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Automotive CI engine performance test

  1. Sep 17, 2012 #1
    why the mechanical efficiency and brake thermal efficiency curve increases as load increases and reaches a maximum value and then again decreases( in contand speed test)
  2. jcsd
  3. Oct 2, 2012 #2
    Because with more load at a constant speed you have a wider throttle opening, an engine is at best efficiency when completely un-throttled.
  4. Oct 16, 2012 #3
    Are you saying that across the board? It seems to me that you would be more or less looking a bell curve for this efficiency. It seems that the thermal efficiency is going to decrease at a near exponetial rate as the power increases.
  5. Oct 18, 2012 #4
    Volumetric efficiency tends to fall as speed rises, if that is what you mean?
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