centrifugal pump and positive displacement pump|peristaltic pump vs positive displacement

A pump is a device that raises or transfers fluid. Pumps come in many forms, but can generally be categorised according to two main operating principles: Positive displacement pumps and centrifugal pumps. This article deals exclusively with centrifugal pumps. Centrifugal pumps serve many purposes:

On August 19, 2024, understanding pump curves, such as the positive displacement pump curve vs centrifugal pump curve, and matching the pump’s performance to the specific needs of a system is crucial for efficient operation. In this article, we will delve into the differences between positive displacement pumps and centrifugal pumps, exploring their advantages, disadvantages, and applications in various industries.

The Main difference between Centrifugal pump & Positive displacement pump are as follows. Principle of operation: Centrifugal pumps use centrifugal force to move fluid, while positive displacement pumps use a mechanical means, such as a

Positive Displacement Pump

Positive displacement pumps are a type of pump that moves fluid by trapping a fixed amount of it and then forcing it into a discharge pipe. These pumps are known for their ability to deliver a constant flow rate regardless of the discharge pressure. There are several types of positive displacement pumps, including rotary, reciprocating, and diaphragm pumps.

Positive Displacement Pump Disadvantages

While positive displacement pumps offer many benefits, they also have some disadvantages. One of the main drawbacks of positive displacement pumps is their limited efficiency at high flow rates. These pumps can struggle to maintain a consistent flow when operating at high speeds, leading to potential issues with cavitation and overheating.

Positive Displacement Pump vs Diaphragm Pump

Diaphragm pumps are a type of positive displacement pump that uses a flexible diaphragm to move fluid. Unlike other types of positive displacement pumps, diaphragm pumps offer pulsation-free operation, making them ideal for applications where a smooth flow is essential. However, diaphragm pumps are typically more expensive and require more maintenance than other types of positive displacement pumps.

Positive Displacement Pump vs Non-Positive Displacement Pump

Non-positive displacement pumps, such as centrifugal pumps, operate by imparting kinetic energy to the fluid to increase its velocity. Unlike positive displacement pumps, non-positive displacement pumps do not trap and displace a fixed volume of fluid with each revolution. Instead, they rely on centrifugal force to move the fluid through the pump.

Peristaltic Pump vs Positive Displacement Pump

Peristaltic pumps are a type of positive displacement pump that uses rotating rollers to compress a flexible tube and move fluid through the pump. These pumps are known for their gentle pumping action, making them ideal for handling shear-sensitive fluids. However, peristaltic pumps can be prone to wear and require regular maintenance to prevent leaks and failures.

Below is a quick comparison table that highlights the main performance differences between centrifugal (rotodynamic) pumps and positive displacement pumps. Impellers pass on velocity from the motor to the liquid …

For a pump impeller with hub and tip diameters and respectively and rotating with an angular speed , we have and . And from the outlet velocity triangle, . Bottom-line: The vanes of centrifugal pumps are curved backward to prevent overloading of the impeller motor. .

centrifugal pump and positive displacement pump|peristaltic pump vs positive displacement