Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How to determinate instantaneus torque

  1. Jul 23, 2010 #1
    Hi guy, sorry for my english

    I've to determinate a math equation to describe the real instantaneus torque aboute a v12 diesel engine

    I've this input, the nominal torque 400 Nm at 1400 rpm, ?irregular degree?=0.05

    like this figure

    [PLAIN]http://www.epi-eng.com/images/Engine/ET-X-V12.gif [Broken]

    thanks to all

    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jul 23, 2010 #2


    User Avatar
    Science Advisor
    Gold Member

    Tricky one.

    I would model this by using cylinder pressure curves to calculate instantenous force on the connecting rod, and geometrically convert this into a torque. Overlay this for each cylinder. That gives you the firing input. You might then want to make some assumptions about torsional vibration if you have information about crankshaft stiffnesses and rotating inertias.
  4. Jul 23, 2010 #3
    Hi dot_francesco,

    I think I could help if you give me more data. We need to give me the following parameters: compression ratio [-], nominal power[kW] and the speed power[rot/min].
  5. Jul 23, 2010 #4
    this is a pubblic data sheet take from marine.cummins.com

    the V angle is 60°

    thanks to all!

    Attached Files:

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook