port area crank angle graph 1

[malbeare]

Does anyone have some sugestions on software that will produce port area crank angle or port area cylinder volume graphs.

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

 

[MikeHalloran]

You should be able to generate either one with Excel, given the cam curve, the bore and stroke and a little plane geometry.



Mike Halloran
Pembroke Pines, FL, USA

 

[Tmoose]

Is this a 2 stroke question ?

 

[malbeare]

Tmoose (Mechanical) 18 Sep 05 9:44
Is this a 2 stroke question ?
I was realy looking for something I might be able to adapt for my engine . It has elements of both two and fourstroke

http://www.jack-brabham-engines.com/

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

 

[Tmoose]

software to do this ?

http://www.chuckbunnell.com/kart/jennings/Jennings11.pdf

 

[Fathead660]

Performance Trends at performancetrends.com should be able to provide the software you need and more.

Fathead660

 

[MikeHalloran]

The 'theory' page of the JBE website offers an Excel spreadsheet for download; why not start with that?



Mike Halloran
Pembroke Pines, FL, USA

 

[malbeare]

Thankyou MikeHalloran,
I just have to update my skills a bit of find someone who can.

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

 

[MikeHalloran]

There remains this one small problem: The cams are ground with unusual profiles, but the reed valves govern what's really achieved in practice, and they're controlled by gas dynamics, not the cams. So you may need to extend the model enough to approximate the gas dynamics in order to estimate what really happens in the engine.







Mike Halloran
Pembroke Pines, FL, USA

 

[malbeare]

Mike Halloran,
You are right about the gass flows, but the upper piston is controlled by a scotch yoke small crank. not a cam.
I am reading up on proffessor Blairs thoughts in his book simulation of 4-strokes about unsteady gass flows.
Thanks
Malbeare

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

 

[MikeHalloran]

Ah. I stand corrected. I just looked at the timing diagrams, and assumed it had poppet valves.

Not so; the timing is governed by the upper piston ports, further limited by a disc valve and a reed valve, or two disc valves.

Interesting.



Mike Halloran
Pembroke Pines, FL, USA