ANNEX VII U.K.MEASURING METHOD TO EVALUATE COMPLIANCE WITH THE ADDITIONAL SOUND EMISSION PROVISIONS

3. ANALYSIS OF RESULTS U.K.

3.1. Determination of the anchor point for each gear ratio U.K.

For measurements in gear i and lower, the anchor point consists of the maximum sound level L_woti, the reported engine speed n_woti and vehicle speed v_woti at BB' of gear ratio i of the acceleration test in Annex II.

L_anchor,i

=

L_{woti,Annex II}

n_anchor,i

=

n_{BB,woti,Annex II}

v_anchor,i

=

v_{BB,woti,Annex II}

For measurements in gear i+1 the anchor point consists of the maximum sound level L_woti+1, the reported engine speed n_woti+1 and vehicle speed v_woti+1 at BB' of gear ratio i+1 of the acceleration test in Annex II.

L_anchor,i+1

=

L_{woti+1,Annex II}

n_anchor,i+1

=

n_{BB,woti+1,Annex II}

v_anchor,i+1

=

v_{BB,woti+1,Annex II}

3.2. Slope of the regression line for each gear U.K.

The sound measurements shall be evaluated as a function of engine speed in accordance with point 3.2.1.

3.2.1. Calculation of the slope of the regression line for each gear U.K.

The linear regression line is calculated using the anchor point and the four correlated additional measurements.

(in dB/1 000 min^-1)

With and

where n_j = engine speed measured at line BB'

3.2.2. Slope of the regression line for each gear U.K.

The Slope_k of a particular gear for the further calculation is the derived result of the calculation in point 3.2.1 rounded to the first decimal place, but not higher than 5 dB/1 000 min^–1.

3.3. Calculation of the linear sound level increase expected for each measurement U.K.

The sound level L_ASEP,kj for measurement point j and gear k shall be calculated using the engine speeds measured for each measurement point, using the slope specified in point 3.2 to the specific anchor point for each gear ratio.

For n_{BB_k,j} ≤ n_anchor,k:

L_{ASEP_k,j} = L_{anchor_k} + (Slope_{k – Y}) * (n_{BB_k,j – nanchor,k})/1 000

For n_{BB_k,j} > n_anchor,k:

L_{ASEP_k,j} = L_{anchor_k} + (Slope_k + Y) * (n_{BB_k,j – nanchor,k})/1 000

Where Y = 1

3.4. Samples U.K.

On request of the approval authority two additional runs within the boundary conditions in accordance with point 2.3 shall be carried out.