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The pump head of the hydraulic diaphragm pump is a key component of the metering pump, which has a large impact on the metering accuracy and reliability and affects the normal operation of medium transportation and safe production. Based on CFD method, the dynamic mesh model provided by software FLUENT is applied for dynamic numerical simulation of the three-dimensional flow field of the diaphragm pump and to establish the calculation model for the motion law of the ball valve of the reciprocating pump. Through visual tests and measurements of the ball valve motions, the simulation and measurement results under the same condition are compared, and the two are basically consistent. Combined with the measurement of fluid pressure fluctuation in the pump and valve, the pressure fluctuation caused by the ball valve motions is analyzed, and the influence of speed ratio, stroke and medium viscosity on ball valve lift is deduced, which provides a reference for the design and selection of ball valves for the pump head. [ABSTRACT FROM AUTHOR]

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V okviru zaključne naloge smo obravnavali delovanje centrifugalnih vodnih črpalk v okviru laboratorijske merilne postaje na Fakulteti za strojništvo, ki omogoča analizo delovanja črpalk v različnih režimih delovanja. Glavni cilj je bil obnoviti in nadgraditi merilno postajo ter vzpostaviti merilni sistem za zajem obratovalnih veličin in analizo karakteristik. Prvi del naloge je bil zato usmerjen v analizo trenutnega stanja. Glede na dotrajanost določenih delov merilne postaje smo izvedli zamenjavo regulacijskega ventila in nadgradili sistem za zajem in obdelavo izmerjenih veličin. V programskem okolju LabView smo vzpostavili okolje za zajem in obdelavo podatkov ter analizo karakteristik črpalk in cevovoda. V drugem delu naloge smo izvedli preizkuse ob različnih vezavah ene in/ali dveh centrifugalnih črpalk. Na podlagi meritev smo izračunali volumski pretok, dobavno višino, izkoristek in teoretično moč. Izrisali smo graf odvisnosti dobavne višine od pretoka, kar predstavlja osnovno karakteristiko centrifugalne črpalke. Na podlagi izmerjene potrebne električne moči smo dodatno, v vseh obratovalnih točkah izračunali energijski izkoristek centrifugalnih črpalk. Na podlagi dobljenih rezultatov lahko zaključimo, da je bila nadgradnja merilne postaje uspešna, saj nadgrajeni merilni sistem deluje pravilno, rezultati pa so v okviru pričakovanih vrednosti. The final thesis looked at the performance of centrifugal water pumps in the context of a laboratory metering station, which allows the analysis of the performance of pumps in different operating regimes. The main objective was to refurbish and upgrade the measurement station and to set up a measurement system for the acquisition of operating quantities and the analysis of the characteristics. The first part of the task focused on the analysis of the current situation. The control valve was replaced and the system for the acquisition and processing of measured values was upgraded. In the LabView software environment, we set up an environment for data acquisition and processing, as well as for the analysis of the pump and pipeline characteristics. In the second part of the task, tests were carried out with different couplings of one and/or two centrifugal pumps. Based on the measurements, we calculated the volumetric flow rate, delivery height, efficiency, and the theoretical power. We have plotted a graph of the dependence of the delivery head on the volumetric flow, which represents the basic characteristic of a centrifugal pump. Additionally, the energy efficiency of the centrifugal pumps has been calculated at all operating points based on the measured electrical power required. Based on the results, it can be concluded that the upgrade of the metering station has been successful, as the upgraded metering system is working correctly, and the results are within the expected values.

The paper describes the model of the centrifugal pump head curve obtaining process which helps in consideration of the implementation of automated systems in liquid-propellant rocket engine manufacturing. The work contains the simulation of automated and non-automated head curve obtaining. The developed model shows that the automated process exceeds the non-automated analog in terms of error values and labor intensity

Multiphase pump is widely applied for the exploitation of oil-gas resources in off-shore platforms. It is essential to investigate the performance of multiphase pumps when handling high viscosity fluid. A three-stage helico-axial multiphase pump with working fluids under various viscosities is investigated in the present study. Both energy performance and flow fields have been discussed with different viscosities. The influences of viscosity, flow rate and blade height on the distribution of turbulence kinetic energy are analyzed. Results show that both pump head and efficiency gradually reduce with the rise of viscosity when handling high viscosity fluid. The rise of viscosity and blade height, and the decline of flow rate will lead to an increase of turbulence kinetic energy. Characteristics of partial differential equations are employed to reveal the influence of viscosity, and a theoretical model has been established to predict the influence of flow rate.

