A turbo pump propels. Oh yes, it does. With a rotodynamic pump and a driving gas turbine, it might propel even you up Mt. Everest! On a serious note though; a turbo is one powerful pump which produces a high-pressure fluid in a combustion chamber.
How do they work?
Gas molecules can be made to shoot off in an anticipated direction by repeated contact with a solid surface within a confined space in order to create a vacuum.
Types of turbopumps
There are two types:
- Centrifugal pump
- Axial-flow pump:
Most of the turbopumps in existence are in this group.
- Centrifugal means that the fluid is propelled into the pump via the axis and the motor speeds it up.
- It then goes through what is known as a diffuser.
- A diffuser is a pipe which gradually increases in size. The increase in size allows for the recovery of the dynamic pressure.
The diffuser converts the high kinetic energy into high pressure.
Turbopumps are not very easy to design, especially with regard to excellence in performance. This can be a problem when it comes to performance in, say, rockets. Rockets mustperform at exceedingly high levels because of the intricacies involved in their operations. A bigger percentage of the total cost of making turbopumps is invested in making pumps for rockets.
Some of the difficulties are:
- Too much flow-back from the high-pressure rim to the low-pressure rim
- A lot of recirculating of the liquid at the inlet
- The design of the rotor
- Too much whirling of the liquid as it flows from the pump casing
- Cavitation that is injurious to the impeller blade in low-pressure zones
Axial-flow turbo Pumps
They may not be as widely available as the centrifugal ones, but you can still find a few.
- It has propellers joined to the shaft.
- The fluid is propelled by them with the axis of the shaft.
- They have lower force capabilities than centrifugal pumps.
- They work as inducers for centrifugal pumps. This means that they increase the force of the centrifugal pump in order to prevent cavitation.
In what machines are turbopumps used?
- Steam turbine powered turbopumps are used in boilers and steamships; basically where there is steam.
- Gas turbine turbopumps are needed when you cannot find either steam or electricity. Place and restrictions on weight are also a major consideration with gas turbines. It is necessary for huge liquid rockets because of the high pressure that is needed and the weight of the tanks.
- Ramjet motors also require turbopumps because they drive the turbine either directly externally by free-flowing ram air or internally by air redirected from the combustor entry. The turbine exhaust is thrown out of the rocket once this is done.
There is a large enough turbo pump collections catalogue out there in the market for you to find for those humongous engines and vehicles that need to be fitted with them and the stockists have highly skilled personnel to give you practicaladvice on maintenance and to do the fitting.