Pump Performance Parameters Research Articles

Water pump flow monitoring method for air conditioning system based on parameter model

The widespread development and application of virtual sensors in buildings will play an important role in promoting industry change and achieving smart buildings. In this study, a virtual monitoring method of pump flow rate was developed and verified. First, the pump flow parameter model was constructed based on pump operating parameters. Then, the calibration process of the model and the identification process of the pump-related efficiency were given. Finally, the experimental platform and the actual project were used to verify the virtual monitoring method of pump flow. The results showed that for the experimental test, the mean relative errors (MREs) of the three proposed methods are less than 1.79 %; for the actual project, the MREs are less than 2.48 %. Compared with existing methods, the prediction accuracies of the proposed methods have been significantly improved, and the methods are suitable for different application scenarios of pumps (with and without VFDs installed). Meanwhile, the parameters required for model calibration of proposed methods are easier to obtain. The introduction of proposed virtual monitoring methods will contribute to the replacement or backup of existing flow meters, efficiency analysis of pump systems, system fault detection and optimization control, and implementation of smart building systems.

Effects of Tubing Type, Operating Parameters, and Surfactants on Particle Formation During Peristaltic Filling Pump Processing of a mAb Formulation

Filling pump operation is an important cause of particle formation in therapeutic protein formulations. The goals of the present study were to investigate the impacts of peristaltic filling pump tubing type, pump operating parameters (acceleration and velocity), and formulation on both nanoparticle and microparticle formation in water, placebo, and a 120 mg/mL mAb drug formulation. Microparticles were quantified using flow imaging microscopy and light obscuration, and nanoparticles were counted with nanoparticle tracking analysis. Pumping of all solutions through Pharmed® tubing resulted in much higher particle levels than processing with Accusil™ or Masterflex® tubing. Pump acceleration did not measurably affect particle levels in pumped solutions, but in some cases, a relatively high pumping velocity of 400 rpm enhanced nanoparticle formation. The presence of surfactants reduced pumping-induced particle formation in the mAb solution, and the effects of 4 different surfactants tested were similar. Biophysical properties (secondary and tertiary structure, and thermal stability) of the protein in solution were not altered by pumping. Overall, this study demonstrates that investigations of pumping parameters and formulations using both nanoparticle and microparticle measurement methods are important for understanding pumping-induced particle formation and developing effective control strategies.

Visualization of two-phase gas-liquid flow in a radial centrifugal pump with a vaned diffuser

The operation of centrifugal pumps with gas-liquid mixtures is a common problem in the oil and gas industry. The main problem is related to the accumulation of gas inside the Electric Submersible Pump (ESP) impellers, which causes degradation of the pump pressure-rise. Literature about global performance parameters of centrifugal pumps operating with gas-liquid flows is limited, and studies focused on understanding the complex flow patterns occurring inside impellers are even scarcer. In this scenario, this work presents an experimental work developed to carry out, simultaneously, head evaluation and high-speed flow visualization in a two-stage centrifugal pump with radial-type impellers and a vaned diffuser. The pump casing and the first stage impeller were replaced by equivalent pieces reproduced with great fidelity using a transparent material in order to allow flow visualization while minimizing the effect of non-original pump parts on performance. Results show flow pattern transitions in the impeller channels when the rotating speed, the inlet gas flow rate and the liquid flow rate are changed, whereas only a single flow pattern was observed in the diffuser for the whole range of tested operating conditions. In addition, increasing the rotating speed causes, in general, a decrease of the bubble diameters inside the impeller, improving the pump's ability to handle higher gas flow rates and ultimately extending the operational window of the pump. This analysis can provide a source of data that can be useful to support theoretical models or to validate numerical simulations.

