Turbine engine burner can hole size

AI Thread Summary
When designing a turbine engine burner can without a compressor section, the hole sizes must be based on the air pressure and flow available rather than standard formulas. The diameter of the flame tube should be twice the intake diameter, with a length six times the intake diameter, and the holes should be arranged in three rows with varying areas. The combustor design relies heavily on the specifications of the air compressor used, and achieving clean combustion requires a fuel-to-air mass ratio of 1:15, along with cooling air to protect the combustor. The size and number of holes are determined by the differential pressure and flow rate of the compressed air, while their positioning is critical for cooling and fuel injection. For further guidance, resources like Wikipedia and targeted searches on turbine combustors are recommended.
iwant2beoz
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Im building a turbine engine and I am having trouble figuring out the hole sizes for the burner can, my problem is that I am not using a compressor section but rather using an air compressor for the air intake so I can't use the standard formula, can I? If I know my blad diameter and the flow rate of the compressor can I work out the burner dimensions from that or will I have to use trial and error? That you in advance.
 
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The source of the compressed air does not matter.
What matters is the pressure of the air surrounding the combustion chamber.
Use a hole size determined by the air pressure and flow available.
 
Ok, I don't know the formula for that, do you know where I can find it?
 
iwant2beoz said:
my problem is that I am not using a compressor section but rather using an air compressor for the air intake so I can't use the standard formula, can I?
Where is, or what is the standard formula?
 
Make the diameter of the flame tube 2x the diameter of the intake, the length 6x the diameter of the intake. Make 3 rows of holes, the first 20% the area of the intake, the second 30% and the third 50%. This is the only formula can find. This is for an engine with only one burner,
 
You have not identified the scale of your implementation, such as your compressor characteristics.
Combustor design for you is now a black art, it will becomes an artistic style before it matures into a formulaic science.

You are going to have to apply a scientific approach to this engineering question.
The combustor design will be determined by the compressor operating specifications.
For clean combustion, you will require 15 times the mass of air as fuel.
Plus you need cooling air to protect the combustor from the flame.

The size of the holes will be dependent on the differential pressure across the burner wall.
The number of holes will be proportional to the flow rate of the compressed air.
The position of the holes will be dependent on the cooling, the fuel injection and ignition points.

Start with; http://en.wikipedia.org/wiki/Combustor#Air_flow_paths
It is then time to google “turbine combustor”.
 
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