Positive displacement pumps are used for foam, and dynamic pumps are used for water delivery.
A centrifugal pump is a type of dynamic pump that uses a revolving impeller, also known as vanes, that is submerged in the fluid being pumped and has a housing to guide the flow of water.
Positive displacement pumps hold separate fluid sections that are contained before being carried along; dynamic pumps maintain a constant fluid flow.
Well, in this reading, we’ll explore what a dynamic pump is, its applications, parts, diagram, and how it works. We’ll also explore its advantages and disadvantages.
Let’s begin!
What is Dynamic Pump?
The dynamic pump is a type of velocity pump that increases the fluid’s flow velocity to add kinetic energy. When the velocity is decreased before or as the flow leaves the pump and enters the discharge pipe, this energy increase is transformed into a gain in potential energy (pressure).
The First Law of Thermodynamics, or more precisely Bernoulli’s principle, explains this transformation of kinetic energy into pressure. Positive displacement pumps are used for foam while dynamic pumps are used for water delivery.
Depending on how the velocity gain is attained, dynamic pumps can be further classified. These kinds of pumps have several traits, including:
Constant energy is the transformation of more energy into kinetic energy (increase in velocity).
Greater pressure head as a result of greater velocity (kinetic energy) The way dynamic and positive-displacement pumps function in closed valve situations is one of their practical differences.
Because positive-displacement pumps physically move fluid, shutting a valve downstream of one might result in a persistent pressure buildup that may eventually cause the pipeline or pump to mechanically collapse.
One difference with dynamic pumps is that they may be used safely with closed valves (for brief periods of time).
Applications
The application of a dynamic pump is purposely for water supply. They can also be used for pumping crude oil, which is why they are widely used in the petroleum industries.
Dynamic pumps can also be used for commercial and household applications. Chemical industries also make good use of this pump.
These pumps are also used in the food industry for passing water across the factory. Also, they are used in the fire protection industries to pass pressurised water.
Stormwater, subsurface water, sewage, rainfall, black and grey water, trade waste, chemicals, bore water, and food items may all be moved with these pumps.
Finally, dynamic pumps are used for cellulose, petrochemicals, hydrocarbons, paint, and beverage production.
Related: What is Hydraulic Pump? its Diagram and How it Works
Parts and Diagram
Types of Dynamic Pump
The various types of dynamic pumps include:
- Centrifugal Pumps
- Vertical Centrifugal Pumps
- Horizontal Centrifugal Pumps
- Submersible Pumps
- Fire Hydrant Systems
Centrifugal Pumps
Centrifugal pumps are the most used pump types in the world. They work perfectly well in simple principle. This pump is robust, effective, and inexpensive to produce. The fluid pressure will rise from the pump’s input to its exit whenever it is operating.
The liquid will be forced throughout the system by the pressure change.
Vertical Centrifugal Pumps
Vertical types of centrifugal pumps are also called cantilever pumps. Because the bearings are outside the pit, these pumps have a unique shaft and a design that allows the volume to fall into the pit.
This pump type employs a throttle bushing in place of a filling container to cover the shaft. This type of pump is commonly used as a parts washer.
Horizontal Centrifugal Pumps
These pumps have at least two or more impellers, which is why they are perfectly used in pumping services, as each step is a divided pump.
Every phase is situated on the same shaft and in a similar shelter. At least eight stages can be installed on a single horizontal shaft; additional stages may be added. The head improves by about the same amount at each level.
Submersible Pumps
Submersible types of pumps are also called septic, sewage, and stormwater pumps. They are often used in building services, residential, commercial, industrial, rural, municipal, and rainwater recycling.
Various impellers, such as closed, contra-block, vortex, multi-stage, single-channel, cutter, and other grinder pumps, are the primary uses for these pipes.
A wide range of options, including high flow, low flow, low head, and otherwise high head, are available for various purposes.
Fire Hydrant Systems
Fire hydrant pump systems, also known as hydrant boosters, fire pumps, and firewater pumps, are high-force water pumps designed to increase the capacity of construction firefighting by increasing the force within the hydrant service because mains are insufficient.
The system’s primary applications are water transfer and irrigation.
Working Principle of Dynamic Pump
The working of a dynamic pump can be determined by the specific type, as there are various kinds today. However, we’ll be explaining the centrifugal type since they are the most common.
In the working principle of a centrifugal dynamic pump, the fluid pressure will rise from the pump’s input to its exit whenever it is operating. The liquid will be forced throughout the system by the pressure change.
By transferring mechanical power from the electrical motor to the liquid via the rotating impeller, this type of pump increases internal force. The liquid flow will enter the impeller’s centre and escape with the blades.
The fluid’s velocity is therefore increased by centrifugal power, which also converts kinetic energy into force.
Advantages and Disadvantages of Dynamic Pump
Dynamic pumps, with their small sizes and ease of maintenance, offer advantages such as control of low- to medium-viscosity fluids and low head to medium head.
However, they also face problems such as shaft misalignment, impeller damage, wear ring damage, seal ring damage, and rapid bearing damage due to overshooting.
Despite these challenges, dynamic pumps remain cost-effective and effective in their applications.
FAQs
What is the difference between a kinetic pump and a dynamic pump?
Kinetic pumps, also known as fluid-dynamic pumps or turbopumps, are machines in which energy is transmitted to the fluid continuously through an impeller, which imparts kinetic energy (velocity) to the fluid, which energy is then transformed into pressure in an immediately subsequent phase, thus reducing velocity.
What is positive vs dynamic pump?
Positive displacement pumps typically have higher volumetric efficiency than dynamic pumps, especially when dealing with high-viscosity fluids or high-pressure applications. Dynamic pumps may offer higher overall efficiency for low-viscosity fluids and low-pressure applications.
What are the three types of pumps?
There are three basic types of pumps: positive-displacement, centrifugal and axial-flow pumps. In centrifugal pumps the direction of flow of the fluid changes by ninety degrees as it flows over an impeller, while in axial flow pumps the direction of flow is unchanged.
What is the heart of a dynamic pump?
Working of a rotodynamic pump. Centrifugal pump is the most common used pumping device in the hydraulic world. In which the water comes from the tank at the center of the impeller and exits at the top of the pump. The impeller is called the heart of the system.
What is the function of a dynamic pump?
Dynamic pumps impart velocity and pressure to the fluid as it moves past or through the pump impeller and, subsequently, convert some of that velocity into additional pressure.