fluid mechanics centrifugal pump|schematic diagram of a pump

The dead head of a pump is a condition in which a centrifugal pump operates continually without any fluid flow through the pump. This leads to undesirable consequences for the pump .

Different types of centrifugal pumps are widely used in various industries worldwide. These pumps are classified based on the number of impellers, type of casing, orientation, and position. Understanding the working principles and design of centrifugal pumps is essential for efficient fluid handling processes.

It is one of the simple and exciting topics in fluid mechanics.What is the need for a pump? We require a pump to transmit water from a region of low pressure to a region of higher pressure. The centrifugal pump defines as a hydraulic machine that converts mechanical energy into hydraulic energyby means of a

Based on the Number of Impellers

# Single Stage Impeller

A single stage centrifugal pump consists of only one impeller that rotates within a casing to create fluid flow. The impeller is designed with curved vanes that accelerate the fluid radially outward. As the fluid moves through the impeller, it gains kinetic energy, which is then converted into pressure energy as it exits the pump. Single stage centrifugal pumps are commonly used for low to medium flow rate applications where moderate pressure is required.

# Multi-Stage Impeller

Multi-stage centrifugal pumps have multiple impellers stacked in series within the same casing. Each impeller adds energy to the fluid, resulting in higher pressure outputs compared to single stage pumps. These pumps are suitable for high-pressure applications such as boiler feed water systems, reverse osmosis, and high-pressure cleaning systems.

Type of Casing

Centrifugal pumps can also be classified based on the type of casing design:

# Volute Casing

A volute casing is a spiral-shaped casing that gradually expands in diameter from the inlet to the outlet. This design helps in converting the kinetic energy of the fluid into pressure energy efficiently. Volute casings are commonly used in single stage centrifugal pumps for handling liquids with low viscosity.

# Diffuser Casing

In a diffuser casing, the fluid is directed through a series of stationary vanes called diffuser vanes after leaving the impeller. These vanes help in converting kinetic energy into pressure energy more effectively, making diffuser casings suitable for multi-stage centrifugal pumps.

Orientation and Position

# Horizontal Centrifugal Pump

Horizontal centrifugal pumps have a horizontally oriented shaft and are widely used in industrial applications for transferring liquids from one point to another. These pumps are easy to install and maintain, making them popular in various industries.

# Vertical Centrifugal Pump

Vertical centrifugal pumps have a vertically oriented shaft and are commonly used in applications where space is limited. These pumps are designed to operate efficiently in submerged conditions and are often used in sump pump applications.

How Centrifugal Pumps Work

Centrifugal pumps work on the principle of centrifugal force, where the rotating impeller accelerates the fluid radially outward. This acceleration creates a low-pressure zone at the center of the impeller, causing the fluid to be drawn into the pump. The fluid then exits the pump at a higher pressure due to the conversion of kinetic energy into pressure energy.

Schematic Diagram of a Centrifugal Pump

A typical centrifugal pump consists of an impeller, casing, inlet, outlet, and shaft. The impeller is connected to the shaft, which is driven by a motor. As the impeller rotates, it imparts energy to the fluid, which is then discharged through the outlet of the pump.

Single Inlet Centrifugal Pump Disadvantages

One of the disadvantages of single inlet centrifugal pumps is their limited efficiency at low flow rates. These pumps may experience recirculation and cavitation issues when operating below their design flow range. Additionally, single inlet pumps may have higher axial thrust loads compared to double suction pumps.

Centrifugal Pump Velocity Diagram

The velocity diagram of a centrifugal pump illustrates the flow path of the fluid as it passes through the impeller. The fluid enters the impeller at a low velocity and is accelerated to a higher velocity as it moves radially outward. The velocity diagram helps in analyzing the performance of the pump and optimizing its design for maximum efficiency.

Explain Working of Centrifugal Pump

The different parts of the centrifugal pumpare listed below. 1. Shaft and shaft sleeve 2. Impeller 3. Casing 4. Suction Pipe 5. Delivery Pipe See more

How does a multistage centrifugal pump work? A multistage pump operates by utilizing multiple impellers arranged in series within the pump casing. Each impeller is responsible for increasing the pressure of the fluid as it passes through. As the fluid enters the pump, it is drawn into the first impeller, where it gains some pressure.A self-priming pump is a centrifugal pump that has the ability to draw liquid from a level underneath its suction port without an exterior priming aid. The name of a self-priming pump represents that it has the capability to prime itself. For this reason, the accessory priming chamber or the housing must have adequate . See more

fluid mechanics centrifugal pump|schematic diagram of a pump