[7. NUMERICAL EXAMPLES U.K.
7.1. Averaging window calculations U.K.
Table 1
Main calculation settings
[g] | 610 |
Direction for averaging window calculation | Forward |
Acquisition frequency [Hz] | 1 |
Figure 6 shows how averaging windows are defined on the basis of data recorded during an on-road test performed with PEMS. For sake of clarity, only the first 1 200 seconds of the trip are shown hereafter.
Seconds 0 up to 43 as well as seconds 81 to 86 are excluded due to operation under zero vehicle speed.
The first averaging window starts at t 1,1 = 0s and ends at second t 2,1 = 524 s (Table 3). The window average vehicle speed, integrated CO and NO x masses [g] emitted and corresponding to the valid data over the first averaging window are listed in Table 4.
Figure 6
Instantaneous CO 2 emissions recorded during on-road test with PEMS as a function of time. Rectangular frames indicate the duration of the j th window. Data series named ‘Valid=100 / Invalid=0’ shows second by second data to be excluded from analysis

7.2. Evaluation of windows U.K.
Table 2
Calculation settings for the CO 2 characteristic curve
CO 2 Low Speed WLTC (P 1 ) [g/km] | 154 |
CO 2 High Speed WLTC (P 2 ) [g/km] | 96 |
CO 2 Extra-High Speed WLTC (P 3 ) [g/km] | 120 |
Reference Point | | |
---|
P 1 | | |
P 2 | | |
P 3 | | |
The definition of the CO 2 characteristic curve is as follows:
For the section ( P 1 , P 2 ):
with
and: b 1 = 154 – (– 1,543) × 19.0 = 154 + 29,317 = 183,317
For the section ( P 2 , P 3 ):
with
and: b 2 = 96 – 0,672 × 56,6 = 96 – 38,035 = 57,965
Examples of calculation for the weighing factors and the window categorisation as urban, rural or motorway are:
For window #45:
For the characteristic curve:
Verification of:
124,498 × (1 – 25/100) ≤ 122,62 ≤ 124,498 × (1 + 25/100)
93,373 ≤ 122,62 ≤ 155,622
Leads to: w 45 = 1
For window #556:
For the characteristic curve:
Verification of:
105,982 × (1 – 50/100) ≤ 72,15 ≤ 105,982 × (1 + 25/100)
52,991 ≤ 72,15 ≤ 79,487
Leads to:
w 556 = k 21 h 556 + k 22 = 0,04 · (– 31,922) + 2 = 0,723
with k 21 = 1/( tol 2 – tol 1 ) = 1/(50 – 25) = 0,04
and k 22 = k 21 = tol 2 /( tol 2 – tol 1 ) = 50/(50 – 25) = 2
Table 3
Emissions numerical data
Window [#] | t 1, j [s] | t 2, j – Δ t [s] | t 2, j [s] | [g] | [g] |
---|
1 | 0 | 523 | 524 | 609,06 | 610,22 |
2 | 1 | 523 | 524 | 609,06 | 610,22 |
… | … | | … | … | … |
43 | 42 | 523 | 524 | 609,06 | 610,22 |
44 | 43 | 523 | 524 | 609,06 | 610,22 |
45 | 44 | 523 | 524 | 609,06 | 610,22 |
46 | 45 | 524 | 525 | 609,68 | 610,86 |
47 | 46 | 524 | 525 | 609,17 | 610,34 |
… | … | | … | … | … |
100 | 99 | 563 | 564 | 609,69 | 612,74 |
… | … | | … | … | … |
200 | 199 | 686 | 687 | 608,44 | 610,01 |
… | … | | … | … | … |
474 | 473 | 1 024 | 1 025 | 609,84 | 610,60 |
475 | 474 | 1 029 | 1 030 | 609,80 | 610,49 |
| … | | … | … | … |
556 | 555 | 1 173 | 1 174 | 609,96 | 610,59 |
557 | 556 | 1 174 | 1 175 | 609,09 | 610,08 |
558 | 557 | 1 176 | 1 177 | 609,09 | 610,59 |
559 | 558 | 1 180 | 1 181 | 609,79 | 611,23 |
Table 4
Window numerical data
Window [#] | t 1,j [s] | t 2,j [s] | d j [km] | [km/h] | M CO2,j [g] | M CO,j [g] | M NOx,j [g] | M CO2,d,j [g/km] | M CO,d,j [g/km] | M NOx,d,j [g/km] | M CO2,d,cc ( ) [g/km] | Window (U/R/M) | h j [%] | w j [%] |
