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

3 Experiments on Droplet Array Combustion
C
B
Figure 3.5: Schematic of Droplet Generation Process. All droplets of the array are simultaneously
generated [282]. A: crossed pair of SiC fibers, B: tethered fuel droplet, C:
fuel supply through fine glass tube.
A
the fuel supply block moves forward. The fine glass tube will then bend elastically
due to the forward movement (Fig. 3.4, B - D). However, either unit being
damaged by the droplet generation process is improbable.
The fuel supply block consists of the main cuboid of aluminum with fixture
bores for the glass tubes and the glass tubes themselves. Additional drill holes
assure the internal fuel distribution within the block. Two threads, one on
each side of the block, are used to seal these fuel supply channels after manufacturing
and to bleed trapped air. In order to ensure an assembly process
without any damage to the fine glass tubes as well as a smooth operation without
blocking single glass tubes, the aluminum block had to be cleaned from
chips and manufacturing residues in an ultrasonic cleaner. By anodizing the
aluminum block and the other metallic parts within the field of view of the
droplet generation process, reflections obscuring the observation of this process
could be minimized. The high precision manufacturing process of the
fine glass tubes is outlined in Chapter C.2.
Generally, the single-part fabrication of fuel supply block and droplet array
holder implies high precision and a considerable degree of hands-on experience
for the manual labor steps. After completion of all single component
manufacturing steps, a fuel supply block is finalized by inserting the fine glass
tubes into their support and applying glue to the fitting locations. Before curing,
a correct alignment of the glass tube orifices needs to be secured. Setups
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