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Auswahl der wissenschaftlichen Literatur zum Thema „Euler's pump equation“
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Zeitschriftenartikel zum Thema "Euler's pump equation"
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Sheth, K. K., G. L. Morrison und W. W. Peng. „Slip Factors of Centrifugal Slurry Pumps“. Journal of Fluids Engineering 109, Nr. 3 (01.09.1987): 313–18. http://dx.doi.org/10.1115/1.3242666.
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Experiments have been carried out in order to determine the effects on slip factor due to the various parameters affecting the performance characteristics of a centrifugal slurry pump. The experiments were conducted with water, sand slurry, and a glass bead slurry at three different pump speeds. Measurements of power, flow rate, head developed by the pump and the density of the slurry were made in order to obtain the characteristic curves of the pump. Using Euler’s equation, equations were derived for calculating the slip and friction factors of the flow. The deduced slip factors for centrifugal slurry pump can be correlated well with suggested non dimensional groups. It shows a consistent trend of decreasing slip factor with increasing slurry mixture density and impeller rotation, or with a decreasing through flow rate. The sizes of the sand and glass bead particles are significantly different (0.71 mm versus 0.09 mm), however, the data correlations do not suggest its effect on the slip factors significantly as the other parameters. The slip factors deduced from head-flow rate curves are more reliable than those deduced from power-flow rate curves, since the shut-off power measurements are likely subjected to errors associated with the particles settling, or the transient effect if the measurements are taken momentarily.
2
Sun, Datong, und Mauricio G. Prado. „Single-Phase Model for Electric Submersible Pump (ESP) Head Performance“. SPE Journal 11, Nr. 01 (01.03.2006): 80–88. http://dx.doi.org/10.2118/80925-pa.
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Summary This paper presents a new incompressible single-phase model for ESP head performance. Sachdeva (1988, 1994) and Cooper and Bosch (1966) developed models for ESP channels and for inducers, respectively. The model presented in this paper is based on 1D approximation along an ESP channel. The new derived pressure ordinary differential equation (ODE) for frictionless incompressible flow (Bird 1960) is consistent with the pump Euler equation. New models for pump frictional and shock losses have been proposed. Finally, a comparison between the predicted pump performance and the pump performances derived from the affinity law for different rotational speeds is presented. The single-phase model can predict ESP performance under different fluid viscosities and also is the basis of a gas/liquid model for ESP head performance. Introduction ESPs are dynamic multistage devices that use kinetic energy to increase liquid pressure. The relationship between the head developed by the pump and the flow rate through the pump for a certain rotational speed is usually known as the pumphead performance curve. This curve is experimentally determined by the pump manufacturer using water as the working fluid. As a consequence, published pumphead performance curves can be used for any other low-viscosity, single-phase liquid, independent of its density. Pump performance, however, is significantly affected by the presence of free gas or high-viscosity fluids. The U. of Tulsa Artificial Lift Projects (TUALP) is currently conducting experimental as well as theoretical research to improve the understanding of pump performance when handling viscous fluids and two-phase flow mixtures at different pump rotational speeds. A better understanding of the pump performance under those conditions will certainly contribute to a reduction in the uncertainty of engineering tools for the selection, design, and operation of ESPs in more challenging applications. This paper presents the new single-phase model developed for the prediction of an ESP's performance. The model consists of the mass and momentum equations, based on the streamline approach or 1D assumption. In the momentum equations, the calculation of the friction factor proposed by Sachdeva is improved by incorporating the channel curvature, channel rotation, and channel cross-sectional effects. A new shock loss model, including rotational speeds, has been proposed. The new single-phase model is capable of predicting the pump performance for different pump rotational speeds and for different fluid viscosities.
3
Yedidiah, S. „An overview of methods for calculating the head of a rotodynamic impeller and their practical significance“. Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 217, Nr. 3 (01.08.2003): 221–32. http://dx.doi.org/10.1243/095440803322328872.
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This paper explains why Euler's equation and the airfoil theory, while analytically correct, sometimes produce disappointing results. It also emphasizes the merits of a recently developed approach and demonstrates its usefulness in solving problems encountered in practice. The subject matter relates, directly, only to rotodynamic pumps. However, with proper modifications, it can be easily expanded to other fluids machines.