Numerical and Experimental Investigation on Radiated Noise Characteristics of the Multistage Centrifugal Pump

The radiated noise of the centrifugal pump acts as a disturbance in many applications. The radiated noise is closely related to the hydraulic design. The hydraulic parameters in the multistage pump are complex and the flow interaction among different stages is very strong, which in turn causes vibration and noise problems because of the strong hydraulic excitation. Hence, the mechanism of radiated noise and its relationship with hydraulics must be studied clearly. In order to find the regular pattern of the radiated noise at different operational conditions, a hybrid numerical method was proposed to obtain the flow-induced noise source based on Lighthill acoustic analogy theory, which divided the computational process into two parts: computational fluid dynamics (CFD) and computational acoustics (CA). The unsteady flow field was solved by detached eddy simulation using the commercial CFD code. The detailed flow information near the surface of the vane diffusers and the calculated flow-induced noise source was extracted as the hydraulic exciting force, both of which were used as acoustic sources for radiated noise simulation. The acoustic simulation employed the finite element method code to get the sound pressure level (SPL), frequency response, directivity, et al. results. The experiment was performed inside a semi-anechoic room with a closed type pump test rig. The pump performance and acoustic parameters of the multistage pump at different flow rates were gathered to verify the numerical methods. The computational and experimental results both reveal that the radiated noise exhibits a typical dipole characteristic behavior and its directivity varies with the flowrate. In addition, the sound pressure level (SPL) of the radiated noise fluctuates with the increment of the flow rate and the lowest SPL is generated at 0.8Qd, which corresponds to the maximum efficiency working conditions. Furthermore, the experiment detects that the sound pressure level of the radiated noise in the multistage pump rises linearly with the increase of the rotational speed. Finally, an example of a low noise pump design is processed based on the obtained noise characteristics.

The Influence of Changing Hydropower Potential on Performance Parameters of Pumps in Turbine Mode

Pumps as turbines (PAT) are used as an alternative to water turbines in small hydropower plants. The same devices can also be used for energy recovery in water distribution networks. They can replace pressure reduction valves that often lead to energy loss. However, PATs lack the parts that regulate flow so that when a hydropower potential change occurs, efficiency is reduced, as is economic gain. This article summarizes the influence of changing hydropower potential on PAT efficiency and presents comparisons of experimental results with the commonly used predictive model stemming from the theory of physical similarity, which presumes constant PAT efficiency. Our research indicates that the deviation between the model and the real power output calculation at varying potentials was minimal. Similarly, the affine parabola can be used to determine the relationship between total head and flow rate. Other relationships differ from reality the more the PAT efficiency changes. The flow rate and total head dependence on shaft speed are the main factors when setting the optimum operational parameters at varying hydropower potentials. Therefore, a change in efficiency must be included in predictive calculations to correctly optimize PAT operation. The problem is that a change in efficiency cannot be reliably predicted in advance, especially in the case of small-scale devices. For this reason, further research on the issue of changes in PAT efficiency is necessary.

Fluid characteristic of multiphase fluid in annular space between pump barrel and plunger

The pump performance parameters, such as pump pressure, plunger friction and pump valve resistance, are fundamental parameters of optimal design of pump efficiency and sucker rod pumping system (SRPS). In this paper, considering the characteristic of geometrical nonlinear and rheology property of multiphase fluid, the pump performance parameters are studied. Firstly, a dynamics model of annular fluid flow is built. In the detail, a partial differential equation of annular fluid is established and a computing model of fluid pressure gradient is built. Secondly, the simulation models of plunger friction and hydraulic resistance of pump valve are built. Finally, a novel simulation method of fluid pressure in annular space is proposed with software ANSYS. In order to check up the correction of models proposed in this paper, the comparison curves of experiment and simulation results are given. Based on above model, the whole simulation model of plunger pump is simulated with Visual Basic 6.0. The results show that the fluid friction of pump plunger and instantaneous resistance of pump valve are nonlinear. The impact factors of pump performance parameters are analyzed, and their characteristic curves are given, which can help to optimize the pump motion parameters and pump structural.

