Throttle Butterfly Valve Angle And Air Flow Vs Rpm Rb25Det

[spg1122]

Hi guys,

does anyone know the different angles of the throttle butterfly valve with respect to the rpm range of the engine?

I also need to know the air flow rate with respect to the rpm of the engine.

The engine must be a rb25det, preferably running with stock turbo, stock boost and stock intake manifold.

I know most of the info can be obtained by consult software like Ecutalk, but I don't have access to a consult cable.

I need the info for some CFD work.

Any help would be much appreciated!

Sam

[Ben C34]

Just going to chuck it out there, I seriously doubt anyone would have that info,, as for 99.999% of people, it is totally useless.

[spg1122]

haha no worries. I think I'm going to approach this another way...

[Kinks]

does anyone know the different angles of the throttle butterfly valve with respect to the rpm range of the engine?

throttle angle depends on what my right foot is doing. RPM is irrelevant.

the throttle is a function of load, what are your other operating conditions? There are SO MANY variables you haven't specified it is impossible to give an answer. even assuming constant speed, what gear? (this means how fast). need a bigger throttle opening in higher gears to compensate for wind resistance on the vehicle (since higher gear will necessarily be travelling faster ie more drag).

I also need to know the air flow rate with respect to the rpm of the engine.

you can check this by datalogging consult RPM vs AFM, and then separately calibrating the AFM on a flow bench to work out airflow. That's if someone doesn't already have the calibration curve handy. But if all that is too much work, 47.

The engine must be a rb25det, preferably running with stock turbo, stock boost and stock intake manifold.

I know most of the info can be obtained by consult software like Ecutalk, but I don't have access to a consult cable.

I need the info for some CFD work.

gonna need to specify things in a lot more detail, I'm sure CFD conforms to GIGO theory (garbage in, garbage out) and if you don't specify your operating conditions accurately you've got no hope of an accurate or relevant result.

[GTSBoy]

This is funny. Unless you have a really powerful computer and a lot of experience with CFD, you are going to have a hell of a time getting the time variant solution to flow in the plenum with any CFD you can afford.

We use Ansys/CFX/Fluent for the modelling we do at work, and with a non-time varying flow case in a big industrial vessel with 5+million free form cells and a dual 12 core Xeon machine with 32GB of RAM, we're looking at 3 day solution times. Go time varying and that would blow out to a month. I would expect your solution time on a small number of cells on a small machine with time variant flow to be in the order of weeks if you do it properly. And if you don't do it properly, it's not worth doing at all.

[spg1122]

Hey guys, I'm just learning CFD at uni lol. I thought this will be an interesting thing to model, but clearly not. I think I'll just stick to the ANSYS tute question for now haha

Thanks for the replies

[GTSBoy]

Oh, it's interesting alright. Just not easy.