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Lee, Y. T., C. Hah und J. Loellbach. „Flow Analyses in a Single-Stage Propulsion Pump“. Journal of Turbomachinery 118, Nr. 2 (01.04.1996): 240–48. http://dx.doi.org/10.1115/1.2836631.
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Steady-state analyses of the incompressible flow past a single-stage stator/rotor propulsion pump are presented and compared to experimental data. The purpose of the current study is to validate a numerical method for the design application of a typical propulsion pump and for the acoustic analysis based on predicted flowfields. A steady multiple-blade-row approach is used to calculate the flowfields of the stator and the rotor. The numerical method is based on a fully conservative control-volume technique. The Reynolds-averaged Navier–Stokes equations are solved along with the standard two-equation k–ε turbulence model. Numerical results for both mean flow and acoustic properties compare well with measurements in the wake of each blade row. The rotor blade has a thick boundary layer in the last quarter of the chord and the flow separates near the trailing edge. These features invalidate many Euler prediction results. Due to the dramatic reduction of the turbulent eddy viscosity in the thick boundary layer, the standard k–ε model cannot predict the correct local flow characteristics near the rotor trailing edge and in its near wake. Thus, a modification of the turbulence length scale in the turbulence model is applied in the thick boundary layer in response to the reduction of the turbulent eddy viscosity.
5
Chami, Francis A. „Use of Simplified Mathematical Formulations in Multi-phase Thermal Pump (MPTP) for Theoretical Prediction of Working Conditions“. Tanzania Journal of Engineering and Technology 30, Nr. 2 (31.12.2007): 130–38. http://dx.doi.org/10.52339/tjet.v30i2.406.
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In this work mathematical expressions have been formed and solved to get predictions of working parameters of multiphase thermal pump (MPTP). MPTP is a simple pump which uses steam to pump water. The results have been comparedwith data found experimentally. Experimental and theoretical values for a range of pressures versus velocity differed byapproximately 8.7% up 12% Through dimensional analysis dimensionless parameters were found Re, Eu, Fo and h/d pmp .These helped to further elucidate the pump’s pumping phenomenon. It was experimentally shown that the Reynoldsnumber found theoretically gave limit of flow operating regime of the pump that it is in the transition regime. Above thisthe pump failed to operate. The Euler dimensionless number gave the dependency of interface velocity on pressurerelation, when pressure was raised the velocity increased. The relation between the two parameters was found to beapproximately quadratic. The Fourier dimensionless number gave the influence of heat transfer properties of thematerial of the pump to the operating characteristics. It was experimentally found that the influence of the overall heattransfer coefficient and heat transfer were the main driving forces behind the operation of the pump. Average interfacevelocities in the pump were found using pipe flow energy and mass conservation equations. Conditions for operation(pumping and suction) of the pump have been established based on the formed mathematical formulations.
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Hatami, Hamed, Ahmad Bagheri und Reza Ansari. „An Analytical Investigation for Vibration Characteristics of a Beam-Type Liquid Micro-Pump“. International Journal of Applied Mechanics 12, Nr. 02 (März 2020): 2050016. http://dx.doi.org/10.1142/s1758825120500167.
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This paper studies the characteristics of a micro-beam interacting with an incompressible fluid in a fluid chamber with an opening in its bottom face for fluid flow. The Euler–Bernoulli equation for transverse deformation of an elastic beam is coupled with the fundamental hydrodynamic equation, which is solved by Galerkin and separation of variables method. The 2D fluid flow assumption in Cartesian coordinate has been used. Natural frequencies and mode shapes of wet beam are calculated and compared with the dry beam. The effects of geometrical parameter changes are also computed as a benchmark for the design of the micro-pump. It is observed that fluid coupling causes a decrease for beam’s natural frequencies, especially in higher modes. Furthermore, since the results of the dry and wet beam show a small discrepancy in lower modes, the mode related to the dry beam was employed as the trial function in the forced vibration analysis of the coupled system.
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Zhang, Heng, und Yan Chao Yin. „Turbulence Numerical Simulation and Particle Track Analysis of Slurry Pump Impeller“. Advanced Materials Research 655-657 (Januar 2013): 336–39. http://dx.doi.org/10.4028/www.scientific.net/amr.655-657.336.
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In order to improve the pump wear performance and optimize pump design, the Euler-Lagrange approach is chosen to simulate the flow in the impeller. The fluid phase is treated as a continuum by solving the N-S equations, while the dispersed phase is solved by using Lagrange Method through the calculated flow field. The results show that the reflex appears in the blade inlet of pressure sides in high flow conditions, but appears in the blade inlet of suction sides in low flow conditions, which possibly induce the cavitation erosion. In low flow conditions, reflex and eddies appear in the blade outlet of both the pressure sides and the suction sides, and the reflex areas even extend to the middle of blades. In the range of simulated conditions, the suction sides don’t collide with particles. The pressure sides collide with particles in the form of continuous impact in low flow conditions but scratch in high flow conditions.
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Mata, V., S. Provenzano, J. L. Cuadrado und F. Valero. „Inverse dynamic problem in robots using Gibbs-Appell equations“. Robotica 20, Nr. 1 (Januar 2002): 59–67. http://dx.doi.org/10.1017/s0263574701003502.
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In this paper, two algorithms for solving the Inverse Dynamic Problem based on the Gibbs-Appell equations are proposed and verified. Both are developed using mainly vectorial variables, and the equations are expressed in a recursive form. The first algorithm has a computational complexity of O(n2) and is the least efficient of the two; the second algorithm has a computational complexity of O(n). This algorithm will be compared with one based on Newton-Euler equations of motion, formulated in a similar way, and using mainly vectors in its recursive formulation. The O(n) proposed algorithm will be used to solve the Inverse Dynamic Problem in a PUMA industrial robot.
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Liu, Ya Jun, Shu Yan Zhan, Jia Kun Ye und Wen Hua Xie. „New Designs in Fuel Dispensing System to Control Maximum Flow of Volatile Liquid“. Applied Mechanics and Materials 868 (Juli 2017): 75–80. http://dx.doi.org/10.4028/www.scientific.net/amm.868.75.
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The dispenser is a fuel pumping and measurement device used in the service station. During the refueling process of volatile liquid, the cavitation phenomenon occur easily due to the large flow rate. The serious cavitation will not only reduce the pumping efficiency, produce loud work noise, but also aggravate the pollution of oil and gas and the energy consumption of the system. Therefore, it is necessary to control the maximum flow rate of the pump. Based on this problem, this paper firstly designs a new flow control valve, and a method of mathematical modeling is proposed to analyze the flow field distribution and the working principle of the whole device based on Euler equation and Bernoulli equation. Then we combine this new hydraulic device to the variable frequency dispenser, a new design of the dispenser structure and a control mode of the maximum flow are proposed. The theoretical research shows that the maximum flow can be limited by optimizing diameter ratio of that flow control valve.
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Valera, A., V. Mata, M. Vallés, F. Valero, N. Rosillo und F. Benimeli. „Solving the inverse dynamic control for low cost real-time industrial robot control applications“. Robotica 21, Nr. 3 (13.05.2003): 261–69. http://dx.doi.org/10.1017/s0263574702004769.
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This work deals with the real-time robot control implementation. In this paper, an algorithm for solving Inverse Dynamic Problem based on the Gibbs-Appell equations is proposed and verified. It is developed using mainly vectorial variables, and the equations are expressed in a recursive form, it has a computational complexity of O(n). This algorithm will be compared with one based on Newton-Euler equations of motion, formulated in a similar way, and using mainly vectors in their recursive formulation. This algorithm was implemented in an industrial PUMA robot. For the robot control a new and open architecture based on PC had been implemented. The architecture used has two main advantages. First it provides a total open control architecture, and second it is not expensive. Because the controller is based on PC, any control technique can be programmed and implemented, and in this way the PUMA can work on high level tasks, such as automatic trajectory generation, task planning, control by artificial vision, etc.
Dissertationen zum Thema "Euler's pump equation"
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Podešva, Adam. „Použití běžného odstředivého čerpadla jako turbíny“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-444636.
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This work deals with the use of a centrifugal pump in turbine mode and control of the system where this machine is operated. The introduction describes and divides the various types of pumps and discusses the issue of Euler's pump and turbine equations. The flow control options are also described here. Part of the work is a research that examines the advantages and disadvantages of using a centrifugal pump in turbine mode, the possibilities of using this system and real applications in the Czech Republic and in the world. The main part is the design of a mathematical model in Microsoft Excel, which solves the regulation of the piping system with a pump operating in turbine mode, especially out of the optimal operating parameters.
Konferenzberichte zum Thema "Euler's pump equation"
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Lee, Yu-Tai, Chunill Hah und James Loellbach. „Flow Analyses in a Single-Stage Propulsion Pump“. In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-139.