Computer Simulation of Crude Oil Extraction Using a Sucker Rod Pumping Unit in the Oil Well–Resevoir System

The process of operating volatile oil wells using the sucker rod pumping method is considered. An algorithm is developed to determine the main characteristics of the development of deposits in the oil well–reservoir system and the parameters of sucker rod pumping unit. The real thermodynamic properties of volatile oil and the compressibility of the reservoir are taken into consideration. Based on the proposed algorithm, a computer model of the oil well operating process by a sucker rod pump is developed. This model makes it possible to monitor the main operating parameters of the pump and the characteristics of the reservoir system. The development of the reservoir and the effect of the pump operating parameters on its productivity are studied using the developed simulator. The influence of pumping rate on the pump performance is established to be insignificant if a certain value is exceeded. The proposed algorithm can be used to create intelligent systems for automated control of sucker rod pumps in the well–reservoir system.

Effect of Evaporator Load on Heat Pump Operating Parameters and Performance

Effect of Evaporator Load on Heat Pump Operating Parameters and Performance

Early in vivo experience with the pediatric continuous-flow total artificial heart.

Heart transplantation in infants and children is an accepted therapy for end-stage heart failure, but donor organ availability is low and always uncertain. Mechanical circulatory support is another standard option, but there is a lack of intracorporeal devices due to size and functional range. The purpose of this study was to evaluate the in vivo performance of our initial prototype of a pediatric continuous-flow total artificial heart (P-CFTAH), comprising a dual pump with one motor and one rotating assembly, supported by a hydrodynamic bearing. In acute studies, the P-CFTAH was implanted in 4 lambs (average weight: 28.7 ± 2.3 kg) via a median sternotomy under cardiopulmonary bypass. Pulmonary and systemic pump performance parameters were recorded. The experiments showed good anatomical fit and easy implantation, with an average aortic cross-clamp time of 98 ± 18 minutes. Baseline hemodynamics were stable in all 4 animals (pump speed: 3.4 ± 0.2 krpm; pump flow: 2.1 ± 0.9 liters/min; power: 3.0 ± 0.8 W; arterial pressure: 68 ± 10 mm Hg; left and right atrial pressures: 6 ± 1 mm Hg, for both). Any differences between left and right atrial pressures were maintained within the intended limit of ±5 mm Hg over a wide range of ratios of systemic-to-pulmonary vascular resistance (0.7 to 12), with and without pump-speed modulation. Pump-speed modulation was successfully performed to create arterial pulsation. This initial P-CFTAH prototype met the proposed requirements for self-regulation, performance, and pulse modulation.

Hydraulic characteristics of molten salt pump transporting solid-liquid two-phase medium

In this study, a three-dimensional solid-liquid two-phase flow in a molten salt pump was numerically simulated. Numerical solutions were obtained for different numbers of blades (z=5, 6, and 7), several particle diameters ranging from 0.02mm to 3mm, and different particle volume fractions (5%, 10%, 20%, and 30%) at the pump inlet. The standard k-ε model and Eulerian multiphase model were applied to study the steady flow. The computational values agreed reasonably well with the modeling experimental results. The results indicated that the particle diameter (ds), particle volume fraction at the pump inlet (IPVF), and blade number significantly influence the pump performance. In general, the relationships between the pump performance parameters (H,η) and IPVF are obviously dependent on the particle diameter. Initially, for the smallest particle diameter (ds), the relationships between pump performance parameters (H,η) and IPVF are linear. As the particle diameter increases, the pump performance parameters (H,η) reduce rapidly with an increase in the IPVF. Furthermore, we found that the performance parameters (H,η) of the pump containing special two-phase flow (ds≤0.1mm) were even higher than those of the pump containing single-phase flow. In addition, the effect of the blade number on the pump performance under the two-phase condition was also investigated. The results showed that the pump with seven blades had a better performance than the other two pumps, except under the condition with large solid particles. These findings can be used to improve the performance of a molten salt pump.

