Search Results (60)

Solar-driven irrigation, a promising clean technology for agricultural water conservation, is constrained by mismatched photovoltaic (PV) pump outflow and irrigation demand, alongside unstable PV output. While compressed-air energy storage (CAES) shows mitigation potential, existing studies lack systematic explorations of pump water-lifting characteristics and supply capacity under coupled meteorological and air pressure effects, limiting its practical promotion. This study focuses on a solar-coupled compressed-air energy storage regulated sprinkler irrigation system (CAES-SPSI). Integrating experimental and theoretical methods, it establishes dynamic flow models for three DC diaphragm pumps considering combined PV output and outlet back pressure, introduces pressure loss and drop coefficients to construct a nozzle pressure dynamic model via calibration and iteration, and conducts a 1-hectare corn field case study. The results indicate the following: pump flow increases with PV power and decreases with outlet pressure (model deviation < 9.24%); nozzle pressure in pulse spraying shows logarithmic decline; CAES-SPSI operates 10 h/d, with hourly water-lifting capacity of 0.317–1.01 m³/h and daily cumulation of 6.71 m³; and the low-intensity and long-duration mode extends irrigation time, maintaining total volume and optimal soil moisture. This study innovatively incorporates dynamic air pressure potential energy into meteorological-PV coupling analysis, providing a universal method for quantifying pump flow changes, clarifying CAES-SPSI’s water–energy coupling mechanism, and offering a design basis for its agricultural application feasibility. Full article

In view of the problems of high weed regeneration rate in traditional mechanical weeding and environmental risk in chemical weeding, a synergetic strategy of “mechanical damage + wound spraying mechanism” was proposed, and an intelligent weeding device combining synchronous cutting and spraying was designed to enhance the efficacy of herbicides and reduce their use. Focusing on the physical characteristics of weeds and the cutting mechanism, the analysis of the weed-cutting system and the force characteristics of the cutting tool were conducted. Key factors affecting cutting quality were identified, and their respective value ranges were determined. A targeted spraying system was developed, featuring a conical nozzle, DC diaphragm pump, and electromagnetic control valve. The Delta parallel manipulator, equipped with both the cutting tool and nozzle, was designed, and a kinematic model was established for both its forward and inverse movements. Genetic algorithms were applied to optimize structural parameters, aiming to ensure effective coverage of typical weed distribution areas within the working space. A simulated environment measurement was built to verify the motion accuracy of the manipulator. Field experiments demonstrated that the equipment achieved an 81.5% wound weeding rate on malignant weeds in the seedling stage at an operating speed of 0.6 m/s, with a seedling injury rate below 5%. These results validate the high efficiency of the integrated mechanical cutting and targeted spraying system, offering a reliable technical solution for green and intelligent weed control in agriculture. This study fills the blank of only focusing on recognition accuracy or weeding rate under a single weeding method, but lacks a cooperative weeding operation. Full article

Electromagnetic pumps are developed for industrial, medical and scientific applications, moving electrically conductive liquids and molten solder in electronics manufacturing using electromagnetism instead of mechanical parts. This study presents a comprehensive thermal analysis of an electromagnetic diaphragm pump, focusing on the influence of operating current, permanent magnet switching speed, and cooling conditions on pumping performance. The pump utilizes a flexible diaphragm embedded with a permanent neodymium magnet, which interacts with time-varying magnetic fields generated by electromagnets to drive fluid motion. Temperature monitoring is conducted using a waterproof DS18B20 sensor and an uncooled FLIR A325sc infrared camera, allowing accurate mapping of thermal distribution across the pump surface. Experimental results demonstrate that higher current and increased magnet switching speed lead to faster temperature rise, impacting the volume of fluid pumped. Incorporation of an automatic cooling fan effectively reduces coil temperature and stabilizes pump performance. Polynomial regression models describe the relationship between temperature, pumped liquid volume, and magnet switching speed, providing information to optimize pump operation and cooling strategies. The novel relationship between temperature and the volume of the pumped liquid is considered as a fourth-degree polynomial. In particular the model describes a quantitative evaluation of the effect of heating on pumping efficiency. An initial increase in temperature correlates with a higher pumped volume, but excessive heating leads to efficiency saturation or even decline. Indeed, mathematical dependencies are crucial in mechanical pump engineering for analyzing physical phenomena; this is achieved by using a mathematical equation to define how different physical variables are related to each other, enabling engineers to calculate performance and optimize the pump design. Full article

