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

Heat Loss of Combustion Chamber
Figure D.4 shows measurements of the heat loss of the combustion chamber,
which is induced by the insertion of the cold droplet array holder into
the combustion chamber (see Chap. 3.1.3). In general, all experiment runs
unveil an identical cool-down curve. Data is again taken from the combustion
runs conducted on TEXUS-46. Operational commands as well as microswitches
control the operation of the motors and valves involved. Here,
∆t = 2.2 s passes between the indication of “shutter open” and “lifting device
up”. The event “lifting device up”, in turn, initiates the start of droplet prevaporization
(t Ψ = 0.0 s). The time between indication of “lifting device up”
and ignition is ∆t = t Ψ + 0.8 s, subject mainly to the heat-up of the ignition
wire. The associated time between indication of the heat loss and ignition is
∆t = t Ψ + 1.4 s (i.e. 6.4, 11.4, and 19.4 s). As illustrated in Figure D.4, temperature
starts to drop with the droplet array holder reaching the interior of the
combustion chamber. The mere opening of the combustion chamber shutter
does not result in a detectable temperature drop.
500
K
Time t
Temperature T
490
480
t Ψ = 5 s, near side igniter
t Ψ = 5 s, far side igniter
t Ψ = 10 s, near side igniter
t Ψ = 10 s, far side igniter
t Ψ = 18 s, near side igniter
t Ψ = 18 s, far side igniter
470
0 4 8 12 16 20 s
Figure D.4: Heat Loss of Combustion Chamber During Droplet Pre-Vaporization. The measurement
readings of the PHOENIX experiment are plotted here. Time t = t 0 corresponds
to the start of droplet pre-vaporization (t Ψ = 0.0 s).
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