Division 2.3.2.2 Calculation of the particulate mass flow rate

United Kingdom

The particulate emission flow rate over the cycle q _mPM [g/h] shall be calculated by means of equations (7-53), (7-56), (7-57) or (7-58):

(a)

For the single-filter method

$q_{m PM} = \frac{m_{f}}{m_{sep}} \times \bar{q_{m edf}} \times \frac{3600}{1000}$	(7-53)
$\bar{q_{m edf}} = \sum_{i = 1}^{N} q_{m edf i} \times {WF}_{i}$	(7-54)
$m_{sep} = \sum_{i = 1}^{N} m_{sep i}$	(7-55)

Where:

q_m _PM

particulate mass flow rate [g/h]

particulate mass sampled over the cycle [mg]

\bar{q_{m edf}}

average equivalent diluted exhaust gas mass flow rate on wet basis [kg/s]

q_m

_edf

equivalent diluted exhaust gas mass flow rate on wet basis at mode i [kg/s]

WF_i

weighting factor for the mode i [-]

_sep

mass of diluted exhaust gas passing the particulate collection filters [kg]

_sep

mass of diluted exhaust gas sample passed through the particulate sampling filter at mode i [kg]
number of measurements [-]

(b)

For the multiple-filter method

q_{m PM i} = \frac{m_{f i}}{m_{sep i}} \times q_{m edf i} \times \frac{3600}{1000}

(7-56)

Where:

q_m _PM _i

particulate mass flow rate for the mode i [g/h]

m _f _i

particulate sample mass collected at mode i [mg]

q_m _edf _i

equivalent diluted exhaust gas mass flow rate on wet basis at mode i [kg/s]

m _sep _i

mass of diluted exhaust gas sample passed through the particulate sampling filter at mode i [kg]

The PM mass is determined over the test cycle by summation of the average values of the individual modes i during the sampling period.

The particulate mass flow rate q_m _PM [g/h] or q_m _PM _i [g/h] may be background corrected as follows:

(c)

For the single-filter method

q_{m PM} = \{\frac{m_{f}}{m_{sep}} - [\frac{m_{f,d}}{m_{d}} \times \sum_{i = 1}^{N} (1 - \frac{1}{D_{i}}) \times {WF}_{i}]\} \times \bar{q_{m edf}} \times \frac{3600}{1000}

(7-57)

Where:

q_m _PM

particulate mass flow rate [g/h]

m _f

particulate sample mass collected [mg]

m _sep

mass of diluted exhaust gas sample passed through the particulate sampling filter [kg]

m _f,d

particulate sample mass of the dilution air collected [mg]

m _d

mass of the dilution air sample passed through the particulate sampling filters [kg]

D_i

dilution factor at mode i [see equation (7-28) of point 2.2.2.2] [-]

WF_i

weighting factor for the mode i [-]

\bar{q_{m edf}}

average equivalent diluted exhaust gas mass flow rate on wet basis [kg/s]

(d)

For the multiple-filter method

q_{m PM i} = \{\frac{m_{f i}}{m_{sep i}} - [\frac{m_{f,d}}{m_{d}} \times (1 - \frac{1}{D})]\} \times \bar{q_{m edf i}} \times \frac{3600}{1000}

(7-58)

Where:

q_m _PM _i

particulate mass flow rate at mode i [g/h]

m _f _i

particulate sample mass collected at mode i [mg]

m _sep _i

mass of diluted exhaust gas sample passed through the particulate sampling filter at mode i [kg]

m _f,d

particulate sample mass of the dilution air collected [mg]

m _d

mass of the dilution air sample passed through the particulate sampling filters [kg]

dilution factor [see equation (7-28) of point 2.2.2.2] [-]

q _medf _i

equivalent diluted exhaust gas mass flow rate on wet basis at mode i [kg/s]

If more than one measurement is made, m _f,d/m _d shall be replaced with $\bar{m_{f,d} ∕ m_{d}}$ .