This study investigates the steady-state behavior of a four-way opposed diaphragm pump. Simulations and experimental results confirm that peak stress locations align with observed damage sites. During the return stroke, diaphragm flipping induces tension at the flow-fixed interface edges, creating stress concentrations that contribute to fatigue and failure. Particle image velocimetry (PIV) shows that, under constant flow, increased voltage enhances umbrella valve opening, accelerates movement, broadens flow distribution, and disrupts symmetry. At 90°, valve-edge velocity exhibits sharp, high-amplitude oscillations and a narrow, elongated return region. Vortices near the valve port interfere with fluid motion, causing pressure fluctuations and potential sealing issues or increased opening resistance. Higher flow rates intensify vortex strength and shift their position, generating diaphragm pressure differentials that alter flow direction and velocity, reducing stability and inducing secondary vortices. Compared to a modified diaphragm, the standard type shows more complex vortex structures, greater flow instability, and dynamic response degradation under identical pressure and varying flow. These fragmented vortices further disrupt flow, affecting pump performance. The findings provide design insights for diaphragm pump optimization. Full article

Prior research has proposed a basic configuration for a deep-sea mining system integrating slurry transport and wastewater discharge, and examined the operational characteristics of water-driven diaphragm pumps. Against the backdrop of commercial deep-sea polymetallic nodule exploitation, this study focuses on the technical design of seabed diaphragm pump groups and hydraulic parameter matching for a coupled slurry transport-wastewater discharge system. The solid–liquid two-phase output characteristics of the water-driven diaphragm pump were analyzed, leading to the proposal of a four-pump staggered configuration to ensure continuous particulate discharge throughout the full operating cycle. To meet commercial mining capacity requirements, the system consists of two sets (each with four pumps) operating with a phase offset to reduce fluctuations in slurry output concentration. A centralized output device was developed for the pump group, and a centralized mixing tank was designed based on analyses of outlet pipe length and positional effects. CFD-DEM simulations show that the combined effects of phased pump operation and centralized mixing tank mixing result in the slurry concentration delivered to the riser pipeline staying within ±1% of the mean for up to 57.8% of the system’s operational time. Considering the characteristics of both diaphragm and centrifugal pumps, the system is designed to output high-concentration slurry from the seabed diaphragm pumps, driven solely by wastewater, while centrifugal pumps provide lower-concentration transport by adding supplementary water from a buffer—thus reducing the risk of clogging. Under the constraints of centrifugal pump capacity, the system’s hydraulic parameters were optimized to maximize overall slurry transport efficiency while minimizing the energy consumption from wastewater discharge. The resulting configuration defines the flow rate and slurry concentration of the diaphragm pump group. Compared with conventional centrifugal pump-based transport schemes, the proposed system increases the slurry pipeline efficiency from 53.14% to 55.43% and reduces wastewater discharge-related pipeline resistance losses from 475.9 mH₂O to 361.7 mH₂O. Full article

Since the successful implementation of microfluidic technology in biomedical applications, research on micropumps—the central component of these systems—has gained significant momentum. Benefiting from advancements in pump materials and corresponding fabrication methods, micropumps have evolved from structurally complex mechanical designs to simpler non-mechanical configurations. This paper reviews well-developed mechanical micropumps, discussing their diaphragms, pump chambers, materials, and other aspects to outline their developmental trajectory and current applications, while also highlighting their limitations. After identifying the shortcomings of traditional micropumps, we introduce the concept of ferrofluid-based micropumps, emphasizing their structural simplicity, self-sealing capability, and recoverability. Previous research on ferrofluidic micropumps is summarized, demonstrating their superior performance in certain aspects. Finally, we provide an outlook on their potential applications in biomedicine and specialized fields. Full article

