Pump Device Research Articles

Analysis of flow characteristics and pressure pulsation in impeller region of shaft tubular pump device with different tip clearances

Analysis of flow characteristics and pressure pulsation in impeller region of shaft tubular pump device with different tip clearances

Evaluating Continuous Glucose Monitoring after Total Pancreatectomy with or without islet autotransplatation: A Scoping Systematic Review.

The review was conducted adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist. 15 studies including 147 patients (adult n = 71/paediatric n = 76) reported on CGM use post-TP (n = 42) and TPIAT (n = 105). 4 were randomized controlled trials and 10 observational studies. 6 studies evaluated CGM use in the peri-operative and 6 in the immediate post-operative period (n = 8) with variable follow-up (14 hours -20 months). CGM was used as a stand-alone device (8 studies) which allowed assessment of dynamic islet function and detection of hypoglycemia (n = 1) resulting in lower glucose levels (n = 1). 6 studies evaluated insulin pump with CGM with reduction in post-operative mean glucose (n = 4), and hypoglycaemic episodes (n = 2). There were no patient reported outcome measures (PROMs) or quality of life (QoL) measures reported. CGM can be used following TP for glucose monitoring and/or linked with insulin pump device in the peri-operative period with improved glycaemic control. However, the data are limited by short follow-up and lack of PROMs and QoL measures.

Evaluating the productivity of basement rock aquifers for sustainable groundwater development in sub-Sahara Africa using borehole pumping experiments and geophysical data

Ensuring all-year-round groundwater availability in the basement complex regions of sub-Sahara Africa requires careful combinations of strategies for exploration, development, and management of groundwater resources. The productivity of the basement aquifer of sub-Sahara Africa, SSA, was evaluated in terms of the volume of water produced per unit time, the aquifer transmissivity, hydraulic conductivity, specific capacity, and the thickness of the water-bearing zones using a suit of data from borehole pumping experiments, geophysical surveys, and lithologic logs from Opaque Field in sub-Sahara Africa. Findings from the study have been used to classify the basement complex aquifers of sub-Sahara Africa into three categories: marginally productive, low productive, and moderately productive. Weathered and fractured zones were found to be bright spots for groundwater storage, and aquifer productivity correlates with topography and the thickness of the weather zones. Most of the boreholes located on the low topographic heights were found to have the highest groundwater discharge, transmissivity, and hydraulic conductivity. Further, the study showed that the popular models used for estimating aquifer properties are unsuitable for basement complex aquifers. The results of the models are exaggerated when compared to the pumping test results. Cases of dry holes or poorly performing wells in the basement complex terrain may be attributed to the exaggeration. Consequently, two new and novel quantitative models were proposed and tested for evaluating the productivity parameters of basement aquifers of SSA for optimal selection of sites for groundwater development. The aquifer productivity maps computed with the new quantitative models show striking similarities to those computed from the pumping tests results and confirmed the appropriateness of the new quantitative models. The appropriate pumping device, pump operation time, and installation depth were recommended for the boreholes producing groundwater from the three categories of aquifers identified in this study.

Comparison of two pump-based systems for sampling small microplastics (>10 μM) in coastal waters

Microplastics (MPs) have emerged as an important research topic due to their ubiquity in the environment and their potentially harmful effects on aquatic biota. However, our knowledge of the abundance and characteristics of the smaller fraction of MPs (<300 μm) in marine waters remains limited. This study aims to compare two different filter pump devices: AAU-UFO (Universal Filtering Object) pump and KCD (KC Denmark's Micro Plastic Particle) pump for sampling small MPs (>10 μm). Coastal waters from six sites in the Gulf of Bothnia (Baltic Sea) were sampled with both devices. The concentration and composition of the collected MPs were analyzed by FPA-μFTIR imaging. The median concentrations were 117 MP/m3 with a median mass of 118 μg/m3 and 162 MP/m3 with a median mass of 117 μg/m3, for the UFO pump and KCD pump, respectively. The predominant MP shape was fragment, and the most abundant polymers were polyester, polyethylene, and polypropylene. MPs smaller than 300 μm represented more than 90% of the MPs in the samples. The recorded microplastic concentrations were several orders of magnitude higher than those previously reported using a Manta net in this area, highlighting the importance of analyzing MPs smaller than 300 μm. No significant differences in MP concentrations were found between samples from the two filter pumps, indicating that both devices are comparably effective systems for sampling MPs (>10 μm) in coastal waters. Overall, our findings contribute to harmonizing sampling methodologies for small MPs in aquatic systems, which is crucial for establishing effective monitoring programs and ensuring accurate risk assessments.

