(a) [Reserved]
(b) Convert emission analyzer data to instantaneous concentrations in ppm (ppmC for the FID).
(c) Calculate instantaneous exhaust volumetric flow rates in standard m
3/hr (volume and density values used in these calculations are
corrected to standard conditions of 20 °C and 101.3 kPa.). Calculate exhaust
volumetric flow rate from the following equation: Exhaust volumetric flow rate = (intake air mass flow rate)(1+mass fuel/air
ratio)/(density of exhaust) (1) If you do not know the instantaneous density of the exhaust, use the
minimum density of the exhaust that occurs over the course of the test,
corrected to standard conditions.
(2) For gasoline-fueled engines designed to be operated at stoichiometric
fuel/air ratios, you may assume that the density of the exhaust is 1202 g/m
3 at standard conditions of 20 °C and 101.3 kPa.
(3) For LPG-fueled engines designed to be operated at stoichiometric fuel/air
ratios, you may assume that the density of the exhaust is 1175 g/m 3
at standard conditions of 20 °C and 101.3 kPa.
(4) For CNG-fueled engines designed to be operated at stoichiometric fuel/air
ratios, you may assume that the density of the exhaust is 1149 g/m 3
at standard conditions of 20 °C and 101.3 kPa.
(d) Calculate instantaneous emission rates (g/hr) using the following general
equation: Emission rate = (exhaust volumetric flow rate)(ppm)(density
factor)/106 Where: Density factors are 576.8 g/m3 for THC, 1913 g/m3 for
NO (e) Integrate instantaneous emission rates for the entire specified sample
period.
(f) Determine instantaneous brake torque and speed.
(g) Calculate instantaneous brake power.
(h) Integrate instantaneous brake power for the entire specified sample
period.
(i) Divide the integrated emission rates by the integrated brake power. These
are your final brake-specific emission rates.