Design And Construction Of Centrifugal Pump Impeller

ABSTRACT

Centrifugal pumps are used widely in different industries for various industrial purposes. Since performance of pump is affected by vibrations and depends on the blade inlet or outlet angle. The performance of the centrifugal pumps can be improved by alternating the geometric characteristics of impeller in the pumps. Centrifugal pump performance mainly depends upon blade exit angle. The rotating of the blade is based on the natural frequency and mode shapes. The impeller chosen for the study was a single- entry impeller with radial vanes. Using Creo 4.0 and ANSYS Workbench software the modeling and simulation of the impeller have been carried out. The respective frequencies and corresponding mode shapes impeller were measured by using eigenvalues and eigenvectors respectively. The results showed that the varying impeller blade exit angle had significant effect on natural frequency of the impeller.

Keywords: ANSYS, centrifugal pump, natural frequency, outlet blade angle, pump impeller

COVER PAGE

CERTIFICATION

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

CHAPTER ONE

INTRODUCTION

• BACKGROUND OF THE STUDY
• PROBLEM STATEMENT
• AIM AND OBJECTIVES OF STUDY
• SIGNIFICANCE OF STUDY
• SCOPE OF STUDY

CHAPTER TWO

LITERATURE REVIEW

2.1    CENTRIFUGAL PUMP

2.2    CENTRIFUGAL PUMPS PRINCIPLE OF OPERATION

2.3    DIFFERENT TYPES OF CENTIFRUGAL PUMP

2.4    IMPELLER – TYPES OF IMPELLERS

2.5      REVIEW OF RELATED STUDIES

CHAPTER THREE

DESIGN METHODOLOGY

3.1    METHODOLOGY

3.2    PUMP SPECIFICATIONS

3.3    VANE PROFILE DEVELOPMENT

3.4      MODELING OF IMPELLER

3.5      MODAL ANALYSIS BY VARYING ANGLE

3.6      MATERIAL SELECTION

CHAPTER FOUR

RESULTS/ANALYSIS

4.1 RESULTS AND DISCUSSION

CHAPTER FIVE

CONCLUSION

REFERENCES

CHAPTER ONE

1.0                                         INTRODUCTION

1.1                           BACKGROUND OF THE STUDY

Pumps are machines that convert the mechanical energy they receive from the power source into hydraulic energy. By creating low pressure in the suction line, it enables the fluid to reach the pump impeller and transmits the fluid to the desired point by pressing the outlet pipe. Pumps are generally divided into positive (volumetric-volumetric-displacement) pumps and non-positive (centrifugal, dynamic) pumps according to their manufacturing methods and operating principles.

The volumetric displacement pumps transmits the fluid through discrete. The fluid is pushed periodically. Their efficiencies are high. Dynamic or centrifugal pumps provide continuous energy to the fluid. Fluid movement is not discrete. It is continuous. That is, while the fluid is absorbed on one side, it is pumped on the other hand. Centrifugal pumps take up less space, are light and cheap. Speeds are higher. Their efficiencies are low. Flow rate adjustment is easier. Centrifugal pumps are the most commonly used type of pumps in agricultural irrigation [1].

Centrifugal pump parts are examined in two sections as fixed and moving parts. Moving parts consist of pump shafts, impeller, sealing rings connected to impeller. The fixed parts consist of suction and discharge nozzles, housing, bearings, coupling, sealing elements, stuffing box and roof (chassis) (Figure 2). The centrifugal impeller is the active part of the pump and is the moving part of the pump with the shaft. The impeller transforms the mechanical energy that receives from the engine into the hydraulic energy and has a different number of curved blades on it. The body collects the liquid from the impeller and transmits it to the discharge pipe.

1.2                                   PROBLEM STATEMENT

Numerous challenges are faced during the fabrication of a pump impeller such as low Pump Pressure, leaks and abnormal sounds which are linked to poor construction of the impeller. This study was carried out to provide a means of constructing a centrifugal pump impeller accurately.

1.3                        AIM AND OBJECTIVES OF THE STUDY

The main aim of this work is to construct a centrifugal pump impeller using locally available material. The objectives of the work are;

1. To fabricate the impeller at low cost.
2. To design a single- entry impeller with radial vanes

• To carry out the simulation of the impeller using Creo 4.0 and ANSYS Workbench software

1.4                                 SCOPE OF THE STUDY

The scope of this work covers the building of a centrifugal pump impeller. The centrifugal pump performance mainly depends on the impellers. Impeller blade exit angle has a significant effect on the vibration during the working conditions. In centrifugal pump the rotating component is an impeller, it drives the pump with help of motor accelerated the fluid being pumped outwards from the center of rotation. Modeling of impeller is done by using creo 4.0 and model analysis is carried out changing the different blade angles corresponding natural frequency, stress and strain values are taken [2-3].

1.5                            SIGNIFICANCE OF THE STUDY

This study will serve as a means of constructing the impeller with accurate blade placement.

The study will also serve as a means of enlightening the reader on how a centrifugal pump works and the construction details.