Conrod

[benberger15]

I'm currently studying motorsport engineering at swansea.

I was wondering if anyone could help me with a report I have been set.

I am required to find out the dynamic forces that a typical formula 1 conrod undergoes and how these forces affected by engine speed, reciprocating mass, stroke and ratio between conrod length and crank radius.

Any help that you can provide would be excellent!

[Brian.G]

I dont think the forum does homework answers. But I could be wrong,

Brian,

[Belatti]

Sorry, but what kind of teacher can ask you to find all that instead of actually teaching it?

[Brian.G]

Sorry, but what kind of teacher can ask you to find all that instead of actually teaching it?

Or how about wanting to find it all out yourself so that you understand it...he must have missed the three yrs prior to the report...

[bhall]

I love the condescension that gets doled out with (or in lieu of) a lot of the help around here.

[Brian.G]

I love the condescension that gets doled out with (or in lieu of) a lot of the help around here.

http://emweb.unl.edu/Mechanics-Pages/Lu ... s%20VI.htm
http://www.forging.org/fierf/pdf/dynami ... alysis.pdf
http://library.utem.edu.my/index2.php?o ... Itemid=208
http://books.google.ie/books?id=PjphGI1 ... es&f=false
http://www.eng-tips.com/viewthread.cfm?qid=115058
http://www.eng-tips.com/viewthread.cfm?qid=67425
http://www.eng-tips.com/viewthread.cfm?qid=84032
http://www.eng-tips.com/viewthread.cfm?qid=246316
http://www.eng-tips.com/viewthread.cfm?qid=246316
http://www.eng-tips.com/viewthread.cfm?qid=304710
http://www.eng-tips.com/viewthread.cfm?qid=19615

The problem lies with the question, not the answers. Its a vast subject.

Brian,

[throwaway1]

I'm currently studying motorsport engineering at swansea.

I was wondering if anyone could help me with a report I have been set.

I am required to find out the dynamic forces that a typical formula 1 conrod undergoes and how these forces affected by engine speed, reciprocating mass, stroke and ratio between conrod length and crank radius.

Any help that you can provide would be excellent!

First you need the stroke, bore, and rod length. With that you can calculate the piston's position at any point in a cycle. Using that calculate the velocity at a given rpm. Take that derivative for acceleration. With that and the piston's mass you can figure out some of the forces. The rest is a bit more complicated and you need to read up on it.

[akbar21881]

I'm currently studying motorsport engineering at swansea.

I was wondering if anyone could help me with a report I have been set.

I am required to find out the dynamic forces that a typical formula 1 conrod undergoes and how these forces affected by engine speed, reciprocating mass, stroke and ratio between conrod length and crank radius.

Any help that you can provide would be excellent!

I can't give the exact answer. But your question here is what the powertrain design engineer do in the early stage of the conrod design, to basically size the conrod as well as its small end and big end bearing, shank cross section size etc..

Basically, the thing to do after the geometric and inertia of the component has been determine is to estimate the cylinder pressure. This will then give you the force on the conrod for a given crank angle.

This should provide the clue in looking for the related equation typically used in classical method in sizing up the conrod. I'm quite rusty with the formula as I have left my powertrain CAE engineer job for almost year now!

[johnny comelately]

Hoping this is a good enough spot for (From - https://twitter.com/CalumDouglas1):
Toyota @F1 Connecting Rod - 2008 car. Next to it, Daimler-Benz DB601 connecting rod, from #WW2, 1940 Messerschmitt 109. The F1 part is about 4x smaller, but conceptually how much have we been able to advance on it ? - not much...

[63l8qrrfy6]

Pretty accurate.
Calum and I were colleagues for a year or so. He now spends his time researching and writing a book (maybe more) on WW2 engines.

He is a brilliant engineer and has put an incredible amount of effort into documenting aero engine development throughout WW2.

[strad]

I'm not a math whiz that can hand you the answers but I can bet that there are formulas available and that the teacher wants you to use those to find the answer yourself.

[godlameroso]

7 years too late I'm guessing by now he's either got a career in the industry, or hanging out at home.

[johnny comelately]

Sorry for not being clear (about dates) , just trying to stay within the correct subject thread topic post system.

[gruntguru]

I'm currently studying motorsport engineering at swansea.

I was wondering if anyone could help me with a report I have been set.

I am required to find out the dynamic forces that a typical formula 1 conrod undergoes and how these forces affected by engine speed, reciprocating mass, stroke and ratio between conrod length and crank radius.

Any help that you can provide would be excellent!

The dynamic forces you will have to calculate yourself.

The static force due to cylinder pressure is in this forum somewhere but the units are rather odd (elephants???)

[63l8qrrfy6]

I know the original topic is a bit old but since it has been resurrected here's an interesting bit of trivia:

Most companies that manufacture connecting rods and swear by either I beam or H beam sections have no clue whatsoever what the bending moments on the rod are. They design the rods purely based on tensile and compressive loads which produce shank stresses independent of the second moment of area.

Of course bending stresses are negligible in all but the highest revving engines yet there is such a debate about I vs H section when really in 90% of the cases it is nothing but a marketing gimmick.