A Rootless Duckweed-Inspired Flexible Artificial Leaf from Plasmonic Photocatalysts.

The naturally existing leaves are ubiquitous two-dimensional flexible solar-to-chemical conversion systems that can run continuously in a sustainable manner. However, the current artificial photocatalytic systems are unable to achieve this due to the grand challenge in integrating existing photocatalysts in a flexible layout with high conversion efficiency and the ability to function independently. Here, we report on a rootless duckweed-inspired artificial leaf based on a lightweight, flexible, Janus plasmonic nanosheet-integrated sponge. The Janus plasmonic catalytically active nanosheet was made from self-assembled gold nanocube nanoassemblies grown on the porous sponges, which were further coated with an ultrathin palladium layer on one side via a ligand symmetry-breaking method. This sponge-based photocatalytic system is lightweight yet able to float on a water surface and conducts the gas-liquid reaction without auxiliary pumping and mixing devices. In a model reaction of 4-nitrophenol reduction, this floating leaf could achieve 2.5-fold and 65-fold higher efficiency than the corresponding dispersion and precipitation systems, respectively. The film theory is used to explain the sponge-based lightweight solar-to-chemical conversion system in a detailed kinetic and thermodynamic analysis, including the reaction rate constant, activation energy, enthalpy, entropy, Gibbs energy, and equilibrium constant.

A piezoelectric pump with composite vibrator for bubble resistance

Piezoelectric pumps, as microfluidic drive units, are widely used in microfluidic systems. Due to the fact that most piezoelectric pumps are driven by displacement, the introduction of air bubbles will produce a significant impact on their output performance. To minimize the adverse effect of air bubbles, a piezoelectric pump with composite vibrator (PPCV) is proposed. The composite vibrator consists of the active vibrator and the passive vibrator. By vibrating the passive vibrator in the pump chamber, it prevents bubbles retention. Multi-physics field simulation is established，which verifies the PPCV is feasible. Furthermore, a prototype is fabricated and experimentally investigated. At a voltage of 300 Vpp, the experimental results indicate a maximum output flow rate of 41.4 ml/min and a maximum output pressure of 18.7 kPa. After continuously entering 100 bubbles, the output performance of the PPCV decreases by less than 10 %, indicating that the PPCV owns excellent bubble resistance ability. The PPCV provides a new approach to microfluidic pumping devices.

Study on the impact of turbulent spatiotemporal propagation in the outlet passage on the performance of vertical axial flow pumps.

Abstract Pumping station engineering is crucial for our country’s national economy as a part of water conservancy infrastructure. The vertical axial flow pump commonly used in pumping station construction features a high flow rate and low discharge pressure. Understanding the impact of turbulence on the flow of water entering and leaving the pump unit is crucial for the efficient and reliable operation of a pumping station. This paper examines the internal flow and hydraulic characteristics of the device for vertical axial flow pump at a pumping station through numerical simulation technology and experimental validation. It is inferred that turbulent flow develops in the outlet flow passage while the pump device is currently functioning, impacting the impeller’s outlet bend and guide vane. This leads to the formation of vortices, backflow, and folding flow at the guide vane and outlet bend. As water flows out through the outlet passage, bias and backflow develop, causing erosion on both sides of the outlet pool and impacting the pump unit’s overall head and efficiency.

