20210727-PRESLHY_D3_5_E3_4-UNIgnitedPool

In the frame WP3.4 of the PRESLHY project 10 experiments on LH2-pool formation above
different substrates have been performed with the POOL-facility on a free field-test site located
a few kilometers to the north of KIT Campus North. Substrates to be investigated comprised
concrete, sand, water and gravel. Four of the experiments were made with artificial side wind
of known direction and known velocity to investigate the influence of side wind on the
formation and evaporation of the LH2-pools.
The POOL-facility mainly consists of an insulated stainless-steel box with the dimensions 0.5 x
0.5 x 0.2 m³ that is filled up to half the height (0.1 m) with the respective substrate. The height
of the LH2-pool that forms above the substrate can be determined using the weight of the
complete facility, since it is positioned on a scale, but also 6 thermocouples that are located in
different heights above the substrate surface clearly show a stable signal as soon as they are
covered with LH2. Further measurement equipment used in the tests comprise temperature
measurements inside the substrate and in the unconfined space above the pool, where also H2-
concentration measurements are performed.
Using the sensor information, pool formation and evaporation rates for the different substrates
could be determined. Furthermore, the temperature and concentration measurements above the
pool were used to define promising ignition positions for the experiments of WP4.4, where the
LH2-spills above the different substrates should also be ignited.