The ability of a pump to drain or move a certain amount of fluida / fluida that comes out through the pressure side of the pump in units of time volume is also called the capacity of a pump . Meanwhile, the pump head is the energy per unit weight that must be provided to flow the planned amount of liquid according to the pump installation conditions. A centrifugal pump is a pump that moves liquid by utilizing the centrifugal force generated by the impeller ratation. The results of data calculations and graphic analysis on the effect of variations in the impeller entry angle on the impeller with exit angle (β2) = 250,standard pump impeller,and impeller with exit angle (β2) = 350 on the performance of the centrifugal pump can be concluded, namely “the performance value of centrifugal pumps. The highest is the impeller with exit angle (β2) = 250 where the specific speed value produced is 192.52 rpm and the efficiency level of this impeller is 6.82%

The article presents a method for calculating the efforts on the bearings and the shaft of a soil axial pump located on the frame of a dredger suction device. The article considers the abrasive wear of the impeller during operation, which increases the centrifugal force and causes increased shaft bending, as well as the axial force on the pump impeller created by the pump head and the components of the weight of the shaft and impeller when the frame is tilted.

The presence of formation water throughout the oil well production lifetime is inevitable and consequently forming the dispersion or the emulsion due to the immiscibility of those two phases and the strong shear force acting in a rotating ESP. The formation of stable emulsion close to the inversion point will significantly increase the effective viscosity of an emulsion. This paper will present an experimental investigation of emulsion rheology inside the ESP and its effect on ESP performance under various oil viscosities and different water cuts (WC).Multi stages radial type ESP were assembled into a viscous flow loop which was initially developed by Zhang (2017). Emulsions at each WC formed from different oil viscosities, similar oil density, and surface tension. Multistage ESP was used to circulate oil/water emulsions in a close flow loop. Mass flowmeter measures both mass flow rate and fluid density, and the effective emulsion viscosity derived from an in-line pipe viscometer (PV) which locates downstream of the ESP discharge. The pressure transmitter is occupied in each pump stage to measure the pressure increment. The experiment results present in terms of pump boosting pressure at each water cut and the flow rate delivered by the pump.A Single-phase oil experiment was run at a different temperature to validate the accuracy of the PV. The data discrepancy of PV's viscosity and rotational viscometer is ±6%. The experiment results captured the emulsion's effective viscosity trend as a function of WC. A significant increase of effective viscosity close to the inversion point was observed, and it occurs due to a higher number of water droplets and hydrogen bonds which lead to an increase in hydrodynamic forces thus generating a tight emulsion. The experiment results reveal that a higher oil viscosity 70 cp reaches an inversion point at 30% - 35% WC. Meanwhile, for lower oil viscosity 45 cp reaches the inversion point at 35% - 40% WC since the turbulence increases with the decrease of oil viscosity. The increasing of effective viscosity in the water-oil emulsion induces higher pressure loss in the pump due to high friction loss, and it deteriorates the pump head. Nevertheless, as the WC increases further, the pump head will advance close to the single-phase water performance since the water turns as the continuous phase. Eventually, we can observe a prudent relationship in the pump performance in the change of emulsions effective viscosity as a function of WC. The inversion point phenomena occur at a different range of WC for different oil viscosity. Therefore, it is vital to set the possible range of operational conditions away from the inversion point. A better understanding of these aforementioned issues will lead to an accurate ESP design for optimum well performance.