Background and Aims: Gastroesophageal reflux disease (GERD) is the most common esophageal disorder worldwide and a progressive condition leading to Barrett’s esophagus and adenocarcinoma. Continuous medical therapy with proton pump inhibitors fails to restore the antireflux barrier and is unable to relieve symptoms in up to 40% of patients. A tailored and standardized antireflux surgical procedure may increase cure rates and meet patient expectations. Methods and Results: Antireflux surgery aims to reestablish the natural antireflux barrier, which includes the diaphragmatic crura, the lower esophageal sphincter (LES), and the angle of His along with the gastroesophageal flap valve. For decades, the Nissen total fundoplication has been the primary procedure and remains the gold standard for surgical treatment. Alternatives such as Toupet partial fundoplication, Dor partial fundoplication, and the magnetic sphincter augmentation (LINX™) procedure have been developed to mitigate side effects like dysphagia, gas-bloat syndrome, and the inability to belch or vomit. Recent clinical findings regarding a novel procedure, RefluxStop™, indicate that restoring the gastroesophageal flap valve, in conjunction with anterior fundoplication and a silicone device for stabilizing the LES beneath the diaphragm, can achieve lasting reflux control and enhance patient-reported outcomes. Conclusions: The planning of healthcare services and actionable strategies to improve equity and quality of treatment is critical to address the global burden of GERD. Modern laparoscopic surgery for GERD is safe and effective and should be performed in centers offering a complete diagnostic pathway and specific surgical techniques tailored to the individual GERD phenotype. Shared decision-making between the surgeon and the patient is essential for the choice of operation. A personalized approach can offer clinical benefits over total fundoplication and improve patient-reported outcomes. Full article

Background: Even with advanced management involving pharmacologic and ventilatory strategies, respiratory dysfunction increases morbidity and reduces the quality of life. This narrative review examines how craniofacial and cervical manipulative interventions—including nasomaxillary skeletal expansion, breathing re-education, and structural techniques—may holistically optimize airway function by enhancing neurological and lymphatic dynamics, modulating vagal tone, reducing pharyngeal collapsibility, and supporting immune regulation across diverse clinical settings. Objectives: To explore manual techniques that influence respiratory and autonomic function and to evaluate their reported clinical efficacy and supporting evidence, particularly in the context of airway disorders such as asthma and pneumonia. Methods: A narrative review of the literature from PubMed and Google Scholar was conducted using search terms related to airway function and osteopathic manipulative techniques (OMTs). The inclusion criteria spanned 2010–2025 English-language peer-reviewed full-text articles on airway function, OMT, and emergency airway maneuvers. Clinical trials, observational studies, and reviews were included; non-peer-reviewed content and animal studies (unless mechanistically relevant) were excluded. Chapman’s reflexes related to respiratory function were incorporated to highlight somatic–visceral correlations. Key Findings: The techniques reviewed included frontal lift, vomer manipulation, maxillary and zygomatic balancing, and cervical adjustments. Thoracic OMT methods, such as diaphragm doming and lymphatic pump techniques, were also addressed. Emergency techniques, such as the BURP and Larson maneuvers, prone positioning, and high-frequency chest wall oscillation, were presented as comparative strategies to OMTs for acute airway management. Conclusions: Craniofacial and cervical manipulations can be a promising adjunct for enhancing airway function. However, the current literature displays heterogeneity and lack of large-scale randomized trials, which emphasize the necessity for standardized research and the establishment of clinical guidelines with the collected evidence. Full article

Gas bubbles are one of the main disturbances encountered when dispensing drugs of microliter volumes using portable miniaturized systems based on piezoelectric diaphragm micropumps. The presence of a gas bubble in the pump chamber leads to the inaccurate administration of the required dose due to its impact on the flowrate. This is particularly important for highly concentrated drugs such as insulin. Different types of sensors are used to detect gas bubbles: inline on the fluidic channels or inside the pump chamber itself. These solutions increase the complexity, size, and cost of the microdosing system. To address these problems, a radically new approach is taken by utilizing the sensing capability of the piezoelectric diaphragm during micropump actuation. This work demonstrates the workflow to build a self-sensing micropump based on artificial intelligence methods on an embedded system. This is completed by the implementation of an electronic circuit that amplifies and samples the loading current of the piezoelectric ceramic with a microcontroller STM32G491RE. Training datasets of 11 micropumps are generated at an automated testbench for gas bubble injections. The training and hyper-parameter optimization of artificial intelligence algorithms from the TensorFlow and scikit-learn libraries are conducted using a grid search approach. The classification accuracy is determined by a cross-training routine, and model deployment on STM32G491RE is conducted utilizing the STM32Cube.AI framework. The finally deployed model on the embedded system has a memory footprint of 15.23 kB, a runtime of 182 µs, and detects gas bubbles with an accuracy of 99.41%. Full article

