Discussion on the best fuel type.

[Bhuvan Aerospace]

John Sir you are right, the mass flow of my engine is 1.02 Kg/sec due to wrong calculations I have done due to wrong assumptions of ChatGPT.

[racket]

Your assumed pressure ratio per stage is very high , it'll be closer to 1.2:1 .

[Bhuvan Aerospace]

Why will it not get high pressure ratios?

[racket]

This 91 mm inducered comp flows a lot of air www.garrettmotion.com/wp-content/uploads/2018/05/Comp-Map-GTX5533-91mm-2-scaled.jpg 1.14 kgs/sec

[Bhuvan Aerospace]

So what shall I do according to you ?

Also, anew update, I have placed order of 2 axial compressors which I have designed from PCBWAYS.

[Bhuvan Aerospace]

Now I am personally doing calculations.

M= r.A.v

So, A= pi/4. (D^2-D^2h)

= pi/4 . (0.09^2-0.05^2)

=pi/4 . (0.0056)

=0.004398

So M= 1.225x0.004398x200

M=1.08kg/sec.

Now I don’t believe ChatGPT.

[enginewhisperer]

cancel that order if you're worried about wasting money.

If it's worth the price to sit them on the shelf that's fine, but there is no way you'll build a successful engine using those parts with the amount of research you have done so far.

[enginewhisperer]

Nov 20, 2024 20:25:58 GMT -5 Bhuvan Aerospace said:

Now I don’t believe ChatGPT.

ChatGPT doesn't know anything about maths, engineering, or turbine engines. It doesn't even know about language - it generates an answer to a question based on the statistical likelihood of those words appearing.

Think of it as "this is what an answer to your question would most likely look like"


Some of it may be correct, and some of it won't be.

It might help you put together some information quickly, but it's not a substitute for understanding the basics.
There are a huge number of variables in something like a jet engine, and this is why people usually start from rules of thumb (like mass flow per area of inducer)

The rule of thumb won't be 100% accurate, but if your calculations don't roughly agree with it, your calculations are wrong.

[Bhuvan Aerospace]

Nov 20, 2024 20:26:58 GMT -5 enginewhisperer said:

cancel that order if you're worried about wasting money.

If it's worth the price to sit them on the shelf that's fine, but there is no way you'll build a successful engine using those parts with the amount of research you have done so far.

I am not worried about wasting money. The calculations for the compressors are 100% correct and it will be shipped to my home.

[Bhuvan Aerospace]

Nov 20, 2024 20:32:43 GMT -5 enginewhisperer said:

Nov 20, 2024 20:25:58 GMT -5 Bhuvan Aerospace said:

Now I don’t believe ChatGPT.

ChatGPT doesn't know anything about maths, engineering, or turbine engines. It doesn't even know about language - it generates an answer to a question based on the statistical likelihood of those words appearing.

Think of it as "this is what an answer to your question would most likely look like"


Some of it may be correct, and some of it won't be.

It might help you put together some information quickly, but it's not a substitute for understanding the basics.
There are a huge number of variables in something like a jet engine, and this is why people usually start from rules of thumb (like mass flow per area of inducer)

The rule of thumb won't be 100% accurate, but if your calculations don't roughly agree with it, your calculations are wrong.

The calculations that I have done are 100% correct and according to rule of thumb. The calculations done by the ChatGPT are wrong. That’s why now I am doing calculations.

[racket]

OK, your flow is 1.08 kgs/sec and your 6 stage axial comp is producing an 11.39 PR at 1.5:1 PR per stage , this will require your turbine wheel to produce 560 HORSEPOWER to power it .

Then you need to add on your fan power requirements , 4 kgs at say 1.5 PR , this is another 250 BHP , , so ~800 HP will be required from your turbine wheel ...........mmmmmmm, thats a fair bit from a 90 mm wheel .

[enginewhisperer]

Nov 20, 2024 20:43:48 GMT -5 Bhuvan Aerospace said:

I am not worried about wasting money. The calculations for the compressors are 100% correct and it will be shipped to my home.

You didn't want to pay the membership for GTBA and had previously said you had a low budget, so I figured you wouldn't want to waste money on parts you probably won't be able to use.

Do you have pictures of the compressor parts CAD?
What process are they being made by (CNC machining? 3D metal printing?)
What will they cost?

[Bhuvan Aerospace]

Nov 20, 2024 22:08:02 GMT -5 racket said:

OK, your flow is 1.08 kgs/sec and your 6 stage axial comp is producing an 11.39 PR at 1.5:1 PR per stage , this will require your turbine wheel to produce 560 HORSEPOWER to power it .

Then you need to add on your fan power requirements , 4 kgs at say 1.5 PR , this is another 250 BHP , , so ~800 HP will be required from your turbine wheel ...........mmmmmmm, thats a fair bit from a 90 mm wheel .

I think it can.

[Bhuvan Aerospace]

Nov 21, 2024 1:39:40 GMT -5 enginewhisperer said:

Nov 20, 2024 20:43:48 GMT -5 Bhuvan Aerospace said:

I am not worried about wasting money. The calculations for the compressors are 100% correct and it will be shipped to my home.

You didn't want to pay the membership for GTBA and had previously said you had a low budget, so I figured you wouldn't want to waste money on parts you probably won't be able to use.

Do you have pictures of the compressor parts CAD?
What process are they being made by (CNC machining? 3D metal printing?)
What will they cost?

Actually, I had a budget of ₹1,00,000 earlier. But now I have the budget of ₹2,00,000. Also the GTBA membership is very cheap. I am just waiting for March 2025. Another Thing, I manufacture the compressor by CNC Milling. I am uploading the CAD images.

[Bhuvan Aerospace]

I am sharing the Prototype axial compressor CAD Design file as I don't have the permission to share the main one.