Cuckoo search–based maximum power point tracking controller for PV water pumping system

In this paper, a novel-based tracking controller is developed to ensure maximum power point operation for photovoltaic (PV) water pumping systems (PVWPS). PVWPS consists of a PV array followed by a controlled DC cuk converter which feeds a permanent magnet DC motor coupled with a centrifugal pump. The proposed controller is adaptive-logic based that search, detect and track by using Cuckoo Search (CS) technique. This controller may be specified by three control algorithms, each one has its own constraints for Maximum Power Point tracking achievement. The first two CS control algorithms are based on the sensed old chopping ratio, insolation and temperature as inputs in addition to the PV and motor–pump performance parameters. These controllers are implemented to predict the operating and maximum point voltage and power. The third CS control algorithm is constrained by the outputs of the first two CS control algorithms and motor–pump performance parameters. The third CS controllers are implemented also to predict the optimum DC–DC converter duty ratio based on solar insolation, ambient temperature and motor–pump constants. Each algorithm is provided by its own proposed control function. The new approach has proven accuracy, robustness and effectiveness of efficient energy utilization for stand-alone PVWPS one as it is the most accurate, fastest and easiest.

Investigation of the impact of the geometric dimensions of the impeller on the torque flow pump characteristics

Torque flow pumps (TFP) exhibit low indicators of energy efficiency. This is related to the features in the operating process of their flowing part. Given this, improvement of elements of the flowing part of TFP looks promising in terms of increasing their energy efficiency. Taking into account the structure of the pump life cycle cost, the most rational is the improvement of the impeller design without changing its overall dimensions. This will make it possible to increase the TFP efficiency with minimal investment cost. The study was conducted using the method of experiment planning. This allowed us to rapidly and accurately determine the extent of impact of the selected factors on the pump operating parameters. As a result of numerical investigation, we established the effect of the examined structural elements of the impeller on the pump parameters. A change in the design of the blade enabled a reduction of hydraulic losses in the inter-vane channels of the impeller. Alignment of the blade installation angle with the angle of a fluid inleakage decreased the resistance of input edge of the pump blade. As a result, hydraulic losses at the input of the impeller were reduced. The study conducted allowed us to improve efficiency of the torque flow pump by 4‒5 %. Adequacy of the results of numerical investigation was confirmed by performing a physical experiment.

Numerical Investigation of Short Blades Effect on the Performance of a Centrifugal Pump

Improvement performance of centrifugal pumps is critical to reduce the consumption of electrical energy. One to improve the performance is to break down the circulation near the impeller exit. This can be achieved through the use of shorted blades. Effect of different sizes of shorted blade on pump performance is studied theoretically in this research which, test rig for testing centrifugal pump with standard impeller is constructed. Three impeller configurations with different size shorted blade are installed. The head, flow rate and shaft power are measured at 1500 rotational speed for the standard pump only. Also computational model using “Fluent” under ANSYS is constructed to predict the performance parameters of centrifugal pumps and to analyze the flow field in the impellers’ passages. Standard impeller (A) and three impellers configuration with different shorted blade length of 0.25 (configuration B), 0.2 (configuration C), and 0.15 (configuration D) of the full blade length are analyzed. Computational results show a reduction in flow circulation for all shorted blades impeller comparing to standard impeller. Also static pressure distributions at impeller exit become more uniform for impeller with 0.25, 0.2, and 0.15 shorted blades. The present work proves that the length of short blades have different effects for all pump cases. The best performance in this study occurred when shorted blades have length 25% from the original blade length. So when the effect of shorted blades is needed to study, each case of centrifugal pump should be investigated separately.

Smart de-watering and production system through real-time water level surveillance for Coal-Bed Methane wells

In the past few decades, Coal-Bed Methane (CBM) has become an important source of energy especially in North America. The methane adsorbed within the coal is in a near-liquid state. The open fractures in the cleats are commonly saturated with water. To develop CBM reservoir, water in the fracture and coal seam must be continuously pumped off from coal seam to reduce pressure and desorb gas from matrix.Although operators desire to produce hydrocarbon quickly, a too fast dewatering rate can irreversibly damage matrix desorption process, which can lead to an unfavorable ultimate recovery. Further, the aggressive production rate can potentially release the coal fines and drive them into pump, which increases maintenance effort and cost. Even worse, the de-watering process fluctuates because of the rock porosity and permeability changes resulting from the brittle coal seam and pressure reduction. Therefore, it is critical to adjust the pump operating parameters in a timely manner to maintain a continuous/intermittent production.Ten CBM wells are located in a remote area, which makes the access to wellsites difficult. Previously engineers had to evaluate well performance and optimize the pump on-site, which is limited by a monthly basis. We firstly developed an automatic data processing system using the advanced Echosounders, which can measure the water level in real time. The reservoir pressure can be then monitored dynamically through interpreting the detected water level. With an automatic-wireless data transferring system installed on-site and a closed-loop control program to receive, process, and interpret data, the pump operating parameters can be changed in real time through remote control. This system not only identifies the downhole problems in real time, but also reduces the pump maintenance frequency from 40 days to 75 days statistically and numbers of trip to well site. Further, the gas production rate has been averagely improved by 30% for the 10 wells.The authors firstly developed an automation data processing and control system in the favor of advanced echosounders. Based on the interpreted reservoir pressure, we can avoid aggressive production by adjusting the pump operating parameters in real time, which eventually results in a better ultimate recovery. The developed workflow (automatic echosounder data acquisition, real filed data transferred to central office, data processing, interpretation, and simulation in computational system, adjustment commands to operating system) is especially valuable for the locations difficult to access.

Comparison of energy performance of heat pumps using a photovoltaic–thermal evaporator with circular and triangular tube configurations

In this work, the energy performance parameters of heat pumps using a photovoltaic–thermal evaporator (PV–TE) with circular and triangular tube evaporator configurations are compared. The experimental observations were made in a heat pump under the meteorological conditions of Coimbatore city in India. The standard energy performance parameters of a heat pump (using PV–TE) such as, condenser heating capacity, coefficient of performance (COP), evaporator heat gain, solar energy input ratio and photovoltaic panel efficiency were calculated using experimental observations. The energy performance parameters of the heat pump were simulated using artificial neural networks to have a realistic energy performance comparison. The results show that triangular tube PV–TE configuration has enhanced the major energy performance parameters of the heat pump such as, condenser heating capacity, COP and panel efficiency by 3%–7%, 3%–5% and 4%–13%, respectively when compared to the circular tube PV–TE configuration.

Jet pumps for thermoacoustic applications: Design guidelines based on a numerical parameter study

The oscillatory flow through tapered cylindrical tube sections (jet pumps) is characterized by a numerical parameter study. The shape of a jet pump results in asymmetric hydrodynamic end effects which cause a time-averaged pressure drop to occur under oscillatory flow conditions. Hence, jet pumps are used as streaming suppressors in closed-loop thermoacoustic devices. A two-dimensional axisymmetric computational fluid dynamics model is used to calculate the performance of a large number of conical jet pump geometries in terms of time-averaged pressure drop and acoustic power dissipation. The investigated geometrical parameters include the jet pump length, taper angle, waist diameter, and waist curvature. In correspondence with previous work, four flow regimes are observed which characterize the jet pump performance and dimensionless parameters are introduced to scale the performance of the various jet pump geometries. The simulation results are compared to an existing quasi-steady theory and it is shown that this theory is only applicable in a small operation region. Based on the scaling parameters, an optimum operation region is defined and design guidelines are proposed which can be directly used for future jet pump design.

A New Method to Calculate Centrifugal Pump Performance Parameters for Industrial Oils

Pumping of oil instead of water using centrifugal pumps causes rapid increase in the hydraulic losses which results significant reduction in head and efficiency. Therefore, deriving analytical methods to calculate variation of pump performance parameters versus working fluid viscosity is very important. In the present study, a novel method is proposed to calculate the head (H), efficiency ( ) and input power ( in P ) based on the loss analysis for pumps using industrial oils. A computer code is developed based on represented method and the results of this method are compared with experimental results for a centrifugal pump of type KWP KBloc65-200. The results show good agreement between analytical and experimental methods. Finally, using such computer code, diagrams of head, efficiency and input power versus working fluid viscosity are plotted. The results show an interesting point known as “sudden rising head” which is observed experimentally and numerically in literatures.