Goal: The importance of the main impeller design parameters in bearingless centrifugal pumps with respect to hemolysis for cardiopulmonary bypass (CPB) and extracorporeal membrane oxygenation (ECMO) applications are studied in this work. Methods: Impeller prototypes were designed based on theoretical principles. They were manufactured and their hydraulic and hemolytic performance were analyzed experimentally. The cell compatibility is benchmarked against commercially available centrifugal blood pumps BPX-80 (Medtronic) and FloPump 32 (International Biophysics Corporation). Results: The developed prototypes outperform the BPX-80 and FloPump 32 with regard to hemocompatibility by more than a factor of 4.5. The implemented pump features reduced overall and priming volumes. A significant improvement of the cell compatibility is achieved by increasing the radial gap between the impeller and the pump head. The blade should be sufficiently high and a blade outlet angle of 90° provides favorable performance. No correlation between the hydraulic and hemolytic performance is observed. Conclusions: This work identified the most important geometrical parameters of the impeller for blood pumps with respect to cell compatibility. This provides valuable design guidelines for improving existing pumps., IEEE Open Journal of Engineering in Medicine and Biology, 1, ISSN:2644-1276

Purpose The purpose of this paper is to investigate the clocking effect of impellers and the superposition between pump stages caused by clocking effect in a five-stage centrifugal pump. Then the best clocking scheme in terms of vibration is tried to be provided as well. Design/methodology/approach All curves of pressure fluctuation in different impeller stages can be divided into two groups for the difference of 1/16 T in time domain. The difference is mostly in vibration frequency and amplitude, little in pump head and efficiency. Findings All curves of pressure fluctuation in different impeller stages can be divided into two groups for the difference of 1/16 T in time domain. The difference is mostly in vibration frequency and amplitude, little in pump head and efficiency. Research limitations/implications This research involves eight different impeller clocking schemes. The results show that the clocking effect has little influence in pump head and efficiency, but the influence in pressure fluctuation is larger. Practical implications The paper provides guidance for the design of multistage pump for better vibration performance. Originality/value This research involves eight different impeller clocking schemes, the results show that the clocking effect has little influence in pump head and efficiency, but the influence in pressure fluctuation is larger. Then the best clocking scheme In terms of vibration is tried to be provided through analysis.

Santrifüj su pompaları temiz su iletmeleri durumunda verimli bir şekilde kullanılabilirken, katı-sıvı karışımlı (çamur) atık su iletmeleri söz konusu olduğunda ise çark kanallarının dar olması nedeniyle tıkanmalar sonucu sıklıkla arızalanmaktadır. Dalgıç tipi parçalayıcı bıçaklı atık su drenaj pompaları katı, lifli ve partikül içeren akış şartlarında kullanılmak için geliştirilen yeni bir tasarım olup daha uzun ömürlü olması beklenen bir pompa türüdür. Bu pompanın çark ve emiş ağzına takılan kesici uçlarla, birçok katı partikül öğütülerek tahliye edilir. Bu durum pompaya ilave güç bindirmekte ve basma yüksekliğini düşürmektedir. Bu çalışmada, iki farklı sanrfifüj tipli parçalayıcı bıçaklı atık su drenaj pompasının basma yükseklikleri temiz su kullanılması durumunda incelenerek sonuçları karşılaştırılmıştır. Yapılan test çalışmalarına göre, ithal pompanın düşük debilerde daha yüksek basma yüksekliğine sahip iken, artan debilerde ise imalatı yapılan firma pompasının daha iyi performans sergilediği görülmüştür., Centrifugal water pumps can be used efficiently when they deliver clean water, in the case of solid-liquid wastewater or slurry transmissions, they often fail as a result of blockages due to narrow impeller channels. Submersible type wastewater drainage pumps with cutter blades are a new design developed for use in flow conditions containing solid, fibrous, and particulate matter and are expected to have a longer life. Many solid particles are grinded and discharged with the use of cutter blades attached to its impeller and suction side of the volute. These attachments cause additional load on the pump shaft, reducing pump head. In this study, the performances of two different centrifugal type submersible cutter pumps were examined and compared in case of using clean water. According to the test studies, it has observed that the imported pump has a higher head at low flow rates, while the company-produced pump has performed better in increasing flow rates.

