On the Formation of Nitrogen Oxides During the Combustion of ...

3 Experiments on Droplet Array Combustion
Table 3.4: Overview of Utilized Camera Systems.
No. Camera system Observation Encoding Frame rate
CCD1 Sony XC-555P Droplet generation PAL 25Hz
CCD2 Sony XC-555P Combustion (“normal”) PAL 25Hz
CCD3 Sony XC-ES50 Droplet size NTSC 30Hz
HSV
KODAK Motion SR-Series
PAL
Combustion (high-speed)
NAC Memrecam Ci/RX-2
NTSC
500Hz
that are used to generally observe and evaluate the droplet generation and
combustion process [410]. CCD3 is a monochrome camera and is used to obtain
backlit images of the first droplet of the droplet array. These images in
turn are consulted to calculate the initial droplet size D 0 and the vaporization
rate k [411]. Chapter C.1 gives more detailed information on the data
acquisition and handling. Here, Figure 3.12 provides a representative outline
of droplet size and pre-vaporization, as seen through the backlit illumination.
t Ψ = 5 s:
0 s
1 s
2 s
3 s
4 s
5 s
t Ψ = 10 s:
0 s
2 s
4 s
6 s
8 s
10 s
t Ψ = 18 s:
0 s
3 s
6 s
9 s
12 s
15 s 18 s
Figure 3.12: Time Evolution of Droplet Diameter During Pre-Vaporization. The backlit images
of the monochrome camera CCD3 are consulted for monitoring the droplet
size. Illumination is provided by an LED [208, 411]. The droplets have a nominal
initial diameter of D 0,nom = 1.5 mm at t = 0s. The three initial images also show
the tip of the hot-wire igniter on their righthand side.
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