Suction Capacity Research Articles

Determining the Suction Capacity of Compacted Clays with Fuzzy-Set Theory

Water suction capacity is an important parameter affecting the swelling properties and volumetric change of soil. Determination of the water suction capacity is made by the experiments which are needed long time in laboratory. However, this has random errors due to the heterogeneous and anisotropic structure of soil sample together with the error caused by the operator made the experiment. Such an estimation problem, included the errors, may be easily solved with the fuzzy-set theory. In this study, the suction capacity of compacted clayey soils is predicted with the fuzzy-set theory. For this reason, the engineering properties of clayey soil (plasticity index, dry density, initial water content and suction capacity) are partitioned into fuzzy subsets, and fuzzy rules are formed. Later, a computer program in the Fortran language is written to estimate the suction capacity of compacted clayey soil from these properties. It is shown that there is a good similarity between the results of the tests and proposed fuzzy logic model.

Limitation on the Number of Groundwater Well Pumps in the Coastal Area of Ternate Island

The hydrogeological characteristics of small volcanic islands possess unique attributes. Groundwater flow patterns descend radially and converge in coastal aquifers. The uneven distribution of coastal aquifers sometimes leads communities to extract groundwater from specific points. A notable phenomenon observed in the study area is the presence of dug wells with multiple water pumps. If the combined suction capacity of these pumps exceeds the allowed limit, it has the potential to cause the mixing of saltwater with freshwater. This study utilizes geoelectric methods to delineate the groundwater-saltwater interface beneath the surface. The groundwater-saltwater interface can also be calculated using equations. By knowing the well positions with multiple pumps, it is possible to calculate the allowable number of pumps. The calculations yield a limit of up to 31 pumps per dug well, thereby mitigating the risk of saltwater intrusion. Furthermore, data on the dug well positions within the study area are used to create groundwater table contours and flow models, aiding in the analysis of saltwater pollutant dispersion in the event of intrusion.

Experimental and numerical research on the coupled mechanisms of cavitation effect in a Venturi-type bubble generator

Venturi type bubble generator has a broad application in various fields and its bubble performance is closely related to the strong turbulent flow field. The interaction between bubble breakup and cavitation flow is not fully explained. In present work, the influence of cavitation on the suction performance and gas-phase transport pattern of a Venturi-type bubble generator is investigated by experiments and numerical simulations. The results show that the pressure ratio of 0.58 is the critical cavitation condition and the suction of the Venturi type bubble generator reaches the limiting value. The Venturi type bubble generator almost lost its suction capacity at the pressure ratio decreased to 0.27. However, the cavitation effect has a suppressive effect on the suction volume. The quasi-periodicity of the air inlet velocity pulsation and cavity development is highly consistent. Further research found that the blocking effect formed by return jets and pressure waves from cavity collapse is the main factor in reduced suction volume. The mechanisms of cavity shedding and collapse have a similar evolutionary model to the bubble breakup mechanisms in the Venturi-type generator.

Percutaneous dilatational tracheostomy guided by rigid bronchoscopy in patients with cervical mass

Herein, we proposed the PDT guided by rigid bronchoscope in intubated patients with airway obstruction. The presence of cervical mass discouraged us to perform an open tracheostomy as it could result in more blood loss than PDT, while the use of rigid bronchoscopy rather flexible bronchoscopy could facilitate the execution of PDT due to better visibility and suction capacity. This strategy was successfully applied in three consecutive intubated patients with airway obstruction due to cervical mass.

Experimental and simulation investigation of the impact of rotational speed on the performance of radial-flow gas wave ejector

The gas wave ejector (GWE) is a device that enables energy transfer between gases at different pressures through pressure waves. We conduct an experimental and simulation study on a novel radial-flow GWE, named DUT-R1, designed to harness centrifugal force to enhance mass and energy transfer efficiencies. Considering the significant influence of rotational speed (n) on the pressure waves and flow losses, we examine the relationship between the n of the DUT-R1 and both its ejection rate (ξ) and total efficiency (ηT).Experimental data demonstrate that the GWE can attain the highest ξ and ηT at an optimal designed rotational velocity (nd) when the pressure ports remain fixed. Simulations suggest that the primary cause can be attributed to the disruption of the ideal wave system. And when the equipment is equipped with ports matched to the nd, a consistent increase ξ is observed as the nd increases from 2000 r/min to 4000 r/min, resulting in a maximum improvement of 13.25 %. The simulation results demonstrate that increasing n enhances the suction capacity of the equipment through the inputting of shaft power (P). However, ηT initially increases and then decreases as the nd increases, with a maximum improvement of 11.86 %. The simulation provides an explanation for the observed variations in ηT during the experimental investigation by illustrating that flow losses initially decrease and then subsequently increase with an increasing value of n.

