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

C Design Details of Experiment Equipment
portation and 18 ◦ C for preparation at the launch site. During rocket ascent
the skin temperature of the outer structure rises up to 140 ◦ C, and during reentry
it reaches approximately 200 ◦ C. Nevertheless, the temperature of the
DCU within the vacuum dome was in the order of 19 to 33 ◦ C during the experimental
phase of the TEXUS-46 flight. A temperature increase of the experiment
deck of about 6K, due to radiation and suppression of convective
cooling, was taken into account for the experiment design. An increase from
29 to 32 ◦ C was finally measured for the vicinity of the droplet array generation
device. Depending on the winter season in North Sweden, an environmental
temperature of −30 ◦ C is probable, but the payload temperature after touchdown
does not drop below 0 ◦ C in normal recovery operation, which was the
case for the TEXUS-46 mission.
C.2 Construction and Manufacturing Details
Apart from the microgravity environment itself, special design features were
incorporated in the experimental setup to provide high quality results. Special
attention was given to the droplet array generation system (Fig. 3.2, D) to
realize equal vapor distribution around each droplet as well as a symmetrical
fuel vapor layer around the axis of the droplet array.
Manufacturing of Fine Glass Tubes
The manufacturing process of the fine glass tubes that are integrated into the
fuel supply block (Fig. 3.4) can be summarized as follows. Commercially obtainable
glass tubes of 1mm outer diameter are narrowed down to pairs of
micropipettes with an outer tip diameter of approximately 40µm by a pipette
generator:
220
• Thin-walled glass capillaries of standard borosilicate glass are sorted for
outer diameters of 0.990±0.002 mm. Their nominal outer and inner diameter
is 1mm and 0.75 mm, respectively. Their length is 90mm.
• A puller is used to vertically stretch the selected glass capillaries into
pipettes by applying heat and using the gravitational force. If the heater