Gas turbines are responsible for powering all kinds of things around the world. You have almost certainly benefited from them numerous times, probably without consciously acknowledging it. But what exactly are gas turbines? How do they work and how can you keep them running efficiently?
Here’s a quick guide telling you everything you need to know about these amazing systems…
What is a gas turbine?
A gas turbine is used to power various things including aircraft; trains; ships; pumps; gas compressors; tanks; and electrical generators to power e.g. homes.
What are the 3 main components of a gas turbine?
How does a gas turbine work?
- Air flowing through the gas turbine compressor is brought to very high pressure.
- Fuel is combined with the high pressure air and the mix is ignited.
- The high temperature, pressurised gas then enters and drives the turbine, as it expands.
- The turbine output is used to drive the compressor to continue the process.
- Any leftover energy can be used for the purpose of the turbine e.g. rotating a second turbine connected to an electrical generator.
How does a gas turbine compressor work?
The compressor has rows of rotating and stationary blades. The rotating blades accelerate the air in both the axial and circumferential directions, while the stationary blades ensure the flow of air is redirected and prepared for the next set of rotating blades. Working together, the series of blades create a continuous flow of increasingly compressed gas.
What are the different types of gas turbine compressors?
Although all used for a similar purpose, there are different kinds of gas turbine compressor:
- axial compressor
- centrifugal compressor
- mixed flow compressor
- free-piston gas generator (combination compressor/combustion chamber in one unit)
What is the ISO rating of gas turbines?
ISO stands for International Organisation for Standardization and the ISO conditions for gas turbines are 59ºF, 14.7 pounds per square inch absolute and 60% relative humidity.
Why is air compressed in a gas turbine?
It is important to compress the air before ignition as this allows for greater expansion and a more complete, efficient combustion.
What is the difference between a gas turbine and steam turbine?
As the name suggests, steam turbines are rotated using steam. There is no compressor or combustion system in this process. Water is heated in a boiler, offering the opportunity to use a renewable energy source.
What are the fuels used in a gas turbine plant?
Although natural gas is the most common fuel for gas turbine plants they can be adapted to use almost any flammable gas or light distillate petroleum products e.g. petrol, diesel or paraffin. Crude oil and other heavy oils can even be used if they are first heated to reduce viscosity.
How to calculate gas turbine efficiency?
Efficiency is important to your operations but it can be difficult to know if your turbine is running efficiently or not. Use our tool to determine if your system could use some improvements.
Why is gas turbine efficiency so low?
As air and fuel flow through the compressor, foulants are inevitably deposited on compressor blades. When these foulants build up they interrupt airflow and compromise efficiency. If you are noticing inefficiency in your system it is worth looking at your compressor cleaning schedule.
How can you increase the efficiency of a gas turbine?
A simple, cost effective method of increasing efficiency
is to regularly cleanse away foulants from the gas turbine compressor. The hardware to complete cleans even during normal turbine operation can be retrofitted in almost every case.
What can you clean a gas turbine compressor with?
We also design and supply hardware which can usually be retrofitted. Atomised water and detergent (if desired) is sprayed directly into the compressor, effectively removing foulants and restoring a clean, efficient and productive system.