevant with structural design parameters, and the increase of ΔH versus frequency started to deviate from linearity when the width of the pump ditch (b) was higher than that of the iron core (W). ΔH was found to be always proportional to the square of the current and irrelevant with frequency and structural design parameters. It was also found that ΔH decreased significantly with the magnetic gap and increased with W and the thickness of the iron core, while ΔH was not affected by the polar distance. In addition, ΔH increased first rapidly and later slowly with b till the maximum was reached, after which ΔH started to decrease slowly with b.

Experimental Study of Airlift Pump Performance with S-Shaped Riser Tube Bend

Airlift pump is a type of deep well pu mps. Somet imes, it is used for removing water fro m mines or pumping slurry of sand and water or other solutions. The performance of airlift pu mp is affected by two sets of parameters; the geo metrical and operational parameters. The geo metrical parameters include p ipe diameter, pump height, design of air in jection system, and entrance geometry of the lift ing pipe; while the operational parameters involve submergence ratio, conditions of injected air, and nature of lifted phase. Conventionally, airlift pump with bent riser tube is less efficient than that with vertically straight riser tube. However, in real life situations, the use of local riser tube bend or flexib le riser tubes is considerably unavoidable. This work investigates experimentally the effects of local bends of the riser tube on the airlift pu mp performance. A series of experiments on a model airlift pu mp with three d ifferent riser tube configurations, based on the vertical position of local bends, were carried out. The local bends are in the form of an S-shaped like duct. The results showed that setting local bends of the riser tube near the air inject ion zone improves the airlift pump performance. However, imp rovement obtained in airlift pump performance is being negligible and, thus, the position of local bend of riser tube does not contribute to improvements in the perfo rmance of airlift pump.

3D simulation of plane induction electromagnetic pump for the supply of liquid Al–Si alloys during casting

The distribution and evolution of the magnetic flux, the induced current and the electromagnetic force in liquid A356 alloy in the pump ditch were revealed by the transient analysis. The magnetic flux was mainly along the height direction of the pump ditch and changed direction every interval of half cycle (T/2). The induced current formed two or three groups of swirl rings alternately along the length direction (X) of the pump ditch. The electromagnetic force contained the effective component (FMAGX) along +X direction and the invalid component that was centrosymmetric along the width direction of the pump ditch, and its change cycle was T/2. The magnetic flux, the induced current and the electromagnetic force all traveled along +X direction periodically. The effects of electromagnetic and structural design parameters on FMAGX and the pump height (ΔH) of the pump were obtained by the harmonic analysis. FMAGX and ΔH increased nearly linear with the frequency while decreased significantly with the magnetic gap, and they were proportional to the square of the current. FMAGX increased with the width (b) and the height (h) of the pump ditch, and ΔH first increased and later decreased with b while decreased monotonically with h.

A New Approach in the Design of High‐Risk Infusion Technology

The syringe infusion pump has been established as the instrument of choice for high‐risk infusions, where potent drugs are often delivered at low rates of flow. However, numerous instances of unexpected flow error with consequent patient physiological impact have been reported. These include unwanted bolus delivery on release of line occlusion, dosage fluctuation due to pump height change and fluid reflux within the multiple pump installations now common in the Intensive Care Unit (ICU). This article examines the performance of a typical ICU syringe infusion pump and identifies mechanical compliance, inherent in commercial designs, as a source of flow error that should not be ignored by equipment designers. A prototype low compliance system is described and tested with performance compared to the conventional design, demonstrating advantages in terms of lower flow error.

High risk infusions—accuracy compromised by changes in patient venous pressure

Intensive care often requires the simultaneous administration of high potency short half-life intravenous drugs. Numerous reported instances of unwanted transient flow characteristics such as bolus flow, slow start-up at set rate and fluid reflux—where fluid is found to flow away from the infusion site—have indicated a need for better understanding of the system dynamic. This article introduces a simple mathematical model of an infusion pump system, highlighting system mechanical compliance as a major contributory factor for flow error. The model is verified as correctly predicting flow variation caused by pump height change and is offered as an aid in the development of more accurate infusion devices. The accurate delivery of low flow rates requires small volume rigid components. This study also suggests that the current design of syringe infusion devices makes them susceptible to flow error caused by change in patient venous pressure.

