# Commission Delegated Regulation (EU) 2017/654 of 19 December 2016 supplementing Regulation (EU) 2016/1628 of the European Parliament and of the Council with regard to technical and general requirements relating to emission limits and type-approval for internal combustion engines for non-road mobile machinery, Division 2.2.4.3: SSV-CVS system

Extent: E+W+S+N.I.

The diluted exhaust gas mass over the cycle m ed [kg/test] shall be calculated by means of equation (7-39), if the temperature of the diluted exhaust gas is kept within ± 11 K over the cycle by using a heat exchanger:
m ed = 1,293 · qV SSV · Δt
(7-39)
Where:
1,293 kg/m3 air density at 273,15 K and 101,325 kPa
Δt cycle time [s]
qV SSV air flow rate at standard conditions (101,325 kPa, 273,15 K) [m3/s]
with
q V SSV = A 0 60 d 2 v C d P p 1 T r 1,4286 p − r 1,7143 p × 1 1 − r 4 D r 1,4286 p
(7-40)
Where:
A 0 collection of constants and units conversions = 0,0056940 m 3 min × K 1 2 kPa × 1 mm 2
d V diameter of the SSV throat [mm]
C d discharge coefficient of the SSV [-]
p p absolute pressure at venturi inlet [kPa]
T in temperature at the venturi inlet [K]
r p ratio of the SSV throat to inlet absolute static pressure, 1 − Δ P P a [-]
r D ratio of the SSV throat diameter to the inlet pipe inner diameter d D [-]
If a system with flow compensation is used (i.e. without heat exchanger), the mass of the diluted exhaust gas m ed, i [kg] during the time interval shall be calculated by means of equation (7-41):
m ed, i = 1,293 · qV SSV · Δt i
(7-41)
Where:
1,293 kg/m3 air density at 273,15 K and 101,325 kPa
Δti time interval [s]
qV SSV volumetric flow rate of the SSV [m3/s]

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Source: https://www.legislation.gov.uk/eur/2017/654/annex/VII/division/2/division/2.2/division/2.2.4/division/2.2.4.3 (the official version)
Page: https://openlegislation.uk/eu-regulation-2017-654/annex-VII/division-2/division-2.2/division-2.2.4/division-2.2.4.3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.