Impeller is an important part of the axial flow pump. Basing on main characteristics of the pump as pump head, flow rate and efficiency, impeller blades are designed with free form surface to meet requirements of hydrodynamical functions. The paper presents a complete process from designing an impeller blade by Vozexexki - Pekin method, modeling the blade by Solidwork to manufacturing it by 3 axes CNC milling. Through an empirical research for assessing influence levels of three factors as tool path type, side step, diameter of tool on the geometrical accuracy of the free - surface forming of the impeller blade, the authors have selected appropriate technological parameters to machine the blade surface. By the technological parameters, the impeller blade was completely machined by 3 axes CNC milling.

SUMMARYElectronic cigarettes (ECs) have been linked to lung diseases, including COVID-19, with little understanding of exposure, retention, and exhalation of EC aerosol chemicals. Here, flavor chemicals and nicotine were quantified in two refill fluids, their transfer efficiency to EC aerosols was determined, exhalation by human participants was measured, and chemical retention was modeled. Nicotine transferred well to aerosols irrespective of topography; however, transfer efficiencies of flavor chemicals depended on the chemical, puff volume, puff duration, pump head, and EC power. Participants could be classified as “mouth inhalers” or “lung inhalers” based on their retention and exhale of flavor chemicals and nicotine. Only mouth inhalers exhaled sufficient concentrations of flavor chemicals and nicotine to contribute to chemical deposition on environmental surfaces. These data help distinguish two types of EC users, add to our knowledge of chemical exposure during vaping, and provide information useful in treating EC-related diseases and regulating EC use.

The combined pump and hydraulic ram pump (HRP) was presented to evaluate the technical feasibility for increasing pump head. This method was used to demonstrate a possible low‐cost alternative solution to supply water in remote areas. It illustrated the case where energy in rivers was not enough to drive HRP and a pump alone could not lift water to the required head. The HRP was connected in series with the pump. The experiment on the combined system operation was investigated. The system was working only at a certain range of flow rates for a power supply by the pump. Therefore, HRP was adjusted to pump water in the range that the waste valve was functioning. The combined system can operate at a low flow rate with a high head without extra energy and no overloading. It reveals that the more discharge head is required, the less flow can be lifted which results in a high number of valve beats per minute of the waste valve. Experimental determination of the optimal values for these parameters will make it possible to provide for a feasible design of HRP in the given pump. The optimal HRP will make it possible to ensure the required performance (delivery, head, efficiency) of the combined system.

A novel centrifugal pump with axial directional inlet and outlet flow was presented. The system fluid was employed as the lubricant for the hydrodynamic bearings by which the pump can operate at the maximum speed of 8100 r/min without oil lubrication or rigid support. The performance curves related to the efficiency, head, and volume flow rate were obtained via a water cycle test rig. The efficiency at best efficiency point reached 36.14% with a volume flow rate of 4.13 m3/h and a head of 27.34 m at 7800 r/min. The maximum head reached 37.28 m, with a volume flow rate of 0.568 m3/h at 7800 r/min. The maximum volume flow rate of 6.05 m3/h was obtained with a head of 19.45 m at 8100 r/min. Then, the three-dimension computational fluid dynamics model with Reynolds-averaged Navier–Stokes equations and shear stress transport k- ω turbulence model for the pump and bearings was set up individually. The numerical results agreed well with the experimental data.

The water flow rate through a pump can be calculated using other measured inputs, such as pump head, motor input power, and frequency, along with calibrated characteristic curves. Currently virtual...

Hydrodynamics of flow of a solution in a membrane channel were investigated and a criterion equation was obtained to determine the structural coefficients of flow. A method was developed that takes into account the hydrodynamics of flow, which allows to determine the technological parameters of the membrane installation. A quantitative calculation was performed to determine the working area, the number of elements, pressure losses and pump head for roll-type elements ERO-e-6.5/900А and ERO-K-92-475 in reverse osmosis separation of different industrial solutions.

