Oxygen fuel ratio calculations(OFC), fuel density...
12-19-2019, (Subject: Oxygen fuel ratio calculations(OFC), fuel density... ) 
Post: #1
Oxygen fuel ratio calculations(OFC), fuel density...
Was wondering if anyone can help me with the actual calculations with respect to ofc tables, trying to keep my question as general as possible:D. Thanks.
replyreply
12-19-2019, (Subject: Oxygen fuel ratio calculations(OFC), fuel density... ) 
Post: #2
RE: Oxygen fuel ratio calculations(OFC), fuel density...
the numbers u see in a calibration for ofc are partial results from a typical fuel-air-mix formula then converted to oxygen fuel control via the lambda. - Essentially most of the math is pre-calculated so that the ecm does not have to do all the math on the fly.

A person needs the correct lambda table for the engine to even start to convert the ofc table back and fourth to fuel-air-mix, so that someone can see what they re doing.

Then, there is also the 'theoretical' model vs real model ... the ecm uses the 'theoretical / stoichiometric' model, bottoming out at roughly ~14.5:1 on the high end, but the real outcome can be as much as over 400:1 depending on conditions, engine modes, torque and power, boost, etc.

some related info / example topic (is for gas engine, but is good document on the subject): https://x-engineer.org/automotive-engine...rformance/



BTW: Those tables are NOT the fuel-air-mix adjustment tables... They are the limiter only, to prevent smoke/soot production during acceleration while the turbo has not yet gotten caught up to the desired pressures. - I.E> raising the numbers a bit allows for a harder acceleration. -- Less fuel limiting during hard acceleration, only while the turbo is lagged, but it also introduces black smoke+soot, the higher it is set. - Poor fuel mileage, more soot in the oil, eventual carbon packing, etc.etc. - and on a stock (non-deleted) engine,.. a LOT more dpf and aftertreatment problems.

-- I can correctly calculate those tables. PM me, give a yell over on my mumble server, or call me (assuming you have my number) some time if you need some specific help figuring something out.


User's Signature: ->: What I post is just my own thoughts and Opinions! --- I AM Full Of S__T!.
replyreply
 Thanks given by: schISM , Nostalgic , kmk




NOTE: Rawze.com is not affiliated, nor endorses any of the google ads that are displayed on this website.