Numerical and experimental analysis of structural optimization and flow resistance effect of safety barrier based on a pump device

The safety barrier is often positioned at the entrance of the inlet passage in large and medium-sized low-lift pump stations, to ensure the safety of people and animals. To elucidate the blocking effect of the safety barrier and its influence mechanism on the internal flow of the inlet passage, numerical simulation combined with the physical model test were employed to investigate the impact of the cross-section and bar spacing of the safety barrier on the head loss, and the impact mechanism was clarified. The results showed that the optimal cross-section form of the safety barrier was found to be circular from the standpoint of head loss. When the blockage ratio of the safety barrier exceeds 0.3; prompt clearance of the blockage is recommended.

Numerical study on the optimization of the two-way passage division pier and the energy loss in the pumping device

Abstract The widespread utilization of the Two-way passage pumping device (TPPD) in riverside areas notwithstanding, there exists a notable inadequacy in quantitative research pertaining to its energy and hydraulic characteristics. On the basis of division pier optimization, the entropy production theory (EPT) with computational fluid dynamics is applied to analyse the energy loss characteristic of TPPD. The results show that after the optimization of the two-way passage division pier, the flow pattern in passages is improved, the vortex structure scale in passages is obviously reduced, and the hydraulic performance is improved. The predominant cause of energy loss within TPPD stems from turbulent dissipation due to fluctuations within the impeller, leading to the formation of irregular areas with heightened entropy production (EP) along the blade surface and within the impeller channel. Moreover, the energy loss within passages is predominantly localized near the centre of the pump unit.

Experimental study on energy and hydraulic performance of the axial flow pumping device with bell-shaped inlet channel

Abstract Due to the unique inlet design of the axial flow pump device with a bell shaped inlet channel, there is currently insufficient quantitative research on its hydraulic characteristics. This study investigates the hydraulic behavior of a vertical axial flow pumping device equipped with a bell-shaped inlet channel, analyzing various blade angles. Energy, cavitation, runaway, and pressure pulsation characteristics were assessed through meticulous testing on a high-precision test bench. Experimental findings indicate that altering the blade angle of the vertical axial flow pumping device with a bell-shaped inlet channel can influence its overall efficiency to some extent. Moreover, as the pump’s blade angle increases incrementally, the device’s cavitation performance gradually diminishes. Pressure pulsation tests reveal a relatively minor amplitude of pressure pulsation at the impeller outlet, contrasting with a more pronounced amplitude observed at the guide vane outlet compared to the pump outlet. These research results provide valuable insights for the design and optimization of actual pumping stations.

Study on flow characteristics and structural properties of vertical axial pump with low guide vane height

Abstract With the full construction of the South to North Water Diversion Project and the renovation of pumping stations, vertical axial flow pump devices have been widely used in various pumping station projects. This article uses the streamlined method to design the impeller and guide vanes of a vertical axial flow pump device. To analyze the hydraulic and structural characteristics, this paper uses CFD numerical simulation and fluid-structure interaction calculation methods. And the trend of output power change under different flow conditions was divided into three stages, elucidating the reasons for the sudden change in output power under flow conditions of 0.8Q-1.0Q. This article focuses on analyzing the internal flow state of the designed lower height guide vane segment to explore the problem of low guide vane height that is prone to occur during the design process. According to the research results, it is found that the lower height guide vane can also play a good role in stabilizing flow and recovering circulation under certain operating conditions. This article also studied the structural characteristics of the impeller and guide vanes, explaining the stress and strain distribution under design flow conditions.

Floating particles transport through the free surface vortex technique: A novel numerical study to assess the interaction among different scales of vortex structures

