Division 3 DETERMINING THE COOL-DOWN CURVES AND TEMPERATURES

The cool-down curves shall be determined experimentally for the baseline vehicle engine coolant and the eco-innovation vehicle coolant. The same curves shall be applicable for vehicle variants with the same heat capacities, engine bay packaging, engine heat insulation and EST system. The experimental tests shall include continuous measurements of the representative coolant temperatures of the engine coolant and the coolant stored in the EST system by means of thermocouples at a constant ambient temperature of at least 14 °C for 24 h. The engine shall be heated up to the maximum coolant temperature before cut-off by a sufficient number of consecutive NEDC tests. After preconditioning, the ignition shall be switched off and the dash key pulled out. The car's bonnet shall be closed completely. Any artificial ventilation system inside the test cell shall be switched off.

The resulting measured cool-down curves shall be converged by the mathematical approach described by Formula 1 and Formula 2 for the engine and the EST system respectively.