The technology of using a jet pump to increase the efficiency of vertical drainage

Vertical drainage systems, which rely on pumps and tube wells, are widely recognized for their effectiveness despite drawbacks such as high costs and significant energy consumption. In a recent study, the integration of a jet pump into vertical drainage systems was explored to enhance their efficiency. A specialized laboratory setup was developed to examine the use of a jet pump within these systems. The research focused on understanding how the diameter of the pressure pipe affects the jet pump’s suction capabilities. It was found that the jet pump operated at its highest efficiency, 50%, with a pressure pipe diameter of 40 mm. Statistical analysis of the laboratory data led to the formulation of a relationship for estimating both the suction capacity and suction height of the jet pump in the enhanced vertical drainage system.

Dysfunctional suction dynamics in newborns with ankyloglossia.

Compare infant suction in babies with and without ankyloglossia using a microprocessor-controlled pressure sensor coupled to a pacifier. Fifty-five infants from 0 to 2 months of age underwent clinical examination for ankyloglossia, after which they were offered a silicone pacifier connected to the pressure acquisitiondevice and suction activity was recorded. Thus, we extracted the frequency of sucks within a burst, the average suck duration, the burst duration, the number of sucks per burst, the maximum amplitude of sucks per burst and the inter-burst interval. The key difference in newborns with ankyloglossia in relation to control was that they perform longer bursts of suction activity. The longer burst durations are likely a compensatory strategy and may underlie the pain reported by mothers during breastfeeding. We therefore propose a method for objectively quantifying some parameters of infant suction capacity and demonstrate its use in assisting the evaluation of ankyloglossia.

Protocolo diagnóstico y terapéutico de la hemoptisis

The medical record allows us to make a precise diagnosis and evaluate the severity of an episode of hemoptysis. A simultaneous evaluation and approach are essential for treatment success. The main objective is to ensure adequate ventilation, oxygenation, and intravenous access. A multidisciplinary team will be activated to stabilize and control bleeding in life-threatening hemoptysis and admission to the intensive care unit. Intubation must not be delayed if a large-bore tube is not available. A chest x-ray should be the first imaging test performed. A multidetector computed tomography (CT) scan of the chest must be performed in stable patients. A flexible bronchoscopy is the diagnostic and treatment procedure of choice in unstable patients. A rigid bronchoscopy is only used when greater blood suction capacity and visualization of the airway is needed. Emergency surgery is reserved for failed bronchoscopy and embolization interventions.

Optimization Method of Jet Pump Process Parameters and Experimental Study on Optimal Parameter Combinations

The performance of jet pumps depends significantly on their structural and operational parameters. Current research primarily concentrates on theoretical models and laboratory tests, with limited experimental investigations and comprehensive reports concerning jet pump performance under various parameter combinations. In this study, we take a comprehensive approach, integrating both experimental and theoretical methods to assess jet pump performance under optimized process parameters and sand-flushing capabilities. The key findings of this study are as follows: While the characteristic and efficiency equations of jet pumps effectively describe the interaction of critical factors, including the area ratio, pressure ratio, flow rate ratio, and density, they unfortunately do not account for the influence of crucial structural factors, such as the nozzle throat distance, throat length, and diffuser length, on overall performance. Moreover, the parameter optimization technique based on the P-M curve has limitations and requires a tailored design and evaluation to consider the maximum suction capacity in practical engineering contexts. Notably, the nozzle throat distance significantly affects the jet pump suction capacity. Increasing the nozzle throat distance from 6 mm to 12 mm substantially enhances the suction capacity, albeit with a minor reduction in the lifting capacity. Extending the distance from 12 mm to 18 mm initially boosts the suction capacity, followed by a subsequent decline, along with a decrease in the lifting capacity. Interestingly, jet pumps effectively handle sand suction at relatively low pump pressures, creating negative-pressure conditions. As the pump pressure increases, the suction capacity remains relatively stable. However, the lifting capacity increases proportionally with the pump pressure, providing valuable theoretical and technical insights for practical jet pump applications. In summary, our study introduces a comprehensive approach to evaluate jet pumps by integrating experimental and theoretical methods. These insights highlight the intricate relationship between jet pump characteristics and operational parameters, offering essential knowledge for the efficient utilization of jet pumps in various applications.