Fat, oil, and grease (FOG) floating particles in the sump of sewage pumping stations will accumulate together to form rigid layers, resulting in failure for pump device. To overcome this, the free surface vortex (FSV) technique has been considered and applied to transport floating particles toward the submerged suction pump inlet. This paper investigates the potential of vortices as a means of downward motion of FOG. The entrainment capacity of FSV is investigated by numerical simulations using a coupled level-set and volume-of-fluid method. Two coherent structures are decomposed by proper orthogonal decomposition: FSV represented by the first two orders with high energy content and spiral vortex bands represented by low energy and high order models. The extracted ridges of the finite-time Lyapunov exponent (FTLE) delineate different regions of the flow field and effectively capture the evolution of Lagrangian coherent structures. The floating particles in the sump are first caught by the dividing line formed by the FTLE ridges, mixed in the entrainment zone, and then merged into the vortex. The enstrophy production term dominates the development of vorticity. Subject to the influence of flow velocity gradients, both radial and tangential vortices undergo a transition into axial vortices. This transformation enhances the vortex's capacity to entrain particles within the vortex core area, leading to their rapid inward spiraling toward the vortex center and eventual expulsion due to the vortex's entrainment effect.

Encoding spatiotemporal asymmetry in artificial cilia with a ctenophore-inspired soft-robotic platform

A remarkable variety of organisms use metachronal coordination (i.e., numerous neighboring appendages beating sequentially with a fixed phase lag) to swim or pump fluid. This coordination strategy is used by microorganisms to break symmetry at small scales where viscous effects dominate and flow is time-reversible. Some larger organisms use this swimming strategy at intermediate scales, where viscosity and inertia both play important roles. However, the role of individual propulsor kinematics-especially across hydrodynamic scales-is not well-understood, though the details of propulsor motion can be crucial for the efficient generation of flow. To investigate this behavior, we developed a new soft robotic platform using magnetoactive silicone elastomers to mimic the metachronally coordinated propulsors found in swimming organisms. Furthermore, we present a method to passively encode spatially asymmetric beating patterns in our artificial propulsors. We investigated the kinematics and hydrodynamics of three propulsor types, with varying degrees of asymmetry, using Particle Image Velocimetry and high-speed videography. We find that asymmetric beating patterns can move considerably more fluid relative to symmetric beating at the same frequency and phase lag, and that asymmetry can be passively encoded into propulsors via the interplay between elastic and magnetic torques. Our results demonstrate that nuanced differences in propulsor kinematics can substantially impact fluid pumping performance. Our soft robotic platform also provides an avenue to explore metachronal coordination at the meso-scale, which in turn can inform the design of future bioinspired pumping devices and swimming robots.

Haemodynamic effects of intra-aortic balloon pumps stratified by baseline pulmonary artery pulsatility index.

Intra-aortic balloon pump (IABP) devices are commonly used in patients with heart failure related cardiogenic shock (HF-CS), including those with out-of-proportion right ventricular (RV) dysfunction. Pulmonary artery pulsatility index (PAPi) is a haemodynamic surrogate for RV performance. We aimed to assess short-term haemodynamic changes in patients with HF-CS following IABP support stratified by baseline PAPi. This is a single-centre study of 67 consecutive patients with HF-CS who underwent IABP placement between 2020 and 2022. The primary aim was haemodynamic changes of specific variables on pulmonary artery catheter monitoring over 72h following IABP placement. Secondary aims were clinically significant changes in diuretic regimens, changes in inotropes or vasopressors at 72h following IABP, along with clinical outcomes. Prior to IABP placement, 57% of the total cohort (median age 59years [48, 69], 31% female) had Society of Cardiovascular Angiography and Interventions Stage C HF-CS. Thirty-eight (56%) patients had a PAPi <2.0. Following 72h of IABP support, the PAPi <2.0 group had an observed significant decrease in central venous pressure (CVP; 20 to 12mmHg, P<0.001) and mean pulmonary artery pressure (mPAP; 37.5 to 28.5mmHg, P=0.001), and an increase in PAPi (1 to 1.6, P=0.001). No significant change in cardiac index (CI; 2 to 2.1L/min/m2, P=0.31) was observed. The PAPi ≥2.0 group (N=29) had no observed significant change in CVP (10 to 8mmHg, P=0.47), or PAPi (2.6 to 2.8, P=0.92), but there was a significant improvement in CI (1.9 to 2.5L/min/m2, P=0.004) along with reduction in mPA (37 to 29mmHg, P=0.03). The PAPi <2.0 group had a significant increase in diuretic requirement (52.6% vs. 20.7%, P=0.01) and numerically greater addition of inotropes/vasopressors (47.3% vs. 34.4%, P=0.07) compared with the PAPi ≥2.0 group at 72h following IABP placement. Significantly more patients in the PAPi ≥2.0 group underwent left ventricular assist device (55.2% vs. 26.3%, P=0.02), with no overall significant differences observed in escalation to veno-arterial extracorporeal membrane oxygenation, 30-day mortality, renal replacement therapy post-IABP, or rates of heart transplantation. IABP devices in those with HF-CS and low or abnormal PAPi may provide modest short-term haemodynamic benefits without significant improvement in CI, along with greater need for adjustment in medical therapeutics to achieve haemodynamic optimization.

