Post by GrantB on May 20, 2012 13:07:48 GMT -5
I mentioned in my intro thread that i joined to gain knowledge on turbine construction so i could build my own "hypercharger" or as i call it Gas Turbine Assist. An over simplified explanation is you have a gas turbine with 2 combustors. One in an internal combustion engine, the other is a conventional turbine combustor. MTU used this setup on some of its diesel tank engines IIRC.
Normally this is something that might be a little overkill for a race car but i believe it has a place for any kind of racing at higher altitude. Since the smaller more responsive turbos don't have a high enough pressure ratio you are left with a responsive turbo that doesn't make as much pressure as you would like. You can go bigger but that makes the car alot more difficult to drive. With GTA i hope that there will always be pressure available and it will make the drive-ability very easy and allow the motor to make alot of power.
Currently im working an alot of different aspects of the car but the only one that hasn't really gained much traction is the combustor design. I started doing some actual research and came to the conclusion that John really knows what he is doing and i'd just be wasting my time trying to design it on my own only to get mediocre results so here is the message i sent him and his reply was that he wanted it posted publicly so here it is.
So John or anyone else that has any input im all ears is designing a combustor that will work over a wide range or air flows. I have a modular design in mind so i can more easily manufacture different flame tubes and swap them in and out for testing but things like over all dimensions for the whole can would be nice.
The attached image is what i started working on but i knew it was going to be all wrong. I wanted to use a stainless cone
(4x18x2.5) I have but it just looked wrong lol. The top was going to get the fuel injectors and some holes to allow air in but why continue when you know it won't work lol.
Thanks,
Grant
Normally this is something that might be a little overkill for a race car but i believe it has a place for any kind of racing at higher altitude. Since the smaller more responsive turbos don't have a high enough pressure ratio you are left with a responsive turbo that doesn't make as much pressure as you would like. You can go bigger but that makes the car alot more difficult to drive. With GTA i hope that there will always be pressure available and it will make the drive-ability very easy and allow the motor to make alot of power.
Currently im working an alot of different aspects of the car but the only one that hasn't really gained much traction is the combustor design. I started doing some actual research and came to the conclusion that John really knows what he is doing and i'd just be wasting my time trying to design it on my own only to get mediocre results so here is the message i sent him and his reply was that he wanted it posted publicly so here it is.
Hello, i mentioned in my intro thread that i may ask for assistance in designing my combustor so here i am. I would like to experiment and try to learn from building alot of turbines but i already have to much on my plate and i'd like to have something that is a little closer to optimal the first time.
I would like to use a straight through style because i think it may give me more options when trying to package it and im assuming it will give a little more consistent combustion which could remove some variables should there be any issues.
upload.wikimedia.org/wikipedia/commons/3/37/Combustor_on_Rolls-Royce_Nene_turbojet_(1).jpg
I think i understand the basics of what helps and hurts a combustor so i don't feel i need your help on designing every little detail im just looking for ball park dimensions based on the turbo i would like to run and the conditions this turbine will be used under.
Like i mentioned in the first thread I kind of have my eye on a Borg Warner s480 due to the PR and it being able to supply right around my final goal of 800hp at 14k ft. I honestly would like something a little larger like the gt55r but cost is a concern. I work for a race team that is sponsored by BW so i can get discounted turbo parts and possibly some engineering help(im not sure if its the kind i need but its there). I also look at it that 800hp is more than the current record holder makes and if i do need more power later on down the road i can always upgrade but for right now the s480 seems like it would be PLENTY of turbo.
www.turbodriven.com/files/pdf/S400SX4-2.pdf (it is available in single scroll and i have plans to make my own light weight housing at some point)
Only other thing i can think of is it would seem that it might be good to have the combustor a little undersize to help it light off then i get off of the gas. Also if the combustor is flowing half of the air and the engine is getting half of the air i'd assume(although i really don't know) that a smaller combustor would be helpful and keep it lit and running longer. I assume if all of the air is being fed to the engine and the combustor throttle is closed(probably let a little air bleed past to prevent pooling of fuel or any vapors building up) i would shut off fuel and keep the combustor ignition going.
Im sorry if my message is confusing. I know my knowledge on this is lacking so im having a hard time expressing what i am tryig to do. basically if you can just give me some ballpark dimensions that i can start modeling up and if i can periodically send you pictures and you can comment on them i'd appreciate it. I'd just hate to put 20 hours into a model only to post it up on the forum and you or someone else saying that its horribly off lol.
I don't have a huge budget but let me know what i would owe you for your time.
Thank you,
Grant
I would like to use a straight through style because i think it may give me more options when trying to package it and im assuming it will give a little more consistent combustion which could remove some variables should there be any issues.
upload.wikimedia.org/wikipedia/commons/3/37/Combustor_on_Rolls-Royce_Nene_turbojet_(1).jpg
I think i understand the basics of what helps and hurts a combustor so i don't feel i need your help on designing every little detail im just looking for ball park dimensions based on the turbo i would like to run and the conditions this turbine will be used under.
Like i mentioned in the first thread I kind of have my eye on a Borg Warner s480 due to the PR and it being able to supply right around my final goal of 800hp at 14k ft. I honestly would like something a little larger like the gt55r but cost is a concern. I work for a race team that is sponsored by BW so i can get discounted turbo parts and possibly some engineering help(im not sure if its the kind i need but its there). I also look at it that 800hp is more than the current record holder makes and if i do need more power later on down the road i can always upgrade but for right now the s480 seems like it would be PLENTY of turbo.
www.turbodriven.com/files/pdf/S400SX4-2.pdf (it is available in single scroll and i have plans to make my own light weight housing at some point)
Only other thing i can think of is it would seem that it might be good to have the combustor a little undersize to help it light off then i get off of the gas. Also if the combustor is flowing half of the air and the engine is getting half of the air i'd assume(although i really don't know) that a smaller combustor would be helpful and keep it lit and running longer. I assume if all of the air is being fed to the engine and the combustor throttle is closed(probably let a little air bleed past to prevent pooling of fuel or any vapors building up) i would shut off fuel and keep the combustor ignition going.
Im sorry if my message is confusing. I know my knowledge on this is lacking so im having a hard time expressing what i am tryig to do. basically if you can just give me some ballpark dimensions that i can start modeling up and if i can periodically send you pictures and you can comment on them i'd appreciate it. I'd just hate to put 20 hours into a model only to post it up on the forum and you or someone else saying that its horribly off lol.
I don't have a huge budget but let me know what i would owe you for your time.
Thank you,
Grant
So John or anyone else that has any input im all ears is designing a combustor that will work over a wide range or air flows. I have a modular design in mind so i can more easily manufacture different flame tubes and swap them in and out for testing but things like over all dimensions for the whole can would be nice.
The attached image is what i started working on but i knew it was going to be all wrong. I wanted to use a stainless cone
(4x18x2.5) I have but it just looked wrong lol. The top was going to get the fuel injectors and some holes to allow air in but why continue when you know it won't work lol.
Thanks,
Grant