The research focuses on determination of best location of high elevated tank using the required head of pump as a measure for this purpose. Five types of network were used to find the effect of the variation in the discharge and the node elevation on the best location. The most weakness point was determined for each network. Preliminary tank locations were chosen for test along the primary pipe with same interval distance. For each location, the water elevation in tank and pump head was calculated at each hour depending on the pump head that required to achieve the minimum pressure at the most weakness point. Then, the sum of pump heads through the day was determined. The results proved that there is a most economical location where the energy consumption is minimum. This location joined with the branched line that containing the most weakness point. The best location didn’t join with the highest demand location unless this location containing the most weakness point. The results indicated that the moving of tank away from best location in pump direction result in pump head increasing that exceed the increasing in pump head when the tank moves in the opposite direction. The location of tank beside the pump station was the worst location. Also, the results showed that as the distance between the pump and the highest demand become shorter, the required pump head become less. The uniform demand distribution required the least amount of pump head, it required minimum head of (554)m while the networks, that have highest demand at distance 200m,400m, and 1000m from the pump station, required minimum head of 651m, 682m, and 726m respectively.

Recently, a fully magnetically levitated left ventricular assist device (LVAD) system (HeartMate 3, Thoratec, Pleasanton, California) has become clinically available [(1)][1]. The centrifugal rotor of the pump head in this system allows large flow gaps around it. Due to an artificial pulse algorithm

The AFE System is a medical device intended to dilate the cephalic vein by increasing the blood flow and wall shear stress (WSS) in the vein over a period of 10-14 days prior to creation of an arteriovenous fistula (AVF) for haemodialysis; the system functions as a means of increasing eligibility for AVF surgery and reducing rates of AVF failure. During treatment, maintaining WSS around 4 Pa in the treated vein is desirable to provide optimal vein wall stimulation while avoiding wall injury that could lead to venous stenosis. Developing a model of the AFE System and the related venous circulation could help design a control system for maintaining WSS in the treated vein during the period of treatment when the vein is increasing in diameter. Using a broad application of the Hagen-Poiseuille law, WSS calculation could be based on differential pressure and the flow rate. The AFE System pump was characterised in a test rig utilising sensors and a data acquisition system for measuring mechanical parameters. A data-based model of the AFE pump which includes pump head estimation based on flow rate or electrical current, and motor speed measurements has been developed, and is presented in this paper. All data fitted the developed relationships well, with a correlation coefficient of 93% or above.

The paper presents the results of experimental studies into the dependences of the axial pump performance (delivery rate, head, efficiency) in lead coolant on the parameters of the straightening device (SD) installed downstream of the impeller (the SD inlet flow angle and the number of the SD blades with a variable impeller speed change). The studies were performed as applied to the operating conditions of small and medium plants with lead cooled fast neutron reactors with horizontal steam generators (BRS GPG). The designs of such plants are being matured at Nizhny Novgorod State Technical University (NNSTU). The experiments were conducted on the FT-4 NGTU test bench at the lead coolant temperatures in a range of 440 to 500 °C. The number of the test blades was five and eight, and the SD inlet flow angle was 22, 24, 28, and 32°. The tests were also performed without an SD (with the SD dismantled). The shaft speed of the NSO-01 NGTU pump, with changeable SDs installed into its rotating assembly, was varied in a range of 600 to 1100 rev/min with a step of 100 rev/min. The SD sleeve diameter was 82 mm, the SD blade diameter and height were 213 mm and 80 mm respectively, and the maximum lead coolant flow rate during the studies was up to ~ 1650 t/h. The NSO-01 NGTU pump performance was determined with four changeable straightening devices and with no SD, the pump shaft speed being 600 to 1100 rev/min, as the circulation circuit hydraulic resistance changed owing to the movement of the wedge in the valve installed in it. The tests were performed with the impeller designed and supplied by NNSTU (D = 213 mm, dsl = 82 mm, the blade number is four, and the blade angle is 28°). The obtained results are recommended for use to design axial heavy liquid metal coolant pumps.