Crank/valve train model 2

[SMUG]

All

What are the industry standard softwares for crank/valve train modelling for automotive engines?

Has anybody evaluated these tools?

What are the limitations on these??

 

[doctorpipe]

You may want to check out Audie Technology's Valve Pro. It is a valve train modeling program. Got to

http://www.audietech.com

for free demo's.
Doc

 

[facty]

The main drawback with the "Valve Pro" is that it doesn't perform dynamic analyses of the valvetrain. It can predict valvelifts, given a cam profile, for different valvetrains and it can produce "kinematic" data, but it cannot simulate separation and bounce of the valvetrain components in the true dynamic sense.

The other valvetrain analyses packages already mentioned in the previous replies (such as the 4stHEAD, Valdyn, GT-VTrain softwares etc) simulate full dynamic analyses of the valvetrains.

A very interesting outcome of a dynamic valvetrain analyses on a NASCAR exhaust valvetrain has shown that actual valve opening can be retarded by up to 10 degrees cam rotation due to the in-cylinder pressures and the flexibility of the particular pushrod system. No Spintron testing will ever show this to the engine designer!! (It can be validated by looking at the output from pressure transducers in the primaries)

 

[GregLocock]

Torsion in the camshaft also has interesting effects. We found this out the hard way when the indexing on a cam grinder screwed up, giving us cams with built in twist. Once we sorted that out it became apparent that some chracteristics of the engine, even with good camshafts, were similar.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[crysta1c1ear]

I spoke to somebody from a transmission company that was involved in design of powershift transmissions. He was saying that the twist in shafts is lost during a normal gearchange and has to be rebuilt when the next gear is selected. For most applications that doesn't matter, but he referred to forumla one racing, where any small differences are measured and accounted for.
He told me that the total twist in shafts etc from engine to wheels could total 360 degrees in a formula one car that had to be re-wound up after a gear change.