Effect of changes in syringe driver height on flow: a small quantitative study

Objective: To quantify flow irregularities in drug delivery caused by vertical displacement of syringe pumps.Methods: A bench experiment was performed to quantify the effect of height on pumps used in our intensive care and theatre settings. A standard syringe pump and line set loaded with a dye solution was run through a graduated length of tubing, and the effect of changing pump height quantified by measuring progress down the tubing over time.Results: A 30 cm elevation produced significant drug delivery boluses — up to seven times the programmed rate at 2mL/h. Delivery rate increased in inverse proportion to the programmed rate, as did the time taken to return to the programmed rate. Lowering the pump 30 cm resulted in no-flow times of up to 180 seconds at a flow rate of 2mL/h — again inversely proportional to programmed rate.Conclusions: Vertical displacement of a common syringe pump by 30 cm produced significant bolus and cessation phenomena. These findings confirm the observations of previous authors and also demonstrate significant flow irregularities with smaller vertical displacements than previously tested. Further testing with other brands of pumps is required before a solution to this clinically important problem may be approached.

Focus on vacuum and cryogenics

Focus on vacuum and cryogenics

DEVELOPMENT OF ONE PIECE IMPLANTABLE BIVENTRICULAR ASSIST DEVICE BASED ON A MOVING ACTUATOR MECHANISM

An implantable left ventricular assist device (LVAD) is considered a useful therapeutic modality as a bridge-to-transplantation or bridge-to-recovery for patients with congestive heart failure. However, approximately 10% to 15% of all patients implanted with wearable LVADs have required right heart support with another device. However, unfortunately, there is no device that can be used as an implantable biventricular assist device (BVAD) so far. Our implantable BVAD is a volumetric coupled 1-piece unit including right and left blood sacs and an actuator assembly. The pump height is 67mm, width is 165mm and length is 162mm. The total weight is 780g. The moving-actuator, as an energy converter, utilizes a brushless DC motor generating a pendulous motion of itself by an epicyclic gear train. Both blood sacs are made of smooth, seam-free segmented polyurethane and manufactured to double layered structures, inner and outer blood sacs, which are contained within a rigid polyurethane chamber. The volumes of the left inner and outer blood sacs are 84 ml and 113 ml, and those of the right blood sacs are 71 ml and 95 ml, respectively. The compliance window made of polyurethane is a single layered structure with 600 μm thickness, and its area is 56 × 90 mm2. The interventricular space between the actuator and the sacs was filled with room air and silicon oil for the purpose of gear lubrication and heat dissipation. The compliance window together with the air within interventricular space plays a role of moderate passive filling and balancing output. A pressure sensor to measure the interventricular pressure (IVP) was attached, which informs the change of preload. An outflow cannula was made of Tygon tube (1/2 inch internal diameter) attached with ± 14 mm Dacron graft. The in vivo feasibility of the new device was evaluated with animal experiments. The ovine and bovine models were used as animal models. Among 17 cases, the best records were 28 days survival in ovine model and 23 days in bovine model. Now the BVAD is under development and design change is ongoing. Our one piece BVAD would be an alternative to heart transplantation especially in Korea or Japan where the cases of heart transplantation are fewer than 30 cases per one year. This work was supported by the Brain Korea 21 project.

Optimized performance of the Abiomed BVS 5000: adjustment of the pump height based on Doppler control of the flow pattern.

The Abiomed BVS 5000 is an automatic volume-driven paracorporeal pulsatile assist device providing left, right or biventricular support. The paracorporeal position allows optical adjustment of filling volumes of the device, which determines the output of the system. A procedure to adjust for maximal stable flow has not yet been established. In vitro measurements have been performed to assess the flow and pressure characteristics of the Abiomed BVS 5000 by raising the preload in 5 mmHg steps before running the system. Doppler probes were placed at the inflow and outflow lines of the pump. After setting the afterload at 80 mmHg the assist device was started. Two measurements were performed to find optimal flow (based on Doppler control and optical adjustment). (1) By Doppler control a stable flow pattern was found at a preload of 25 mmHg with a mean atrial pressure of 5 mmHg and a mean flow of 5.3 +/- 0.7 l/min (mean +/- standard deviation) at the inflow and outflow sites (the console flow was 4.8 +/- 0.4 l/min with a frequency of 61.8 +/- 2.0 l/min). (2) Optical adjustment of the pump height gave rise to a preload of 35 mmHg where we recorded a maximal atrial pressure of 107 +/- 5.8 mmHg, a maximal retrograde flow of -4.3 +/- 1.2 l/min at the inflow and -1.2 +/- 0.4 l/min at the outflow site. The mean flow at the inflow and outflow sites was 5.1 +/- 0.5 l/min (the console flow was 4.6 +/- 0.3 l/min with a frequency of 59.6 +/- 2.6 Hz). At an initial afterload of 60 and 40 mmHg the system showed the same qualitative behaviour, but the results were less accurate. Optical adjustment of the pump height may result in an atrioventricular valve insufficiency with undetected retrograde flow and high atrial pressures. We conclude that a Doppler flow probe must be placed at the inflow site to guarantee maximal stable flow.