SP2.10 - Early outcomes with the Insides Chyme Reinfusor (ICR) device in the management of parenteral nutrition dependent high output stomas (PN-HOS)

Abstract Aims PN-HOS represent a complex challenge, requiring input from surgical, gastroenterology and nutritional teams. Length of stay (LOS) is prolonged with difficulties in achieving output control and adequate nutrition with other associated risks. ICR is a modified stoma bag/mechanical pump and catheter device, reinfusing chyme into the distal limb, maintaining gut continuity, preserving enteral nutrient absorption and preventing distal limb atrophy. ICR may accelerate establishment of nutritional autonomy and reduce costs associated with PN/LOS. We report the largest study of ICR outcomes Methods Prospective study of ICR outcomes in patients with PN-HOS. Analysis included LOS, duration of PN, establishment of nutritional autonomy, nutritional markers, adverse ICR effects. Results Sixteen patients were trained to use the ICR (6M:10F). Median age 60yr. 75% achieved independent use (median 5.6 days). Overall usage was 395 days (median 32 days). Nutritional autonomy achieved in nine patients (pre-reversal). ICR increased median albumin 10.5 g/l. Adverse events included changing difficulties, spillage, noise, and discomfort. Two patients discontinued ICR because of pain/reflux. One patient died from unrelated post-operative complications. One patient with multiple loop stomas was successfully established on dual ICR. Nursing experience with ICR demonstrated ease of use and straightforward patient education. Cost analysis PN £5000/mth v ICR 1800/mth. Anecdotally at the time of reversal, surgical opinion was of much favourable bowel for anastomosis and return to function. Conclusions The ICR device is safe and contributes to restoration of nutritional autonomy. It reduces PN dependence with cost-benefits and acceptable adverse effects. At time of initial surgery distal limb should be fashioned to allow potential use of ICR.

On-Line Analysis of Cigarette Smoke Based on Microwave Plasma Torch Mass Spectrometry.

Cigarette smoke contains a large number of chemicals, including both flavor components and harmful substances. The mainstream smoke (MSS) generated by smoking is directly inhaled by individuals, making it crucial to establish an effective method for smoke detection and analysis. One promising technique for analyzing smoke is MPT-MS (Microwave plasma torch mass spectrometry). This approach offers several advantages in accurately detecting the composition of cigarette smoke. By combining MPT-MS with a smoke pumping device, we can achieve real-time online detection of smoke components. We successfully detected 22 flavor compounds present in the smoke. These compounds contribute to the distinct taste of cigarettes. Moreover, we identified 2 polycyclic aromatic hydrocarbons (PAHs) in the smoke. PAHs are known carcinogens and are of great concern in terms of their potential health risks. The successful detection and identification of flavor compounds and PAHs using our method confirm the online detection capability of MPT-MS. This approach provides an efficient and reliable means for analyzing the complex composition of cigarette smoke. By utilizing MPT-MS, we can gain valuable insights into the chemical composition of cigarette smoke and can inform the development of strategies and policies aimed at reducing the harmful effects of smoking and protecting public health.

