Riello DB 4 SM BLU Installation, Use And Maintenance Instructions page 27

Air side pressure drop (taken upstream from the completely open air damper)
2.5
m bar
Fig. 7
The pressure curves refer to the different adjustment conditions for the combustion head in accordance to the table on page 12.
Refer to Paragraph 5.1.
In the case of air supply at a higher temperature than 20°C and/or an altitude higher than 100 m. a.s.l., the pressure drop in the
head that is shown in the graph must be multiplied by the K
Altitude
m. a.s.l. 0 20
0 0.920 0.988
100 0.932 1.000
500 0.976 1.047
750 1.007 1.080
1000 1.038 1.114
1250 1.069 1.147
1500 1.102 1.182
1750 1.130 1.213
2000 1.174 1.260
2250 1.206 1.294
2500 1.251 1.343
2750 1.284 1.378
3000 1.320 1.417
Example for DB 6
Burnt output = 6000 kW - Altitude = 750 m. a.s.l. - Combustive air temperature = 120 °C
From the diagram, with an output of 7000 kW, a total head pressure drop is shown of: p
and altitude 100 m. a.s.l.).
The table gives a multiplying coefficient, for combustive air at 120 °C and altitude 750 m. a.s.l., equal to K
The total pressure drop of the burner head is:
p = p
x K = 40 x 1.449 = 58 mbar.
20 c
40
35
30
25
20
15
10
5
0 1000 2000
c
30 40 50
1.021 1.055 1.089 1.122
1.034 1.069 1.103 1.137
1.083 1.119 1.155 1.190
1.117 1.154 1.191 1.228
1.152 1.190 1.228 1.266
1.186 1.226 1.265 1.304
1.223 1.263 1.304 1.344
1.254 1.295 1.337 1.378
1.303 1.346 1.389 1.432
1.338 1.382 1.427 1.471
1.389 1.434 1.480 1.526
1.425 1.472 1.519 1.566
1.465 1.514 1.562 1.610
2
CHAPTER
4000 6000
Burner output Pb
coefficient as indicated in the table below.
K
c
Air temperature °C
60 70 80 90
1.156 1.190 1.223
1.171 1.205 1.239
1.226 1.262 1.298
1.265 1.302 1.338
1.304 1.342 1.380
1.343 1.382 1.421
1.384 1.425 1.465
1.419 1.461 1.502
1.475 1.518 1.561
1.515 1.559 1.603
1.572 1.618 1.664
1.613 1.660 1.707
1.659 1.707 1.755
Burner description
D8326
8000 KW
[kW]
100 120 140
1.257 1.325 1.392
1.273 1.342 1.410
1.333 1.405 1.477
1.375 1.449 1.523
1.418 1.494 1.570
1.460 1.539 1.617
1.505 1.586 1.667
1.544 1.626 1.709
1.604 1.690 1.776
1.647 1.736 1.824
1.709 1.801 1.893
1.754 1.848 1.942
1.804 1.901 1.997
= 40 mbar (combustive air at 20 °C
20
= 1.449.
c
150
1.426
1.444
1.512
1.560
1.608
1.656
1.707
1.751
1.819
1.868
1.939
1.989
2.046
7