Effect of working fluid temperature on energy dissipation characteristics of liquid ring vacuum pump

Liquid ring vacuum (LRV) pump working fluid temperature has a great influence on its energy efficiency. To improve the energy efficiency of the pump, a new model for the energy dissipation of the LRV pump was established based on the relationship between pump suction capacity, the vaporization loss rate of the working fluid and working fluid temperature. Furthermore, the theoretical model was experimentally verified and quantitatively analyzed. The results showed that the useless power increased and suction capacity decreased with increasing working fluid temperature. When the pump shaft speed was 1500r/min and the inlet pressure was 45kpa, the inlet liquid temperature increased from 15 °C to 45 °C, while the proportion of waste work dissipated by temperature rise of the working fluid significantly decreased from 78.8% to 22.1%. On the contrary, the proportion of the working fluid vaporization, the temperature rise of gas, and the convective heat transfer from the pump outer wall increased. The working fluid temperature positively correlated with the inlet fluid temperature and negative correlated with the inlet flow rate. To further reduce the pump operating temperature, it is necessary to increase the flow rate and reduce the inlet temperature.

PROTOTIPE ROBOT PEMBERSIH LANTAI BERBASIS MIKROKONTROLER

The development of automation has penetrated into all areas of life, including household appliances. One of them is robot technology for cleaning floors. With relatively small dimensions, this floor cleaning robot can reach under a table or bed. This floor cleaning robot is equipped with a microcontroller, suction pump and ultrasonic sensor to detect obstacles when scanning the floor surface. The microcontroller will process the ultrasonic sensor readings. If an obstacle is detected, the robot will avoid it by turning right or left. The suction pump is made of a 12 V DC motor with a suction power of 0.19 W for dust and 1.09 W for paper scraps. Based on the test results, this robot has a suction speed of 2.14 m/s and a suction capacity of 5.44x10-4 m3/s. With this floor cleaning robot, the job becomes lighter and easier.

Numerical Investigation on Pairing Solutions of Non-Positive Displacement Pumps and Internal Gear Pump for High-Speed Design

Raising the working speed of hydraulic pumps to maximize the efficient matching range of electric motors is one of the possible ways to achieve energy efficiency in electric machinery. By means of a simulation method verified with subsequent experiments in terms of filling efficiency, this paper first analyzed the suction capacity of crescent-type internal gear pumps with different geometric parameters at high speed, and the gear pair that is more suitable for high-speed operation was obtained. Subsequently, as the more significant contributions, two pairing solutions of a non-positive displacement pump and an internal gear pump were proposed to pressurize the inlet of the gear pump to keep it from cavitating. In the compact design solution, the inclined-holes type and axial-flow blade pumps share the same speed as the hydraulic pump, while the decentralized layout solution allows for flexible adjustment of the centrifugal impeller-type pump speed to maximize the filling capability. The final simulation results show that, with the help of inclined-holes type and centrifugal impeller type pumps, the filling efficiency of the internal gear pump at 6000 rpm can be improved by 3.59% and 5.84%, respectively, while the axial-flow blades pump fails to eliminate cavitation regardless of speed. Moreover, when the hydraulic pump works at 6000 rpm, the centrifugal impeller speed needs to be set above 2500 rpm to make sense.

P40 LIGHTS AND SHADOWS OF THE MICROCOAXIAL PUMP DEVICE IN A UNIQUE SETTING: CARDIOGENIC SHOCK DUE TO ACUTE MYOCARDIAL INFARCTION IN PATIENT WITH UNKNOWN HYPERTROPHIC CARDIOMYOPATHY

