Traduction de «Filtre pour conduite d’échantillonnage de gaz » (Français → Anglais) :

(4) ‘dust ’ means particles, of any shape, structure or density, dispersed in the gas phase at the sampling point conditions which may be collected by filtration under specified conditions after representative sampling of the gas to be analysed, and which remain upstream of the filter and on the filter after drying under specified conditions;

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 TO ...[+++]TW = 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.

In the case of fractional sampling partial flow dilution or full flow dilution, which consists of passing through the filters only a portion of the diluted exhaust, the dilution (section 2.2, figures 11,12,13,15,16,17,19; section 2.3, Figure 20) and sampling systems usually form different units.

The flow capacity of the dilution system shall be large enough to completely eliminate water condensation in the dilution and sampling systems, and maintain the temperature of the diluted exhaust gas at or below 325 K (52 °C) immediately upstream of the filter holders.

These particulates are in each case collected by two series-mounted filters in the sample gas flow.

Start the CVS (constant volume sampler) (if not already on), the sample pumps, the temperature recorder, the vehicle cooling fan and the heated hydrocarbon analysis recorder (diesel only) (The heat exchanger of the constant volume sampler if used, should be preheated to its operating temperature.) The diesel hydrocarbon analyser continuous sample line and filter (if applicable) should be preheated to 190 °C ± 10 °C.