Uniformity in material coating is not only essential for ensuring durability and long-term reliability but also for reducing costs, optimizing resources, and maintaining high-quality standards in industrial applications. Zinc phosphate is notable for coating steel surfaces due to its excellent corrosion resistance and adhesion properties in various industries. This study investigates the optimal flow rate of a diaphragm pump for achieving the effective and uniform coating of a steel cylinder. The coating uniformity was assessed using Scanning Electron Microscopy (SEM), focusing on layer thickness and elemental composition. A range of flow rates was analyzed to determine their influence on coating quality and regularity, with Energy-Dispersive Spectroscopy (EDS) revealing the distribution and homogeneity of the applied layer. The results identified a flow rate of 30 L/min as optimal with a thickness of 3.6 µm of coating on both sample sides, as it minimized surface defects and ensured consistent thickness across the cylinder. This study provides valuable insights for optimizing industrial coating processes, contributing to improved efficiency and reduced resource waste. Full article

Irrigation is crucial for agricultural production in dry regions. However, water salinity is a risk for the soil–plant combination and the longevity of the materials that make up the irrigation system. Drip irrigation using direct and intermittent photovoltaic pumping can be key for optimizing irrigation with saline water. This article compares two pump models to understand which has the greatest capacity to reduce the risks of salinity in irrigated agriculture, aiming to make the system more sustainable through more efficient irrigation, without the need for highly expensive corrective cleaning measures. The ideal pump was evaluated using the motor pump’s electrical and hydraulic parameters and the water’s quality parameters applied by irrigation. The results indicate that the diaphragm pump is more sensitive to disturbances in irrigation management when compared to the centrifugal pump; however, it stands out in the following areas: it is more efficient, that is, it operates for more hours of the day with a direct connection with the photovoltaic panels; delivers better distribution uniformity in both continuous and pulsed application; and it makes the drip irrigation system with saline water more resistant to clogging. Full article

In order to exploit the deep underground space, the construction of ultra-deep excavation in Shanghai is growing rapidly. In multi-aquifer strata, deep excavations typically require dewatering of confined aquifers to ensure engineering safety. However, existing studies have seldom conducted in-depth analysis on the influence of the soil parameters and construction measures on the deformation of retaining structures. In this study, a three-dimensional hydro-mechanical numerical model was developed to evaluate the performances of excavation and dewatering of the foundation pit. The model was validated by comparing the calculated and measured wall deflections and groundwater drawdowns of a 45 m ultra-deep double-wall excavation in Shanghai. According to the characteristics of soil stratification and construction activities, three parameters were selected for subsequent analysis, including the hydraulic conductivity of aquitard below the bottom of the pit, the pumping rate in the second confined aquifer and the construction of TRD wall. The stress distributions on both sides of the diaphragm wall were examined to elucidate the deformation mechanism. The results indicate that the aquitard hydraulic conductivity directly affects the effective stress of the overlying aquifer, which plays a crucial role in resisting wall deflection. An increase in the hydraulic conductivity leads to smaller effective stress, greater wall deflection and larger ground settlement. While an appropriately increased pumping rate enhances effective stress, over-pumping may induce excessive wall deflection at depth and disproportionate ground settlement. The TRD wall is quite useful in terms of waterproofing but the effect on deformation control is limited. The findings of this study provide valuable insights for engineering practices and the optimization of deep excavation construction measures in multi-aquifer strata. Full article

