compressors and turbines and housings oh my. WTF is going on !
12-23-2003, 09:59 PM
#11
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Re:compressors and turbines and housings oh my. WTF is going on !
Originally Posted by stretch-d
A/R =
The "A" is the AREA or size of the opening at the end of the turbine housing where the exhaust gasses exit into the turbine blades.
The "R" is the RADIUS of the turbine housing measured by the distance from the center of the turbine shaft at a given position on the turbine housing.
The "A" is the AREA or size of the opening at the end of the turbine housing where the exhaust gasses exit into the turbine blades.
The "R" is the RADIUS of the turbine housing measured by the distance from the center of the turbine shaft at a given position on the turbine housing.
So while what your saying is technically tue. your also missing the larger point of the post. its actually
a /r is actually a equation of
Area / radious or
If the housing is 3CMsq then
it would be 3cmsq divided by the radious of the wheel would be the A/R
in this case lets say the wheel is
50mm in diameter
so the radious is 25mm or 2.5cm
if we had a Area of 3CM sq then the a/r would be
0.83 a/r
there interelated not at all seperate. And thats why its so important to understand these things.
12-23-2003, 10:09 PM
#12
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Re:compressors and turbines and housings oh my. WTF is going on !
The A/R has nothing to do with the turbine rotor or "wheel". It's the shape of the housing.
The size of the turbine rotor effects the "gearing" of the compressor wheel. A small turbine rotor will spin faster with a given amount of ehaust energy in comparison to a large one.
Effenciency has to do with how hard the compressor has to work
to create a certain amount of boost pressure.
All these dfferent combos are availible to allow the turbo system designer
to keep max effenciency in a desired rpm range(of the engine), inlet charge temp. and correct airflow for the engine.
The size of the turbine rotor effects the "gearing" of the compressor wheel. A small turbine rotor will spin faster with a given amount of ehaust energy in comparison to a large one.
Effenciency has to do with how hard the compressor has to work
to create a certain amount of boost pressure.
All these dfferent combos are availible to allow the turbo system designer
to keep max effenciency in a desired rpm range(of the engine), inlet charge temp. and correct airflow for the engine.
12-24-2003, 07:45 AM
#14
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Posts: 9,089
Re:compressors and turbines and housings oh my. WTF is going on !
again.. sean.. you are a very smart guy.. but stretch-d is correct. I just read that article of understanding turbo #'s in SCC. Older issue, but he more or less had the exact wording down.
It also states if you divide the .60/.63 or .43/.48 or whatever the hell the numbers are you should always get the same #.
It also states if you divide the .60/.63 or .43/.48 or whatever the hell the numbers are you should always get the same #.
12-24-2003, 01:17 PM
#15
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Re:compressors and turbines and housings oh my. WTF is going on !
Originally Posted by stretch-d
I'm not trying to stir anything up with my posts. I'm sure that we are very much alike... but, I would like to ask if you've read chapter three of Max. Boost?
Also the size of the exducer on the turbine wheel does directly affect the Radious of the housing. As there are not one but serval types of turbine wheels all having different circufrences and consequnetly raidious !
as i siad. Corcky beel understate the relationship has for yrs. That book has been a constant thorn in my side for a long time. a/r is a Ratio of area to radious.
12-24-2003, 01:20 PM
#16
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Re:compressors and turbines and housings oh my. WTF is going on !
Originally Posted by stretch-d
The A/R has nothing to do with the turbine rotor or "wheel". It's the shape of the housing.
The size of the turbine rotor effects the "gearing" of the compressor wheel. A small turbine rotor will spin faster with a given amount of ehaust energy in comparison to a large one.
Effenciency has to do with how hard the compressor has to work
to create a certain amount of boost pressure.
All these dfferent combos are availible to allow the turbo system designer
to keep max effenciency in a desired rpm range(of the engine), inlet charge temp. and correct airflow for the engine.
The size of the turbine rotor effects the "gearing" of the compressor wheel. A small turbine rotor will spin faster with a given amount of ehaust energy in comparison to a large one.
Effenciency has to do with how hard the compressor has to work
to create a certain amount of boost pressure.
All these dfferent combos are availible to allow the turbo system designer
to keep max effenciency in a desired rpm range(of the engine), inlet charge temp. and correct airflow for the engine.
To small of a turbine housing will just make the engine strangle itself to death.
thats the point of this post.
12-24-2003, 02:09 PM
#17
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Posts: 55
Re:compressors and turbines and housings oh my. WTF is going on !