Internal flow stability analysis of vertical mixed-flow pump device based on EGT and FFT

With the purpose of researching the internal flow stability of the vertical mixed-flow pump device (VMFPD), the entire flow field was solved through the very large-eddy simulation (VLES) k- ω model and the internal flow characteristics of the pump device were quantitatively analyzed with the use of the energy gradient theory (EGT) along with the physical parameters of the flow field. The research elucidates the variety rule of the pressure along the VMFPD and the energy gradient function K as well as the time-frequency features of the pressure pulsation (PP) in the impeller and guide vane. The results demonstrate that the solid wall restriction of the guide vane and the impeller rotation cause a significant shift in the velocity and direction of the water flow. This causes a significant pressure difference between the water bodies, which makes it easier to create an unstable flow. The suction surface of the impeller blade possesses the great concentration of the area with energy gradient function K &gt; 107, which is the critical area influencing the internal flow stability of the pump device.

Pressure Transient Solutions for Unbounded and Bounded Reservoirs Produced and/or Injected via Vertical Well Systems with Constant Bottomhole Pressure

Various analytical solutions for computing production and injection-induced pressure changes in aquifers and oil reservoirs have been derived over the past century. All prior solutions assumed a constant well rate as the boundary condition. However, in many practical situations, the fluid withdrawal from and/or injection into such subsurface reservoirs occurs with the aid of pump devices that maintain a constant bottomhole pressure in the well. Until now, how the well rate will decline over time, based on the pressure difference in the well relative to the initial reservoir pressure, could not be rapidly computed analytically (using the diffusivity as the key governing system parameter), because no concise expression had been derived with the boundary condition of a constant bottomhole pressure. The present study shows how the pressure diffusion equation can be readily solved for wells acting as sinks and sources with a constant bottomhole pressure condition. We consider both fractured and unfractured completions, as well as injection and production modes. The new solutions do not require an elaborate time-stepped pressure-matching procedure as in nodal analysis, the only other physics-based analytical method currently available to compute the well rate decline when a constant bottomhole pressure production system is used, which unlike our new method proposed here is limited to single well systems.

Descripting e + and Weyl fermion as beam/current for pump/injection semiconductor devices

Based on the demand for an improvement in various corpuscle types of current injection, the objective of this technique is to provide a new concept of carrier generators for optoelectronic pump and injection devices. This investigation is conducted to improve current injection by using a particle other than the electron. The idea was conceived from condensed matter physics for a technique to implement positron for carrier transport in semiconductors with the source based on localized emissions. A radioactive source such as 22Na is incident on a tungsten vane moderator, thus having positive electrons flowing and tunneling as well as a laser-driven high-quality positron into semiconductor-based devices. In addition, tantalum arsenide (TaAs) hosting Weyl particles has been discovered to hold significant potential for cutting-edge technological uses. Injection of different carriers and their behavior in semiconductors will lead to the emergence of solid state optoelectronics with different carrier injections that possesses a high energy (100–500 keV) and the possibility of maximum energy that is approximately several tens of megaelectron volts. Significantly, these various carrier sources have a larger range of operational settings and output characteristics due to their various underlying emission principles, thus obtaining a greater kinetic energy for a positron. The transformation to Weyl fermions carries electric charge via a device far more quickly than ordinary electrons, therefore unlocking the potential of new materials with unusual transport properties.

Microaxial flow pump (Impella CP®) in patients with ST-elevation myocardial infarction complicated by cardiogenic shock.

Cardiogenic shock due to ST-elevation myocardial infarction remains a critical condition with a high mortality rate, even with current revascularization techniques. The use of mechanical circulatory support, such as the microaxial flow pump device (Impella CP®), presents a promising approach to enhance cardiac output and systemic perfusion. The DanGer Shock trial explored the efficacy of Impella CP® in addition to standard care compared to standard care alone in improving survival outcomes for these patients. Despite the potential for increased adverse events, the Impella CP® device significantly reduces mortality in patients with ST-elevation myocardial infarction complicated by cardiogenic shock. Future research should focus on refining patient selection criteria and minimizing device-related complications to maximize the therapeutic benefits of mechanical circulatory support in this critical population.