turbine paper
Turbo Mini Forums

Bit of bed time reading for Paul S lol

I found chaper 8.3 interesting.


http://www.google.co.uk/url?sa=t&rct=j&q=t...NjpSoeQ&cad=rja

How did you come across this. ?

You must have to much spare time

looks interresting

If i have more toys than you when i die, I WIN

Thanks Joe.

Take me the whole holiday to get through that. Just skimmed it so far, but it looks very interesting.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Figure 3.1 is a compressor map for a turbo used on 2 litre Saab engine.

I wonder........

EDIT: Thought it might be the GT1752, but a couple of pages further on, there is reference to the TD04HL. Only found after spending some time trying to correlate the compressor map with my estimate of the Gt17 :$

Edited by Paul S on 23rd Dec, 2011.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

hmmm is that saying its a 202 bhp engine ? dont know what saab engine that is .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

My best guess would be the B204R, 150kW and fitted with the TD04:

http://en.wikipedia.org/wiki/Saab_H_engine


EDIT: just got as far as Fig 3.20 that shows 1 Bar boost, so very likley to be the B204R.

Edited by Paul S on 23rd Dec, 2011.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

transient bit at the end is good ...

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

why o why did they use a retarded-big log manifold. thats not a valid comparison, atleast not for our interests. :(

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Well, I think that it is all really about transients, specifically the boost threshold and accurate simulation.

I'm on page 120 so a bit to go yet.

He uses some strange methods though to calibrate his off-boost simluations. As I have found, the most difficult element to simulate is the turbine. He uses a turbine efficiency fudge factor at each engine speed to match up the measured and simulated outputs.

I approached this in a different manner. I found that the Gt2056 was spooling up quicker than expected (based on dyno results for a 1293 with that turbine) which told me that I had undersized the turbine, so I factored the flow data for the turbine until it looked about right. The problem is that Garrett publish very limited data for the turbine, just a pressure ratio-mass flow curve that is devoid of speed info.

When I later started playing silly-buggers with the simulation to just see what would happen with silly boost figures, I could not get the power past the maximum specified by Garrett for the turbo because the engine was being stuffed by high back pressure. As soon as I tried a GT28, the power spiralled. Hence I have some confidence from a single mass-flow scale factor rather than multiple efficiency factors.

Furthermore, the data would have come from the manufacturers test of the turbine, where they would have derived the efficiency from actual measurements of flow, pressure ratio and power output. He states quite early on in the thesis that the most difficult parameter to measure is flow. So why did he take their data as verbatim and fiddle the efficiency? I might work that out yet, but it puzzles me today.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Just got to the end.

Most informative technocal paper on turbocharging that I've ever read. Although it concentrates on transients and improving torque below 2000rpm, it discusses in detail all the major factors of turbine performance.

The last chapter is good because they put things into practise, although leave out some of the specific details.

He does fully endorsed tuned inlet and exhaust runner lengths for turbocharged engines and backs it up with real results :)

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Ive still only glanced through it, but I found it interesting that the shorter 4into1 came out better than the 4-2-1, I had two thought on this, 1 the pulses could be stronger with the 4-1, and 2 the shorter manifold could be giving up less heat and therefore energy.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."