Hi FDS-Team,
we simulated lots of water mist in recent years. During the latest project (hot aisle spray pattern simulation in a data center), I noticed something unexpected. If the water hits components (e.g. large pipes and other components in the spray path), it can drop down from these components. But if no value for SURFACE_DIAMETER is set, the droplets use the same diameter as they had before. Meaning a 100 micrometer droplet will stay a 100 micrometer droplet.
If the air is moving below (e.g. 5 m/s), you will get a completely different distribution at the floor level or in the air volume due to this as the real droplets would be much larger and less affected by the air. I noticed you can set the SURFACE_DIAMETER manually to adjust, but doesn't it make sense to use a standard value here to get more reasonable results with the standard setting? E.G. SURFACE_DIAMETER=2000?
I have not found any discussions in Github/google groups on this, and I expect that most people in the industry are using the unset SURFACE_DIAMETER value. What do you think?
Hi FDS-Team,
we simulated lots of water mist in recent years. During the latest project (hot aisle spray pattern simulation in a data center), I noticed something unexpected. If the water hits components (e.g. large pipes and other components in the spray path), it can drop down from these components. But if no value for SURFACE_DIAMETER is set, the droplets use the same diameter as they had before. Meaning a 100 micrometer droplet will stay a 100 micrometer droplet.
If the air is moving below (e.g. 5 m/s), you will get a completely different distribution at the floor level or in the air volume due to this as the real droplets would be much larger and less affected by the air. I noticed you can set the SURFACE_DIAMETER manually to adjust, but doesn't it make sense to use a standard value here to get more reasonable results with the standard setting? E.G. SURFACE_DIAMETER=2000?
I have not found any discussions in Github/google groups on this, and I expect that most people in the industry are using the unset SURFACE_DIAMETER value. What do you think?