Traduction de «Recirculation des gaz d'échappement » (Français → Anglais) :

- exhaust gas recirculation (with or without),

where G EDFW ,i = instantaneous equivalent diluted exhaust mass flow rate (kg/s) G EXHW ,i = instantaneous exhaust mass flow rate (kg/s) q i = instantaneous dilution ratio G TOTW ,I = instantaneous diluted exhaust mass flow rate through dilution tunnel (kg/s) G DILW ,i = instantaneous dilution air mass flow rate (kg/s) f = data sampling rate (Hz) n = number of measurements (b) where M f = particulate mass sampled over the cycle (mg) r s = average sample ratio over the test cycle where where M SE = sampled exhaust mass over the cycle (kg) M EXHW = total exhaust mass flow over the cycle (kg) M SAM = mass of diluted exhaust gas passing the ...[+++]particulate collection filters (kg) M TOTW = mass of diluted exhaust gas passing the dilution tunnel (kg) NOTE: In case of the total sampling type system, M SAM and M TOTW are identical.

The following formulae shall be applied: where conc e,i = instantaneous concentration of the respective pollutant measured in the diluted exhaust gas (ppm) conc d = concentration of the respective pollutant measured in the dilution air (ppm) u = ratio between density of the exhaust component and density of diluted exhaust gas, as reported in Table 4, point 2.1.2.1 M TOTW,i = instantaneous mass of the diluted exhaust gas (section 2.2.1) (kg) M TOTW = total mass of diluted exhaust gas over the cycle (section 2.2.1) (kg) DF = dilution fa ...[+++]ctor as determined in point 2.2.3.1.1.

The following formula shall be applied: (in g/test) where u = ratio between density of exhaust component and density of exhaust gas conc i = instantaneous concentration of the respective component in the raw exhaust gas (ppm) G EXHW,i = instantaneous exhaust mass flow (kg/s) f = data sampling rate (Hz) n = number of measurements For the calculation of NOx , the humidity correction factor k H , as described here below, shall be used.

2.2.1. Determination of the Diluted Exhaust Gas Flow PDP-CVS system The calculation of the mass flow over the cycle, if the temperature of the diluted exhaust is kept within ± 6 K over the cycle by using a heat exchanger, is as follows: M TOTW = 1,293 x V0 x NP x (pB - p1 ) x273 / (101,3 x T) where M TOTW = mass of the diluted exhaust gas on wet basis over the cycle V0 = volume of gas pumped per revolution under test conditions (m³/rev) NP = total revolutions of pump per test pB = atmospheric pressure in the test cell (kPa) p1 = press ...[+++]ure drop below atmospheric at the pump inlet (kPa) T = average temperature of the diluted exhaust gas at pump inlet over the cycle (K) If a system with flow compensation is used (i.e. without heat exchanger), the instantaneous mass emissions shall be calculated and integrated over the cycle.

If the composition of the exhaust gas is influenced by any exhaust after-treatment system, the exhaust sample must be taken upstream of this device in the tests of stage I and downstream of this device in the tests of stage II. When a full flow dilution system is used for the determination of the particulates, the gaseous emissions may also be determined in the diluted exhaust gas.