This work involves the development of a hydrodynamic fertilizer injector (HFI), which uses an integrated axial-flow turbine (AFT) and a diaphragm pump to absorb liquid fertilizer. Three structural parameters—the number of impellers (M₁), average number of blades per impeller (M₂), and arrangement pattern (M₃)—are considered, and 12 AFT designs are developed. Using a combination of CFD numerical simulations and hydraulic performance testing, the response of the AFT output power (P), blade negative pressure (NP), and fertilizer injection flow rate (Q_inj) to structural parameters and inlet pressure (H) is investigated. The results show that the normalized root mean square error between the simulated outlet flow rate (Q_s) and the measured flow rate (Q_m) is 5.1%, indicating high accuracy in the grid motion simulation method. P increases first and then decreases with the increase in impeller speed (n). The maximum P (P_max) ranges from 150.1 to 201.4 W. P_max increases with H, decreases with increasing M₁ and M₂, and shows little change with M₃. At H = 0.14 MPa, M₁ and M₂ have a significant influence, and at H ≥ 0.14 MPa, M₁ becomes the most significant factor (p < 0.05). Low-speed flow and negative pressure cavitation zones at the leading edge of the blade suction surface cause flow blockage and affect the lifespan of the AFT. These regions decrease in size as H increases but increase with M₁. The negative pressure (NP) decreases as M₂ increases. When M₁, M₂, and M₃ are 2, 3, and identical (D33), the P_max of the AFT is maximized, increasing by 6.7% to 33.5% compared with those of the other combinations. The Q_inj of D33, D34, D43, and D44 at H = 0.12~0.18 MPa range from 288.6 to 847.3 L/h, which is 38.7% to 461.0% higher than that of domestic and international venturi injectors. When considering cavitation issues and the manufacturing cost of the AFT mold, D44 may be chosen. Although its Q_inj is 7.0% lower than that of D33, NP is reduced by 37.9%. These findings provide a basis for the development of the HFI with AFT as the driving unit. Full article

The diaphragm is the primary muscle involved in the ventilatory pump, making it a vital component in mechanical ventilation. Various factors in patients who require mechanical ventilation can lead to the deterioration of the diaphragm, which is associated with increased mortality. This deterioration can arise from either excessive or insufficient support due to improper adjustment of ventilation programming variables. It is essential for healthcare professionals to make appropriate adjustments to these variables to prevent myotrauma, which negatively impacts muscle structure and function. One recognized cause of muscle injury is eccentric work of the diaphragm, which occurs when muscle contractions continue after the expiratory valve has opened. Current evidence suggests that these eccentric contractions during mechanical ventilation can be harmful. This brief review highlights and analyzes the existing evidence and offers our clinical perspective on the importance of properly adjusting ventilation programming variables, as well as the potential negative effects of eccentric diaphragm contractions in routine clinical practice. Full article

Current trends in the development of technology are linked inextricably to the increasing level of automation in technological processes and production systems. In this regard, the development of systems for supplying working fluids with adjustable pumps that have high performance characteristics, an increased service life and low operating costs is an important scientific and technical task. A primary challenge in the development of such systems lies in achieving low fluid flow rates while maintaining stable operating characteristics. This challenge stems from the fact that currently available controlled hydraulic pumps exhibit either a high cost or suboptimal life and efficiency parameters. This work focuses on the development of a plunger hydraulic pump with a small working volume. A mathematical model has been developed to investigate the characteristics, optimize the design of this pump and further expand the size range of such pumps. The solution was implemented on a computer using the dynamic modelling environment MATLAB/Simulink. In order to verify the mathematical model’s adequacy, a plunger pump prototype was built and integrated with a test bench featuring a measurement system. The test results showed higher pump efficiency and a significant reduction in hydraulic losses. An analysis of the obtained data shows that the pump is characterized by increased efficiency due to optimal flow distribution and reduced internal leakage, which makes it promising for use in hydraulic systems requiring improved operating characteristics. The developed pump has more rational characteristics compared to existing alternatives for use in water supply systems for induction superheaters. The experimental external characteristics of the developed pump are 10% higher than the external characteristics of the ULKA EX5 pump selected as an analogue, and the pressure characteristics are 65% higher. It offers production costs that are several times lower compared to existing cam-type plunger or diaphragm pumps with oil sumps and precision valve mechanisms. Additionally, it has significantly better operating characteristics and a longer service life compared to vibrating plunger pumps. Full article