Abstract Cardiogenic shock remains the leading cause of death in patients with acute myocardial infarction (AMICS). The IntraAortic Balloon Pump (IABP) has been the device of first choice for these patients for years, but it has not shown a mortality benefit over optimal medical therapy. The Impella (AbioMed, Danvers, Massachusetts) is an alternative circulatory support system that produces cardiac output appropriate for the needs of the patient. A 59–year–old mailman suddenly lost consciousness during his work. Basic life support was administered, and ROSC was achieved after a single effective defibrillator discharge. When the ambulance arrived, the patient presented conscious but complained of oppressive chest pain, with soreness in his left arm and head. EKG showed an ST elevation in aVR and aVL and a right bandle branch block (Fig 1). Aspirin, Heparin, and opioids were administered. During the transport, hemodynamic parameters appeared to deteriorate towards cardiogenic shock. Coronary angiography showed a total occlusion of the left main. Cangrelor was started promptly. Hemodynamic conditions dictated the application of a mechanical circulatory support device (MCSD), so IABP was applied. Primary angioplasty was performed with restoration of TIMI 3 flow. A 3.50 x 23 mm everolimus–eluting stent was implanted with a good result. Norepinephrine was ineffective in achieving satisfactory hemodynamic status with systemic arterial pressure below 50 mmHg. After volemic restoration, neither IABP nor the vasopressor could interrupt the spiral of cardiogenic shock. A coaxial pump, i.e. the Impella CP, was applied via left arterial femoral access. Despite the precise placement of this device, the parameters suggested a poor suction capacity from the pump–inlet into the left ventricle (LV) to systemic circulation in aorta. Meanwhile, echocardiogram revealed an unknown and severe hypertrophic cardiomyopathy that did not allow a proper functioning of the Impella CP device (Fig. 2). When a temporary pacemaker was applied due to reperfusion bradycardia, there were a better LV diastolic filling and Impella functioning due to right pacing. The patient was transferred to the intensive care unit, Impella was removed after 3 days, he was extubated within two weeks, no brain damage was reported but he is still hospitalised after a concomitant urinary infection, with predictable low ejection fraction (around 30%). We‘ll see: luckily, slow improvement, it is still an improvement!

Optimization of Flow and Mixing in a Venturi Tube Mixer with a Two-Step Method Using Numerical Simulation

To achieve efficient mixing in a Venturi tube mixer (VTM), an optimization with a two-step method for this mixing device based on a Venturi tube (VT) was carried out using numerical simulation. Firstly, the effects of the structural parameters on the flow in VT were revealed, and the optimized configuration was determined for the following VTM. Subsequently, by introducing a jetting tube, the suction capacity, energy consumption and mixing quality were used to evaluate the performance of VTM under various configurations and operating conditions. According to the effects of the structural parameters on the mixing quality of VTM, an empirical formula for mixing quality with structural parameters was proposed. Finally, an optimized VTM was proposed. This work can provide a valid suggestion for the design and optimization of such a mixing device.

Study on Flame Suction Behavior of High-Pressure Gas Well under Self-Excited Negative Pressure Effect

Summary Placing a flow tube on the wellhead to suction flame during a well control operation is key to creating a safe environment near the wellhead. Aiming at the problem that the internal flame of the flow tube can easily leak during the rescue of a high-pressure gas well, we propose in this paper to use the self-excited negative pressure effect to improve the capacity to suction flame. Based on the coupling method of the Reynolds averaged Navier-Stokes equation and mixed combustion model, a gas well combustion model is established. The accuracy of the model is verified by proportional scaling experiment. Furthermore, the sensitivity analysis of key structural parameters of self-excited negative pressure flow tube is carried out, and the structure of the flow tube optimized. The result shows that the optimized flow tube has a suction flow about twice that of the horn flow tube, and the suction scope is increased by 61.5%, which greatly improves the flame suction capacity. The research work can provide guidance for structural design and optimization under self-excited negative pressure effect.

Preparation and evaluation of aldehyde starch hemostatic microspheres crosslinked with L‐cystine dimethyl ester for ultrarapid rapid hemostasis

AbstractRapid hemostasis, biosafety, and adaptability to different bleeding sites are the focus of research on hemostatic materials. In this work, an efficient and simple preparation of aldehyde starch hemostatic microspheres (ASHMs) crosslinked with L‐cystine dimethyl ester was developed. Through a series of physicochemical parameters and in vitro and in vivo hemostatic properties measurements, the results showed that under the optimal crosslinking degree, ASHMs had a regular and uniform spherical shape, and it had a liquid suction capacity of up to 880%. At the same time, the aldehyde groups on its surface can increase the adhesion and aggregation of blood cells, thereby enhancing the hemostatic effect, which can be considered as a synergistic effect. More importantly, ASHMs have good biocompatibility and minimal intradermal irritation. Taken together，ASHMs could be used as potential novel hemostatic materials for surgical treatment.

Research on hydraulic loss of liquid ring vacuum pump and optimization of shell profile for high efficiency and energy saving

The shell profile of liquid ring vacuum pump has an important influence on the flow channel, the gas-liquid two-phase flow distribution and the working efficiency of liquid ring vacuum pump. Firstly, the hydraulic loss theoretical model of the liquid ring vacuum pump is developed, and the mechanism of hydraulic loss is revealed. Then the scale and distribution of hydraulic loss are studied based on entropy production theory. The results indicate that the direct dissipative entropy production, the turbulent dissipative entropy production and the wall effect entropy production account for 39.85%, 20.24% and 39.91% of total entropy production respectively. Secondly, a high-efficiency and energy saving design method for the shell profile of liquid ring vacuum pump is studied, and the parametric control model for shell profile is proposed based on the direct free form deformation algorithm. The optimized shell profile for maximum suction capacity can achieve the suction capacity increase of 45.7% and isothermal compression efficiency increase of 8.1%, while the optimized shell profile for minimum wall effect entropy production can achieve the wall effect entropy production decrease of 18.7% and specific power decrease of 11.6%. Finally, the multi-objective optimization design is carried out with the elitist nondominated sorting genetic algorithm.