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Steady-state analyses of the incompressible flow past a single-stage stator/rotor propulsion pump are presented and compared to experimental data. The purpose of the current study is to validate a numerical method for the design application of a typical propulsion pump and for the acoustic analysis based on predicted flowfields. A steady multiple-blade-row approach is used to calculate the flowfields of the stator and the rotor. The numerical method is based on a fully conservative control-volume technique. The Reynolds-averaged Navier-Stokes equations are solved along with the standard two-equation k-ε turbulence model. Numerical results for both mean flow and acoustic properties compare well with measurements in the wake of each blade row. The rotor blade has a thick boundary layer in the last quarter of the chord and the flow separates near the trailing edge. These features invalidate many Euler prediction results. Due to the dramatic reduction of the turbulent eddy viscosity in the thick boundary layer, the standard k-ε model cannot predict the correct local flow characteristics near the rotor trailing edge and in its near wake. Thus, a modification of the turbulence length scale in the turbulence model is applied in the thick boundary layer in response to the reduction of the turbulent eddy viscosity.
2
Mohammed, Ashfaq C., Shivakumar Ulaganathan, Lingamoorthy Kannan, Anbuchezhian Singaravelu und Girish K. Degaonkar. „Design and Performance Evaluation of an Aero Engine Booster Pump“. In ASME 2015 Gas Turbine India Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gtindia2015-1322.
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The primary function of an aero engine fuel system is to supply metered fuel to the combustion chamber at all operating conditions based on the flow demand set by the engine controller. Centrifugal pump is one of the components in fuel system that feeds fuel to the HP pump. Impeller design is a critical one which dictates the overall performance of centrifugal pump. This paper discusses about design and performance evaluation of impeller with twisted blade configuration. Impeller design is performed based on Euler’s one dimensional theory. Steady state performance of the impeller at design and off-design operating conditions is analyzed by using commercial CFD code ANSYS-CFX with a standard SST turbulence model. The governing mathematical model for flow analysis is a three dimensional incompressible Reynolds Averaged Navier-Stokes (RANS) equation. Cavitation phenomenon is simulated in the CFD multiphase analysis to assess the pump impeller performance under cavitation at different NPSH values. Rayleigh-Plesset cavitation model is used along with RANS equation to perform cavitation analysis. From this study, the simulation method and technique adapted is appropriate for predicting the performance of impeller of centrifugal pump with or without cavitation. Performance of the impeller reduces drastically as there is decrease in NPSH. The prediction of critical NPSH is vital for safer operation of the pump, specifically at high altitude the pump inlet pressure falls which may result in cavitation during operation.
3
Hu, Jing-ning, Jing Wang, Rengui Gu, Ying-ying Tian und Qun Ye. „Numerical Research on Flow Field for Petroleum Tar Cutting Pump“. In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62587.
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In order to study the flow state and distribution of the solid particle in the flow field of petroleum tar cutting pump, the Computational Fluid Dynamic method was used to conduct the numerical simulation of liquid-solid two-phase flow based on Euler-Euler multiphase flow model and standard turbulence equation. The influence of flow rate, revolution speed and tilt angle of stator slot on streamline and distribution of solid concentration were analyzed. The result shows:strong swirl exists in inlet segment in small flow rate, but flow rate has little influence on the solid concentration, so it has no obvious influence on the cutting and grinding efficiency.Grinding efficiency could be improved by increasing revolution speed, but the requirement for the equipment would be higher, so the revolution speed should be determined reasonably. Reducing the tilt angle of stator slot is favor for improving the grinding and cutting efficiency, so it could provide some reference value for the optimal design.
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Schilling, Rudolf, und Moritz Frobenius. „Numerical Simulation of the Two-Phase Flow in Centrifugal Pump Impellers“. In ASME 2002 Joint U.S.-European Fluids Engineering Division Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/fedsm2002-31193.
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The numerical simulations of three types of two-phase flow in centrifugal pump impellers are described. First, the liquid-solid particle flow is modeled by an Euler-Lagrangeian approach assuming a mass concentration less than 5% and particle diameters being less than 1000 microns. The empirical erosion model to predict the local and total wear is calibrated by measurements. Second, the influence of the relative air contents on the head-drop is simulated assuming a relatively small volume fraction and applying a simple one-fluid model. The mixture is characterized by a common density depending on the flow field. Finally, the cavitating flow is studied by implementing the Rayleigh equation into the numerical procedure describing the transient process of bubble growth and collapse. The developed simulation tools are applied to predict the three types of two-phase flows in impellers. Within the defined ranges of application the simulation results agree fairly well with the experimental data.
