Turbine side in depth

Leiffi said:
Problem with V8s is pulses are not equally timed, so they will never be as efficient as inline 6.
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Okay... that's a topic for another thread.

I just want an answer to the questions asked.... nothing else.
 
he doesnt want bro science but thinks sizes are the most important factor rather than design...
 
zfaylor said:
he doesnt want bro science but thinks sizes are the most important factor rather than design...
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I've got physics books, fluid dynamic books, and engineers who pick out turbos for OEMs that all say the exducer opening and volume before the opening effect the max pressure spike and dwel period before exhaust valve close and pressure drop after.

We all know know wheel design and scroll shape matters. That's just as important to me, but why can't I also know about size correlations when it comes to pulse volumes and speeds?

Will it hurt me to know...?
 
CHDiesel said:
I didn't start this thread just to find a turbo, or I wouldnt have just asked that. I'm curious what is going on in the turbine of a turbo, and how different things effect that.
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The turbine spins.......

The man from across the pond answered your question!

The only way to stay on top of a charger with a V design as efficiently as an inline would be a cross bank manifold design similar to what's found on BMW twin turbo motors. It minimizes turbulance while increasing spool from equal pulses do to the runners feeding the turbos in firing order.

turbo5.jpg
 
blackmega3500 said:
The turbine spins.......

The man from across the pond answered your question!

The only way to stay on top of a charger with a V design as efficiently as an inline would be a cross bank manifold design similar to what's found on BMW twin turbo motors. It minimizes turbulance while increasing spool from equal pulses do to the runners feeding the turbos in firing order.

turbo5.jpg
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K... I'm not looking for how to use the exhaust pulses more efficiently. A few other brands use a flatplane crank to even out the V8 pulses though. The firing order of Duramax and PStroke just needs a single crossover from each bank.

Give me the pulse volume, gas velocity, A/R volume, peak pressure, pressure dwell time in degrees, outlet flow at exhaust density for different outlet sizes, straight scroll angle. I'll do the math myself, those are the only things I want out of this thread.

I was hoping some people already had, and they would be the ones to chime in.
 
CHDiesel said:
K... I'm not looking for how to use the exhaust pulses more efficiently. A few other brands use a flatplane crank to even out the V8 pulses though. The firing order of Duramax and PStroke just needs a single crossover from each bank.

Give me the pulse volume, gas velocity, A/R volume, peak pressure, pressure dwell time in degrees, outlet flow at exhaust density for different outlet sizes, straight scroll angle. I'll do the math myself, those are the only things I want out of this thread.

I was hoping some people already had, and they would be the ones to chime in.
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Wow!

If this much thought was put into diesel performance back in the day we'd still be talking about how awesome 700hp and 12s are....

Good luck!
 
CHDiesel said:
So what I want to know is what hot side flow ratings are enough for what horsepower levels.
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The turbine simply needs to be able to support the compressor capable of providing enough flow for the desired power. The question as posed cannot be answered, as the turbine flow itself has no direct relationship to power, and the criteria is far too vague/broad.

CHDiesel said:
Also turbine specs in relation to compressor specs is topic for another thread.
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No, it's a topic for this thread. The compressor/turbine relation not only dictates power capability but also what engine speed or range is appropriate based on the swept volume of different examples.
 
CHDiesel said:
K... I'm not looking for how to use the exhaust pulses more efficiently. A few other brands use a flatplane crank to even out the V8 pulses though. The firing order of Duramax and PStroke just needs a single crossover from each bank.

Give me the pulse volume, gas velocity, A/R volume, peak pressure, pressure dwell time in degrees, outlet flow at exhaust density for different outlet sizes, straight scroll angle. I'll do the math myself, those are the only things I want out of this thread.

I was hoping some people already had, and they would be the ones to chime in.
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The only people that have all of that information, at least to any degree of accuracy, is the OEMs. Even if you got that info, you wouldn’t be able to do anything useful with it with textbook equations. The stuff you can calculate by hand are very simple models that make a ton of assumptions and the margin of error would be so high you’d basically be guessing anyway.

There is a reason why CFD software like ANSYS costs thousands and thousands of dollars and modeling anything as complicated as turbomachinery was a graduate level mech E course.

Until recently, this industry was basically all trial and error. “Hey let’s make a 5 blade turbo instead of 7 and change the blade angle a bit and see how it does on the dyno” kind of stuff. Wagler and similar dudes have opened up the structural analysis a lot which allows you to test dozens of designs on a computer before picking the best one and saving a ton of time/money. But CFD analysis for dynamic geometries/velocities is few and far between.
 
Do you have this book: Turbocharging fundamentals , by Nicholas C. Baines ? I recommend it, lots about turbines also, but very advanced theory, I understand maybe 50% of it but it helped a lot to understand turbocharging.
 
Leiffi said:
Do you have this book: Turbocharging fundamentals , by Nicholas C. Baines ? I recommend it, lots about turbines also, but very advanced theory, I understand maybe 50% of it but it helped a lot to understand turbocharging.
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Great book! This guy wants spoon fed specific useless information zero people on this site have though.

OP none of this matters. As straight 6 said you will have yo make a lot of assumptions with any equation you use as you nor anybody else will have the numbers you need. It isn't about what's great in paper anyways. Real world testing is far more important. It's rare that an engineer gets it right 100% out of the gate. They test and analyze data and tweak.
 
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