Mixed-Flow Pumps : Modeling, Simulation, and Measurements / Wei Li [and four others].

Format:

Book

Author/Creator:

Li, Wei (Professor of engineering), author.

Contributor:

Ji, Leilei

Agarwal, Ramesh

Shi, Weidong

Zhou, Ling

Series:

Wiley-ASME Press series.

Wiley-ASME Press Series

Language:

English

Subjects (All):

Centrifugal pumps.

Computational fluid dynamics.

Physical Description:

1 online resource (333 pages)

Edition:

First edition.

Place of Publication:

Hoboken, NJ : John Wiley & Sons Inc., [2024]

Summary:

Mixed-flow Pumps Modeling, Simulation, and Measurements Learn to improve and optimize the design and operation of mixed-flow pumps Mixed-flow pumps have a huge range of applications in agriculture, hydroelectric power, and other industries that incorporate fluid transport. They are centrifugal pumps incorporating the characteristics of both axial and radial pumps to increase the flow rate and discharge pressure. Though essential in a variety of industries, they pose serious challenges to numerical simulation methods, challenges which are starting to be met by the application of computational fluid dynamics using high-performance computing. Mixed-flow Pumps introduces engineers and researchers to this subject and its important applications. Incorporating all major varieties of mixed-flow pumps used in industrial applications, it employs methods from advanced computational fluid dynamics and high-precision flow field experimentation to characterize and analyze these crucial technologies. Moving from the fundamentals of the technology to its most advanced applications, it's an essential resource for engineers and industry practitioners looking to develop their understanding of fluid transport. Mixed-flow Pumps readers will also find: * Detailed information on how to design and optimize mixed-flow pumps to meet the increasingly stringent industry demands * Detailed information on energy performance tests and experiments, methods for data analysis, entropy production theory, CFD solutions using Reynolds-Averaged Navier-Stokes (RANS) equations, and more * An authoritative team with immense global experience in flow pumps and broader industrial experience Mixed-flow Pumps is a useful reference for mixed-flow pump design by academic researchers, including graduate students, industry practitioners, and test engineers.

Contents:

