Division 2.2.4.2: CFV-CVS system - 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

The mass flow over the cycle m _ed [g/test] shall be calculated by means of equation (7-37), if the temperature of the diluted exhaust gas is kept within ± 11 K over the cycle by using a heat exchanger:

m_{ed} = \frac{1,293 \times t \times K_{V} \times p_{p}}{T^{0,5}}

(7-37)

Where:

t

cycle time [s]

K _V

calibration coefficient of the critical flow venturi for standard conditions $[(\sqrt{K} \times m^{4} \times s) ∕ kg]$

p _p

absolute pressure at venturi inlet [kPa]

T

absolute temperature at venturi inlet [K]

1,293 kg/m³

air density at 273,15 K and 101,325 kPa

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 (7-38):

m_{ed, i} = \frac{1,293 \times Δ t_{i} \times K_{V} \times p_{p}}{T^{0,5}}

(7-38)

where:

Δt_i

time interval of the test [s]