Division 2: DETERMINING THE COOL-DOWN CURVES - Commission Implementing Decision of 10 September 2013 on the approval of the Daimler engine compartment encapsulation system as an innovative technology for reducing CO2 emissions from new passenger cars pursuant to Regulation (EC) No 443/2009 of the European Parliament and of the Council (Text with EEA relevance) (2013/451/EU)

The cool-down curves shall be determined experimentally for the baseline and the eco-innovation vehicle. The curves shall be applicable for vehicle variants with the same heat capacities, engine bay packaging and engine heat insulation as those available in the baseline and EI vehicle. The experimental test shall include continuous measurements of representative coolant temperatures by means of a thermocouple at a constant ambient temperature of at least 14 °C over 24 hours. The engine shall be heated up to the maximum coolant temperature before cut-off by a sufficient number of consecutive New European Driving Cycles (NEDC) as specified in point 3.

After preconditioning, for deactivation of all pumps and fans, the ignition shall be switched off and the dash key pulled out. The car’s bonnet shall be closed completely. Any artificial ventilation systems inside the test cell shall be switched off. The resulting measurement curves shall be converged by the mathematical approach described by formula 1.

Formula 1: $T (t) = (T_{0} - T_{A}) \times e^{(- d \times t)} + T_{A}$

with:

T(t)

temperature over time [°C]

T_O

temperature of the operating engine [°C]

T_A

ambient temperature [°C]

d

decay constant [1/h]

The least squares method shall be used for the fitting of the two curves. To do that, the temperature measurement data of the first 20 minutes after engine cut-off is not to be considered because of the untypical behaviour of the coolant temperature after switching off the coolant system.

Division 2 DETERMINING THE COOL-DOWN CURVES