First report of 90-day support of 2 calves with a continuous-flow total artificial heart

ObjectiveThe Cleveland Clinic continuous-flow total artificial heart (CFTAH) is a compact, single-piece, valveless, pulsatile pump providing self-regulated hemodynamic output to left/right circulation. We evaluated chronic in vivo pump performance, physiologic and hemodynamic parameters, and biocompatibility of the CFTAH in a well-established calf model. MethodsCFTAH pumps have been implanted in 17 calves total. Hemodynamic parameters, pump performance, and device-related adverse events were evaluated during studies and at necropsy. ResultsIn vivo experiments demonstrated good hemodynamic performance (pump flow, 7.3 ± 0.7 L/min; left atrial pressure, 16 ± 3 mm Hg; right atrial pressure, 17 ± 3 mm Hg; right atrial pressure-left atrial pressure difference, 1 ± 2 mm Hg; mean arterial pressure, 103 ± 7 mm Hg; arterial pulse pressure, 30 ± 11 mm Hg; and pulmonary arterial pressure, 34 ± 5 mm Hg). The CFTAH has operated within design specifications and never failed. With ever-improving pump design, the implants have shown no chronic hemolysis. Three animals with recent CFTAH implantation recovered well, with no postoperative anticoagulation, during planned in vivo durations of 30, 90, and 90 days (last 2 were intended to be 90-day studies). All these longest-surviving cases showed good biocompatibility, with no thromboembolism in organs. ConclusionsThe current CFTAH has demonstrated reliable self-regulation of hemodynamic output and acceptable biocompatibility without anticoagulation throughout 90 days of chronic implantation in calves. Meeting these milestones is in accord with our strategy to achieve transfer of this unique technology to human surgical practice, thus filling the urgent need for cardiac replacement devices as destination therapy.

Design optimization of a synchronal rotary multiphase pump

Design optimization analyses of a synchronal rotary multiphase pump (SRMP) were performed to improve the pump performance. A comprehensive mathematical model of the SRMP was first developed to calculate various pump performance parameters, including the volume flow rate, shaft power consumption, and pump efficiency. The accuracy of the established model was verified by comparisons between the simulated and experimental results. A design optimization procedure coupled with the mathematical model was then developed by employing a direct search optimization technique-complex method. The optimization calculations for the optimum pump performance and the relevant design variables were implemented under three kinds of operating conditions that differed in their inlet gas volume fractions (GVFs). The calculated results showed that the pump efficiency was effectively improved by the set of optimum design variables obtained in the optimization search. The optimum design variables differed with inlet GVF. Under the condition of a lower inlet GVF, the optimum design variables inclined to values that gave a higher mechanical efficiency. When the inlet GVF increased, the effect of leakage loss on the pump efficiency increased, and as a result the optimum design variables inclined to values that gave a higher volumetric efficiency. The research results suggest that a narrow but taller cylinder is better for the operating condition of a lower inlet GVF and a wide but shorter cylinder is better for the operating condition of a higher inlet GVF.

A One-Dimensional Flow Analysis for the Prediction of Centrifugal Pump Performance Characteristics

A one-dimensional flow procedure for analytical study of centrifugal pump performance is done applying the principle theories of turbomachines. Euler equation and energy equation are manipulated to find pump performance parameters at different discharge coefficients. Fluid slippage loss at impeller exit and volute loss are estimated. The fluid slippage is modeled by the slip factor approach using Wiesner empirical expression. The volute loss model counts friction loss associated with the volute throw flow velocity, diffusion friction loss due to circulation associated with volute flow, loss due to vanishing of radial flow at volute outlet, and loss inside pump volute throat. Models for impeller hydraulic friction power loss, disk friction power loss, internal flow leakage power loss, and inlet shock circulation power loss are considered by suitable models. Pump internal volumetric flow leakage and volumetric efficiency are related to pump geometry and flow properties. The procedure adopted in this paper is capable of obtaining performance characteristic curves of centrifugal pump in a dimensionless form. Pump head coefficient, manometric efficiency, power coefficient, and required NPSH are characterized. The predicted coefficients and obtained performance curves are consistent with experimental characteristics of centrifugal pump.