Experimental and numerical analysis for improving the suction capacity of the manufactured water jet ejectors

Water jet ejectors are the silent pumping fluid devices which doesn’t have any rotating parts in functional industrial applications. The dimensionless geometrical parameters effects ejector suction capacity. In this study, it is found that optimum design intervals have been determined by using the Response Surface Method (RSM). Design ranges determined in the dimensionless study have been used in the improvement of the suction capacity of an existing ejector. The suction capacity of the existing ejector is investigated via numerical and experimental analysis. Two new water jet ejector designs (D1 and D2) are built to improve the suction capacity of the initial water jet ejector (D0). The generated design parameters have been analyzed by using SolidWorks flow analysis and optimization software. The suction capacity of the ejector has been determined through the iterative numerical analysis for the selected geometrical parameters under the applied design conditions. The effect of design parameters on the suction capacity of the water jet ejectors is unveiled through numerical and experimental analysis. The established designs were produced as two novel bronze water jet ejectors. The suction capacities of the produced bronze water jet ejectors have been investigated experimentally. The numerical results have been validated using the experimental results. It is achieved that the suction capacity of the manufactured water jet ejector with the improved design (D2) is suddenly increased from 52.05 m3/h to 103.4 m3/h.

THE LYMPHATIC SYSTEM – A NEW LOOK AT OLD PROBLEMS

The lack of adequate methods for the simultaneous detection of lymphatic and blood microvessels in hollow organs does not make it possible to determine the morphological basis of lymph formation and lymph dynamics. In the relevant scientific literature, information about of the structural organization of the lymphatic system, obtained using transmission and scanning electron microscopy, does not provide exhaustive answers to the currently controversial and unresolved issues of the structural organization of the lymphatic microcirculatory bed. The purpose of the study is to presenting data on the organization of the initial lymphatic channel, obtained on the basis of the use of original impregnation methods. Studies were conducted on cats (n=17) and dogs (n=11). The microvascular bed of the intestine and epicardium was identified along with the surrounding tissues by impregnation. On histological preparations, endothelial trabeculae were identified in the lumen of non-muscular lymphatic microvessels of different diameters in the muscular layer and in the submucosa of the intestine. In the muscular layer of the intestinal wall, numerous interstitial channels were found that communicated with open lymphatic capillaries. In the submucosa of the intestinal wall of experimental animals, in addition to the classic capillaries that begin closedly, previously unknown structures were identified - open perivasal lymphatic microvessels and open lymphatic capillaries flowing into them. In the lumen of the perivasal lymphatics are arterioles or arteries. Lymphatic capillaries were in various functional states, which indicates their active peristalsis and suction capacity, which characterize them as utilizers of «biological debris». As a result of the conducted studies, new objective data on the structural organization of the initial lymphatic bed in hollow organs were obtained. The authors showed that the vasomotor activity of the initial lymphatics can serve as a morphological basis for the hypothesis of the initial lymphatic cycle, which consists of a resorption phase and an expulsion phase. The hydrostatic pressure drops in the lumen arising from such a two-phase vasomotor activity of the lymphatics indicate their important role in the process of lymph formation and lymph circulation.

Preparation and performance of a self-humidifying fuel cell using a fiber sintered sheet as flow field

The water management problem of fuel cells has been troubled for its further application, and the precision of the existing humidity control strategy is not sufficient to adapt to complex operating conditions. In this study, a new type of porous flow field, based on metal fibers with continuous capillary paths and excellent capillary suction ability, is proposed to retain moisture and enhance the back diffusion of moisture from the cathode to the anode, to achieve self-humidification. These fibers are obtained by turning, and their surface is covered with multi-level microstructure, which greatly increases specific surface area, and the capillary suction capacity of the fibers for water, compared to the ordinary smooth surface structure. Experimental results show that the fiber flow field with an optimal porosity of 70% can operate stably at 50 °C and achieve the best performance when humidified at room temperature. Under atmospheric pressure, the temperature resistance is increased by 5 °C compared to the serpentine flow field, and the limit peak power density is increased by 18.75%.