Cover

Title Page

Copyright

Contents

Preface

Acknowledgments

List of Acronyms

List of Symbols

Chapter 1 Introduction

1.1 What Is a Mixed‐flow Pump?

1.2 Types of Mixed‐flow Pumps

1.3 Agricultural and Industrial Applications of Pumps

1.4 Summary

References

Chapter 2 Basic Concepts and Theory of Mixed‐flow Pumps

2.1 Basic Flow and Performance Parameters

2.1.1 Volume Flow Q

2.1.2 Head H

2.1.3 Speed n

2.1.4 NPSH

2.1.5 Power and Efficiency

2.2 Typical Type of Flows in the Mixed‐flow Pumps

2.2.1 Tip Leakage Flow

2.2.2 Rotating Stall

2.2.3 Cavitation Flow

2.3 Summary

Nomenclature

Chapter 3 Brief Review of Computational Fluid Dynamics

3.1 CFD as a Flow Simulation Tool

3.2 Geometry Modeling

3.3 Mesh Generation

3.4 Governing Equations of Fluid Dynamics

3.5 Simulation of Turbulent Flows

3.6 Turbulence Modeling

3.6.1 Standard k− Model

3.6.2 Shear Stress Transport (SST) k−ω Model

3.6.3 Spalart-Allmaras (SA) Model

3.6.4 Wray-Agarwal (WA) Model

3.6.5 Detached Eddy Simulation Model

3.6.6 Large Eddy Simulation (LES) Model

3.7 Numerical Solution Algorithms

3.7.1 Numerical Discretization Method

3.7.2 Flow Field Solution Method

3.8 Near‐wall Flow Treatment

3.9 Boundary Conditions

3.10 Uncertainty Analysis

3.11 Summary

Chapter 4 Pump Performance Analysis Methods

4.1 Entropy Production Analysis

4.2 Vortex Identification and Vorticity Transport

4.2.1 Vortex Identification

4.2.1.1 Q‐Criterion

4.2.1.2 Regularized Helicity Method

4.2.2 Vorticity Transport

4.3 Transient Flow Analysis Using the Wavelet Method

4.4 Summary

Chapter 5 Experimental Methods, Data, and Analysis

5.1 External Characteristics Experiment

5.1.1 Test Equipment and Instruments.

5.1.2 Test Method for External Flow Characteristics of the Pump

5.1.3 Uncertainty Analysis of the Experiment

5.1.4 Test Results for External Flow Characteristics of the Pump

5.2 Experiment for Measuring Pressure Fluctuations

5.2.1 Experimental Procedure

5.2.2 Wavelet Transform of Pressure Pulsation for Different Tip Clearances

5.2.3 Coherence of Pressure Pulsation for Different Tip Clearances

5.3 PIV Measurement

5.3.1 Basic Principles of PIV Measurement

5.3.2 The PIV Image Processing System

5.3.3 PIV Measurement Criteria

5.3.4 PIV Testing Instruments and System

5.3.5 PIV Test Method

5.3.5.1 Selection and Addition of Tracer Particles

5.3.5.2 Calibration Apparatus

5.3.5.3 Lens Group, Camera Fixing, and Adjustment

5.3.5.4 Shooting Section of the Dynamic and Static Interference Flow Field

5.3.5.5 Positions of the Equipment and the Shooting Sections

5.3.6 Analysis of the PIV Results for the Flow Field of the Front Shaft Section of the Impeller Inlet

5.3.7 Relative Velocity Distribution at the Monitoring Lines in Different Phases at the Impeller Inlet and Outlet Under the Part‐loading Conditions

5.4 Orbit of Shaft Centerline

5.4.1 Measurement of the Spindle Axis Trajectory

5.4.2 Characteristics of Vibrations of the Shaft System

5.4.3 Original Axis Trajectory Diagram and Time‐domain Diagram

5.4.4 Decomposition and Refinement of the Rotor Axis‐centered Trajectory

5.4.5 Flow Spectrum Analysis

5.4.6 Effect of the Rotor-Stator Interaction on the Shaft Vibration

5.5 Summary

Chapter 6 CFD Simulations of a Mixed‐flow Pump Using Various Turbulence Models

6.1 Comparison and Validation of Numerical Results from Three Two‐equation Turbulence Models (SST k-ω, k-ω, and Standard k- )

6.1.1 Comparison of Energy Performance.

6.1.2 Comparison of CFD Results with Phase‐Averaged Velocity Predictions from PIV

6.1.3 Flow Field Under Incipient Stall Condition

6.2 Application of Wray-Agarwal (WA) One‐Equation Turbulence Model

6.2.1 Energy Performance Comparison

6.2.2 Comparison of the Flow Field in the Rotor-Stator Interaction Zone Using Different Turbulence Models

6.2.3 Comparison of Eddy Viscosity Variable R &amp

equals

k/ω in the Pump Using the Four Turbulence Models (SST k-ω, k-ω, k- , and WA)

