# Equation of non-symmetric cone for fuel consumption maps

1. Aug 29, 2012

### aLEx7

Dear Brains

I am working on fuel consumption maps to be included in vehicle simulation software to calculate the fuel consumption. To be able to create the map you need 3 things : RPM, Engine Power, and consumption (kgr/h) or efficiency of the engine (Depending on the consumption). You take all the points and you make a graph like this when using rpm, engine power and consumption: http://www.google.it/imgres?um=1&hl=en&client=firefox-a&sa=N&rls=org.mozilla:en-USfficial&biw=1280&bih=894&tbm=isch&tbnid=lFKKLjGllcy7FM:&imgrefurl=http://pubs.ext.vt.edu/442/442-073/442-073.html&imgurl=http://pubs.ext.vt.edu/442/442-073/L_IMG_442-073-3.jpg&w=700&h=434&ei=gQo-UJiME-ja4QTU24CwBQ&zoom=1&iact=rc&dur=287&sig=101014921224332976206&page=1&tbnh=131&tbnw=211&start=0&ndsp=20&ved=1t:429,r:11,s:0,i:108&tx=133&ty=92

which is 2 polynomials equation z(x,y) (or something like this)

If you substitute the consumption with the efficiency you will get a graph like this:http://www.google.it/imgres?um=1&hl=en&client=firefox-a&sa=N&rls=org.mozilla:en-USfficial&biw=1280&bih=894&tbm=isch&tbnid=G_JtyTAq1f6S7M:&imgrefurl=http://ecomodder.com/forum/showthread.php/vvt-18559.html&imgurl=http://ecomodder.com/wiki/images/e/ee/Ford_2.0l_zetec_bsfc.JPG&w=474&h=334&ei=gQo-UJiME-ja4QTU24CwBQ&zoom=1&iact=hc&vpx=613&vpy=567&dur=8454&hovh=188&hovw=268&tx=131&ty=72&sig=101014921224332976206&page=2&tbnh=149&tbnw=211&start=20&ndsp=25&ved=1t:429,r:2,s:20,i:146

I know that here the y-axis is torque but is the same idea

This i can describe it with my little knowledge of mathematics as a non-symmetric cone. Is anyone that could give a general equation that will described this graph? I know that is not only one equation it should be multiple equations. But I can not find any info around the internet or I am really not searching well