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Chen, Lingen, Dan Xia, Huijun Feng und Shaojun Xia. „Ecological Optimization for an Endoreversible Chemical Pump With Three Mass Reservoirs“. In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86250.
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This paper firstly educes an energy-based ecological function (EF) which is a compromise between energy pumping rate (EPR) and dissipation of EPR for an endoreversible chemical pump (CP) cycle. By solving the equations of Euler Lagrange, the fundamental optimization relationships of the EF and coefficient of performance (COP) for the CP cycles with linear mass transfer (MT) law and diffusive MT law are derived. The numerical calculations to analyze the influences of the cycle parameters on the relationship between the EF and COP are provided, and the influence of two different MT laws on the EF and COP characteristic is discussed in detail. The maximum EF of the cycle with the linear MT law is bigger than that with the diffusive MT law. The results obtained in this paper can be applied to design a class of devices, such as photochemical, electrochemical and solid-state apparatus as well as mass exchangers, etc.
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Fritsche, Manuel, Philipp Epple, Stefan Gast und Antonio Delgado. „Numerical Investigation of the Euler Turbomachinery Equation and Analysis of the Impact of the Impeller Design on the Fan Performance by an Optimization Study“. In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11572.
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Abstract The working machines such as fans, blowers and pumps are often used for transporting fluids in technical systems. The rotating impeller is used for energy conversion of mechanical work into hydraulic work. Leonhard Euler published this relation of energy conversion in 1752–1756 and is still used today for the basic design of turbomachinery. In the present work, the Euler-Equation is described and presented in detail. Furthermore, a simplified parameterized blade channel of a centrifugal impeller is investigated with numerical simulation methods. The theoretical Euler-Equation is compared and validated with the numerical CFD-results. Based on an extensive CFD-optimization study, the impact of the impeller design parameters on the fan performance has been investigated. For this purpose, the blade shape and the operating conditions (speed and volume flow rate) were systematically varied. After an extensive grid study, the influence of the blade channel contour on the fan performance was investigated. The results of the study are presented in detail.
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Yan, Peng, Peng Wu und Dazhuan Wu. „High Efficiency and Low Pressure Fluctuation Redesign of a Centrifugal Pump Based on Unsteady CFD Analyses“. In ASME/JSME/KSME 2015 Joint Fluids Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/ajkfluids2015-34110.
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In this study, a double volute centrifugal pump of relative low efficiency and high vibration was redesigned with the aid of unsteady CFD analyses. The local Euler head distribution (LEHD) representing the energy growth from the blade leading edge to trailing edge on s1 stream surface in a viscous flow field was introduced to evaluate the flow on s1 stream surfaces from hub to shroud. To investigate the unsteady internal flow of the centrifugal pump, the unsteady Reynolds-averaged Navier-Stokes equations (URANS) were solved with realizable k-ε turbulence model using the CFD code FLUENT. The impeller was redesigned with the same outlet diameter as prototype pump. A two-step-form LEHD was recommended to suppress flow separation and secondary flow encountered in the prototype impeller to improve the efficiency. The splitter was added to improve the hydraulic performance and reduce unsteady radial forces. The original double volute was substituted by a newly designed single volute. The hydraulic efficiency of the redesigned centrifugal pump is 89.2%, 3.2% higher than the prototype pump. The pressure fluctuation in volute is significantly reduced and the mean and max values of unsteady radial force are only 30% and 26.5% of the prototype pump.
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Li, Shiyang, Peng Wu und Dazhuan Wu. „Hydraulic Optimization and Loss Analyses of a Low Specific-Speed Centrifugal Pump With Variable-Thickness Blades“. In ASME 2016 Fluids Engineering Division Summer Meeting collocated with the ASME 2016 Heat Transfer Summer Conference and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/fedsm2016-7814.
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This paper investigates the hydraulic and dynamic performance of a low specific-speed centrifugal pump with CFD simulation. Three different impellers are designed with different thickness distributions along the same mean line of the blades. The entropy production is introduced to study the energy losses in the three models and the energy loss distributions of the whole flow passages are fully revealed. The simplified energy loss equation is carefully validated by comparing the thermodynamic efficiency to the traditional hydraulic efficiency, and the errors between them can be considered acceptable. The circumferential Euler head distribution out of the impeller is used to predict the uniformity of the flow into the volute. To obtain the transient flow characteristics, the sliding mesh technique and the unsteady CFD simulation are applied and the pressure pulsations in the volute are well captured. The head fluctuation intensities of the three models are quantitatively compared under constant flow rate. The results show that the thickness distribution can affect the hydraulic performance to a large extent, and it can strongly affect the pressure pulsation in the volute.
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Kruisbrink, A. Ch H., und S. J. Pickering. „Analytical Modelling of a Fluid Coupling“. In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59528.
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In this paper an analytical model is presented for fluid couplings in aero-engine applications. It can be used to predict the performance of fully filled as well as partially filled couplings in terms of a transmitted torque. As such it will lead to a predictive tool for design purposes. The model makes use of toroidal coordinates. This allows for the assessment of the mass flux and angular momentum flux within the entire toroid halves, formed by the driving unit (pump) and driven unit (turbine). In previous work only the fluxes at the coupling plane (between pump and turbine) could be evaluated, since cylindrical coordinates were used. The Euler equations in toroidal coordinates are used to obtain approximate solutions for the 2D pressure field within these toroid halves. Assuming that the pressure within an air cavity of a partially filled coupling is constant, the air-oil interface, flow regime (annular, stratified) and fill status are obtained from contours of constant pressure. In previous work the pressure distribution is not considered, except in criteria for the flow regimes, based on the centrifugal and vortex head in the coupling plane. The analytical model is validated. It shows a good agreement with torque measurements on a fully filled coupling, after a Reynolds dependency for the power loss coefficients is introduced. It shows a reasonable, qualitative agreement with CFD simulations on a partially filled coupling, after the solution for the pressure distribution is corrected for the variable vortex speed and radial velocity component. The analytical approach is efficient compared to CFD, which is very expensive in terms of CPU times, in particular for the two-phase flow in partially filled fluid couplings.
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Engeda, Abraham. „Early Historical Development of the Centrifugal Impeller“. In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-022.
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The centrifugal impeller has been in existence for over two hundred years but its perfection and rapid development occurred only in the last sixty years. This paper deals with the early development of the centrifugal impeller in the last and early this century. The centrifugal impeller is found in centrifugal pumps and compressors. Next to the electric motor, centrifugal pumps and compressors are believed to be the most widely used machines of our time. The field of application of these rotary machines has been continually widening, as they are developed for handling a wider range of liquids and gases at higher pressure and greater temperatures, and whole industries become more and more dependent on them. The first centrifugal impeller with ten wooden double curved blades and dating back to the fifth century was found in 1772 in an abandoned Portuguese copper mine in San Dominigos. Centrifugal fans had been used for mine ventilation as early as in the sixteenth century. The invention of the centrifugal impeller is a disputed issue whether the credit goes to Leonardo Da Vinci (1452–1519), who suggested the idea of using centrifugal force for lifting liquid, or to Johann Jordan about 1680. Most place the origin of the centrifugal impeller with Denis Papin in 1689. The importance of Papin’s contribution lies in his understanding of the concept of creating a forced vortex within a circular, or spiral casing by means of blades. Following Papin, Kernelien Le Demour in 1732 and Daniel Gabriel Fahrenheit in 1736 described other designs for centrifugal impellers, but there is no evidence of their practical use. Euler presented in his 1754 memoir an idealized theoretical application of Newton’s law to centrifugal impellers, based on a conceptualization of his tubular turbine run backwards and now universally known as the “Euler equation”. His publication caused a great development of hydraulic turbines in the eighteenth century, but did little to influence the development of centrifugal impellers, which had to gradually develop through tedious cut-and-try methods. The one thing Euler contributed was to initiate a true mathematical inquiry into the employment of centrifugal force as a means of raising fluid. About the same time as Euler, John Smeaton introduced in 1752 the study of turbomachinery by models. He also defined power as equivalent to the rate of lifting of a weight, a concept that is still fundamental in thermo-fluids. Today both centrifugal pumps and compressors have reached efficiency levels above 90% and are built in sizes from a few Watts to Megawatts. This paper traces the early historical development of the centrifugal impeller. Factors that promoted and hindered the early development are also discussed.