Estimated End of Combustion

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The estimated end of combustion (EEOC) is required for determining the normalising value for mass fraction burned and for heat release analysis. There have been several methods suggested by researchers, but the most common is to determine the crank angle that provides a maximum value of equation 1.

x=pV^1.15 (Equation 1)

In order to reduce the effects of signal noise, the method is modified slightly to determine the crank angle that provides a maximum over a five-point summation of equation 1:

x=sum_(i=theta-2)^(i=theta+2)p_iV_i^1.15 (Equation 2)

In order to ensure the end of combustion is not underestimated, ten degrees is added to the crank angle at which x reaches a maximum.

catool Implementation: See Return_EEOC() in analysis.c

References:

1. Brunt, M. and Emtage, A., "Evaluation of Burn Rate Routines and Analysis Errors," SAE Technical Paper 970037, 1997