6.3 Summary

Chapter 7 Tip Leakage Flow In a Mixed‐flow Pump

7.1 Energy Characteristics

7.1.1 Comparison of Energy Performance of the Pump for Various Tip Clearances

7.1.2 Distribution of the Total Entropy Production in the Pump for Various Tip Clearances

7.1.3 Local Entropy Production Rate in the Impeller

7.1.4 Local Entropy Production Rate in the Guide Vane

7.2 Flow Structures

7.2.1 Vortex Patterns in the Blade Rim Region of the Pump for Various Tip Clearances

7.2.2 Tip Leakage Vortex (TLV) Intensity and the Vortex Core Distribution

7.3 Unsteady Flow Characteristics

7.3.1 Time‐domain Analysis of the Pressure Pulsations

7.3.2 Frequency‐domain Analysis of the Pressure Pulsation

7.4 Transient Flow Field Due to Rotor-Stator Interaction (RSI)

7.4.1 Flow Fields Before the RSI Zone

7.4.2 Flow Fields in the RSI Zone

7.4.3 Pressure Fluctuation in Partial‐loading Conditions

7.4.3.1 Time‐domain Analysis

7.4.3.2 Frequency‐domain Analysis

7.5 Summary

Chapter 8 Rotational Stall in a Mixed‐flow Pump

8.1 Energy Characteristics

8.1.1 Energy Performance of the Pump Along the Axial Flow Direction

8.1.2 Energy Loss Mechanism Under Stall Condition

8.1.2.1 Theoretical Analysis of Head Drop in Saddle Area

8.1.2.2 Flow Distribution in Each Channel.

8.1.2.3 Region of the Maximum Energy Loss in the Impeller

8.2 Flow Structure in the Critical and Deep Stall Conditions

8.2.1 Flow Structure in the Impeller in the Design, Critical, and Deep Stall Conditions

8.2.2 Key Factors Causing the Energy Loss

8.2.2.1 Influence of the Inlet Swirl on Energy Loss

8.2.2.2 Influence of the Tip Leakage Vortex on the Energy Loss

8.2.2.3 Influence of the Stall Vortex on the Energy Loss

8.2.2.4 Influence of the Backflow Vortex on the Energy Loss

8.3 Effect of the Tip Clearance on the Rotating Stall

8.3.1 TLF Patterns and TLV Core Trajectories for Different Tip Clearances

8.3.2 Influence of the Inlet Swirl Flow and the TLV Characteristics

8.3.3 Distorted Flow in the Blade Rim Region Below the TLV

8.4 Propagation Characteristics of Rotating Stall

8.4.1 Pressure Fluctuation Characteristics of the Flow in the Stall Condition

8.4.2 Correlation Between the Transient Flow Field and the Energy Characteristics of the Pump

8.4.3 Morphology and Propagation Mechanism of Rotating Stall

8.5 Inducements for the Circumferential Propagation of the Rotating Stall

8.6 A Stall Prediction Model of the Mixed‐flow Pump

8.6.1 Flow Characteristics During the Process of the Stall for Impellers with Different Blade Numbers

8.6.2 Quantitative Analysis of the Suction Surface Parameters of the Stalled Blades

8.6.3 The Pressure and Velocity Distributions on the Suction Side of the Blade of the Impellers with Various Blade Numbers

8.6.4 A Simple Stall Prediction Model

8.7 Summary

Chapter 9 Passive Suppression of Rotating Stall in Mixed‐flow Pump

9.1 Introduction

9.2 Impeller Blade Rim Structures for Stall Suppression

9.2.1 Geometries of Various Blade Rim Structures

9.2.2 Results of Numerical Calculations for Various Blade Rim Structures.

9.2.2.1 Comparison of the External Characteristics of the Pump for Various Blade Rim Structures

9.2.2.2 Influence of Blade Rim Geometry on the Flow Field in Rim Clearance Region

9.2.2.3 Influence of Blade Rim Structure on the Inlet Flow Angle of the Impeller

9.2.2.4 Distribution of Vortex Structures in the Impeller with Different Rim Structures

9.3 Influence of the Circumferential Spokes

9.3.1 The Structure of "O‐Spoke"

9.3.2 Analysis of Results

9.3.2.1 External Characteristics Analysis

9.3.2.2 Analysis of the Flow Field in Various Cross‐Sectional Areas of the Pump

9.3.2.3 Flow Field Analysis in the Impeller Shroud Region

9.3.2.4 Energy Performance Analysis Based on the Entropy Generation Theory

9.3.2.5 Analysis of the Blade Height Section Flow Field

9.4 Summary

Chapter 10 Cavitation in a Mixed‐flow Pump

10.1 Numerical Model

10.1.1 Cavitation Model

10.1.2 Numerical Simulation Setup and Boundary Conditions

10.1.3 Cavitation Test Procedure

10.1.4 Comparison of Numerical Simulations and Cavitation Test Results

10.2 Flow Characteristics of the Mixed‐flow Pump Under Cavitation

10.2.1 Blade Surface Load Distribution

10.2.2 Trajectory of TLV for Different Values of NPSHa

10.2.3 Evolution of the Transient Flow Trajectory of the TLV and Tip Cavitation Flow

10.3 Analysis of Cavitation Energy Characteristics

10.3.1 Analysis of Pump Energy Characteristics

10.3.2 Analysis of Energy Loss in the End Wall Region of the Pump Caused by the TLV‐Induced Cavitation

10.3.3 Effect of Cavitation on the Output Power of the Pump

10.3.4 Effect of Cavitation on Energy Losses in the Pump

10.4 Summary

Chapter 11 Analysis of the Vortex Dynamics Characteristics in the Tip Region of the Mixed‐flow Pump Under Cavitation.

11.1 The Tip Leakage Flow Characteristics Under Cavitation.

Notes:

Includes bibliographical references and index.

Publisher supplied metadata and other sources.

Description based on print version record.

ISBN:

9781119910374

1119910374

9781119910381

1119910382

9781119910794

111991079X

OCLC:

1427350221