I understand the point of the post and the information (most 
) in it. Now my question is application. With this information, how can it be applied by the thirsty minds of those putting together their "well assembled" turbo setups?
BTW sean, have you been drinking on christmas eve, or are you just typing really fast
) in it. Now my question is application. With this information, how can it be applied by the thirsty minds of those putting together their "well assembled" turbo setups? BTW sean, have you been drinking on christmas eve, or are you just typing really fast
12-24-2003, 02:59 PM
#18
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Re:compressors and turbines and housings oh my. WTF is going on !
Both drinking and typing fast. I cant answer how aplication friendly this info is just yet becuae i cant get the remaining hot side info out of there engineering dpartment as of this moment. When i do ill be glad to pass it on.
12-24-2003, 06:58 PM
#19
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Re:compressors and turbines and housings oh my. WTF is going on !
I thought the point of your post was to educate people about the subject of A/R.
You used the term "aspect ratio" to define A/R. This is simply not correct. As you refer to this in later posts, you changed your description of the term to "area & radius".
Furthermore, The radius of the Exducer does indeed effect the radius of the housing but...as a whole. It doesn't mean a change in ratio or relationship of the area to radius. You can have a larger turbo with a larger turbine rotor and still have the same ratio as on a smaller turbo with a smaller turbine rotor.
All of the info on calculating which turbo will suit your needs can be found in the pages of Max. Boost along with a wealth of other important design info. I would hardly call this book a thorn in one's side.
The point of this post is to say," If you're going to take the stance of being an educator, be sure to get every piece of info correct." Merry Christmas
You used the term "aspect ratio" to define A/R. This is simply not correct. As you refer to this in later posts, you changed your description of the term to "area & radius".
Furthermore, The radius of the Exducer does indeed effect the radius of the housing but...as a whole. It doesn't mean a change in ratio or relationship of the area to radius. You can have a larger turbo with a larger turbine rotor and still have the same ratio as on a smaller turbo with a smaller turbine rotor.
All of the info on calculating which turbo will suit your needs can be found in the pages of Max. Boost along with a wealth of other important design info. I would hardly call this book a thorn in one's side.
The point of this post is to say," If you're going to take the stance of being an educator, be sure to get every piece of info correct." Merry Christmas
12-24-2003, 11:02 PM
#20
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Join Date: Oct 2003
Posts: 232
Re:compressors and turbines and housings oh my. WTF is going on !
Originally Posted by stretch-d
I thought the point of your post was to educate people about the subject of A/R.
You used the term "aspect ratio" to define A/R. This is simply not correct. As you refer to this in later posts, you changed your description of the term to "area & radius".
Furthermore, The radius of the Exducer does indeed effect the radius of the housing but...as a whole. It doesn't mean a change in ratio or relationship of the area to radius. You can have a larger turbo with a larger turbine rotor and still have the same ratio as on a smaller turbo with a smaller turbine rotor.
All of the info on calculating which turbo will suit your needs can be found in the pages of Max. Boost along with a wealth of other important design info. I would hardly call this book a thorn in one's side.
The point of this post is to say," If you're going to take the stance of being an educator, be sure to get every piece of info correct." Merry Christmas
You used the term "aspect ratio" to define A/R. This is simply not correct. As you refer to this in later posts, you changed your description of the term to "area & radius".
Furthermore, The radius of the Exducer does indeed effect the radius of the housing but...as a whole. It doesn't mean a change in ratio or relationship of the area to radius. You can have a larger turbo with a larger turbine rotor and still have the same ratio as on a smaller turbo with a smaller turbine rotor.
All of the info on calculating which turbo will suit your needs can be found in the pages of Max. Boost along with a wealth of other important design info. I would hardly call this book a thorn in one's side.
The point of this post is to say," If you're going to take the stance of being an educator, be sure to get every piece of info correct." Merry Christmas
the a/r is techincally an apsect ratio for all intensive purposes.
As for your commects. As the diamter of the Wheel goes up the radious gets larger as does the. The Radious of the curvature of the wheel also changes as the wheel or Exducer get larger.
his has an over all effect on the actual A/r of the turbine hosuing.
Also note that there are sevral combinations of exducer wheel and turbine housing for each exducer wheel.ie
for stage 1 wheels there is .48 .63.
for stage 2 wheels there is
.48 .63 .80
for stage 5 whesl there is
.48 ( turbonteics part ) .63 .80 1.00
Maybe you shouldnt take everything you read in maximum boost ( read the disclaimer at the front ) so highly regarded.
