Humidity Correction for NOx. As the NOx emission depends on ambient air conditions, the NOx concentration shall be corrected for ambient air temperature and humidity by the factors KH given in the following formulae. where: A = 0.309 GFuel / GAIRD - 0.0266 B = -0.209 GFuel / GAIRD + 0.00954 T = temperatures of the air in K Ha = humidity of the intake air, g water per kg dry air: Ra = relative humidity of the intake air, % pa = saturation vapour pressure of the intake air, kPa pB = total barometric pressure, kPa For diesel engines with intermediate air cooler, the following alternative equation may be used: TSCRef = to be specified by the manufacturer TSC = Temperature of the intercooled air.
Humidity Correction for NOx. As the NOx emission depends on ambient air conditions, the NOx concentration shall be corrected for ambient air temperature and humidity by the factors KH given in the following formulae. KH = 1 + A x ( Ha - 10.71) + B x (Ta - 298) where: A = 0.309 GFuel / GAIRD - 0.0266 B = -0.209 GFuel / GAIRD + 0.00954 T = temperatures of the air in K GFUEL GAIRD = Fuel air ratio (dry air basis) Ha = humidity of the intake air, g water per kg dry air: H = 6.220 x Ra x pa pB - pa x Ra
