# Commission Regulation (EU) 2017/2400 of 12 December 2017 implementing Regulation (EC) No 595/2009 of the European Parliament and of the Council as regards the determination of the CO2 emissions and fuel consumption of heavy-duty vehicles and amending Directive 2007/46/EC of the European Parliament and of the Council and Commission Regulation (EU) No 582/2011 (Text with EEA relevance), Appendix 9

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

Generic model – torque converter
Generic torque converter model based on standard technology:
For the determination of the torque converter characteristics a generic torque converter model depending on specific engine characteristics may be applied.
The generic TC model is based on the following characteristic engine data:
nrated Maximum engine speed at maximum power (determined from the engine full-load curve as calculated by the engine pre-processing tool) [rpm]
Tmax Maximum engine torque (determined from the engine full-load curve as calculated by the engine pre-processing tool) [Nm]
Thereby the generic TC characteristics are valid only for a combination of the TC with an engine sharing the same specific characteristic engine data.
Description of the four-point model for the torque capacity of the TC:
Generic torque capacity and generic torque ratio:
Figure 1
Generic torque capacity
Figure 2
Generic torque ratio
where:
TP1000 Pump reference torque; TP1000=TP×1000rpmnp2 [Nm]
vSpeed ratio; v=n2n1 [-]
μTorque ratio; μ=T2T1 [-]
vs Speed ratio at overrun point; vs=n2n1 [-]
For TC with rotating housing (Trilock-Type) vs typically is 1. For other TC concepts, especially power split concepts, vs may have values different from 1.
vc Speed ratio at coupling point; vc=n2n1 [-]
v0 Stall point; v0 = 0 [rpm]
vm Intermediate speed ratio; vm=n2n1 [-]
The model requires the following definitions for the calculation of the generic torque capacity:
Stall point:
Stall point at 70 % nominal engine speed.
Engine torque in stall point at 80 % maximum engine torque.
Engine/Pump reference torque in stall point:
TP1000v0=Tmax×0,80×1000rpm0,70×nn2
Intermediate point:
Intermediate speed ratio vm = 0,6 * vs
Engine/pump reference torque in intermediate point at 80 % of reference torque in stall point:
TP1000vm=0,8×TP1000v0
Coupling point:
Coupling point at 90 % overrun conditions: vc = 0,90 * vs
Engine/pump reference torque in clutch point at 50 % of reference torque in stall point:
TP1000vc=0,5×TP1000v0
Overrun point:
Reference torque at overrun conditions = vs :
TP1000vs=0
The model requires the following definitions for the calculation of the generic torque ratio:
Stall point:
Torque ratio at stall point v0 = vs = 0:
μv0=1,8vs
Intermediate point:
Linear interpolation between stall point and coupling point
Coupling point:
Torque ratio at coupling point vc = 0,9 * vs :
μvc=0,95vs
Overrun point:
Torque ratio at overrun conditions = vs :
μvs=0,95vs
Efficiency:
n = μ * v
Linear interpolation between the calculated specific points shall be used.

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Source: https://www.legislation.gov.uk/eur/2017/2400/annex/VI/appendix/9 (the official version)
Page: https://openlegislation.uk/eu-regulation-2017-2400/annex-VI/appendix-9
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.