---|
1 | 0 | 524 | 4,98 | 38,12 | 610,22 | 2,25 | 3,51 | 122,61 | 0,45 | 0,71 | 124,51 | URBAN | – 1,53 | 1,00 |
2 | 1 | 524 | 4,98 | 38,12 | 610,22 | 2,25 | 3,51 | 122,61 | 0,45 | 0,71 | 124,51 | URBAN | – 1,53 | 1,00 |
… | … | … | … | … | … | … | … | … | … | … | … | … | … | … |
43 | 42 | 524 | 4,98 | 38,12 | 610,22 | 2,25 | 3,51 | 122,61 | 0,45 | 0,71 | 124,51 | URBAN | – 1,53 | 1,00 |
44 | 43 | 524 | 4,98 | 38,12 | 610,22 | 2,25 | 3,51 | 122,61 | 0,45 | 0,71 | 124,51 | URBAN | – 1,53 | 1,00 |
45 | 44 | 524 | 4,98 | 38,12 | 610,22 | 2,25 | 3,51 | 122,62 | 0,45 | 0,71 | 124,51 | URBAN | – 1,51 | 1,00 |
46 | 45 | 525 | 4,99 | 38,25 | 610,86 | 2,25 | 3,52 | 122,36 | 0,45 | 0,71 | 124,30 | URBAN | – 1,57 | 1,00 |
… | … | … | … | … | … | … | … | … | … | … | … | … | … | … |
100 | 99 | 564 | 5,25 | 41,23 | 612,74 | 2,00 | 3,68 | 116,77 | 0,38 | 0,70 | 119,70 | URBAN | – 2,45 | 1,00 |
… | … | … | … | … | … | … | … | … | … | … | … | … | … | … |
200 | 199 | 687 | 6,17 | 46,32 | 610,01 | 2,07 | 4,32 | 98,93 | 0,34 | 0,70 | 111,85 | RURAL | – 11,55 | 1,00 |
… | … | … | … | … | … | … | … | … | … | … | … | … | … | … |
474 | 473 | 1 025 | 7,82 | 52,00 | 610,60 | 2,05 | 4,82 | 78,11 | 0,26 | 0,62 | 103,10 | RURAL | – 24,24 | 1,00 |
475 | 474 | 1 030 | 7,87 | 51,98 | 610,49 | 2,06 | 4,82 | 77,57 | 0,26 | 0,61 | 103,13 | RURAL | – 24,79 | 1,00 |
| … | … | … | … | … | … | … | … | … | … | … | … | … | … |
556 | 555 | 1 174 | 8,46 | 50,12 | 610,59 | 2,23 | 4,98 | 72,15 | 0,26 | 0,59 | 105,99 | RURAL | – 31,93 | 0,72 |
557 | 556 | 1 175 | 8,46 | 50,12 | 610,08 | 2,23 | 4,98 | 72,10 | 0,26 | 0,59 | 106,00 | RURAL | – 31,98 | 0,72 |
558 | 557 | 1 177 | 8,46 | 50,07 | 610,59 | 2,23 | 4,98 | 72,13 | 0,26 | 0,59 | 106,08 | RURAL | – 32,00 | 0,72 |
559 | 558 | 1 181 | 8,48 | 49,93 | 611,23 | 2,23 | 5,00 | 72,06 | 0,26 | 0,59 | 106,28 | RURAL | – 32,20 | 0,71 |
7.3. Urban, rural and motorway windows — Trip completeness U.K.
In this numerical example, the trip consists of 7 036 averaging windows. Table 5 lists the number of windows classified in urban, rural and motorway according to their average vehicle speed and divided in regions with respect to their distance to the CO 2 characteristic curve. The trip is complete since it comprises at least 15 % of urban, rural and motorway windows out of the total number of windows. In addition the trip is characterised as normal since at least 50 % of the urban, rural and motorway windows are within the primary tolerances defined for the characteristic curve.
Table 5
Verification of trip completeness and normality
Driving Conditions | Numbers | Percentage of windows |
---|
All Windows |
---|
Urban | 1 909 | 1 909 / 7 036 × 100 = 27,1 > 15 |
Rural | 2 011 | 2 011 / 7 036 × 100 = 28,6 > 15 |
Motorway | 3 116 | 3 116 / 7 036 × 100 = 44,3 > 15 |
Total | 1 909 + 2 011 + 3 116 = 7 036 | |
Normal Windows |
---|
Urban | 1 514 | 1 514 / 1 909 × 100 = 79,3 > 50 |
Rural | 1 395 | 1 395 / 2 011 × 100 = 69,4 > 50 |
Motorway | 2 708 | 2 708 / 3 116 × 100 = 86,9 > 50 |
Total | 1 514 + 1 395 + 2 708 = 5 617 | ] |