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Heya. I'm here with you today on Vs Battles Wiki to inform you that we... Don't exactly have anything regarding explosions against trees. So, I came across this: https://vsbattles.fandom.com/wiki/User_blog:TheShape03/Konosuba:_Megumin's_Explosion_in_Volume_4
So the calc used here originally made use of the overpressure value used to destroy wooden structures because the feat involved destroying, well... Trees. No cabins, just straight up trees.
Now, not to throw anyone under the bus here, but even in engineering property listings for various woods, trees are treated differently from planks of wood (hence why trees are listed as "green," meanwhile boards of wood are listed as "12% moisture content."). By this logic, it is also natural to assume trees react differently to explosions.
Now right off the bat, a tree with a 12-inch trunk is going to be harder to break than a wooden door or window. They are thicker after all. At the same time, however, explosions tend to blanket-demolish anything they touch. I looked into it and came across a military document on the matter: https://apps.dtic.mil/sti/pdfs/AD0801308.pdf
So that being said, the abstract says the following:
"The lower limit of peak dynamic pressure for complete breakage of isolated conifers is estimated to be in the order of 0.7 psi when associated with 1-sec positive phase duration. This value of dynamic pressure corresponds to a sea level overpressure of 5.5 psi for Mach reflection."
Section 2.1 claims that a tree with a trunk diameter of 24 inches would be expected to break at 7.5 psi. This is the highest value listed anywhere on the document.
Calculations made on trees with trunk diameters ranging from 8 to 24 inches are plotted on Figure 2.1 estimate overpressure values ranging from 2 to 5.5 psi. Solely focusing on the median value of 16 inches in diameter, these overpressure values range from 3 to 4 psi.
As for the experiment itself, the experiment used 16 trees with trunk diameters ranging from 7.5 to 10.8 inches. Said trees were tested against explosives. Despite the fact that the trees are on the thinner end of the scale, the overpressure values that broke the trees range from 3.6 to 5.3 psi, as shown in Table 4.2.
So where would that leave us? Personally, I imagine that the hardest part would be figuring out where to put the thing on the table. Preliminary analyses sets an upper limit at 7.5 psi. That's pretty much automatic. Generally, experiments are better showings of data than calculations, yet abstracts often include what the tests ended up with. Given how the experiments showed higher results than the calculations made on those very thin trees, I feel the preliminary analyses may have more credence than what calculations suggest
Obviously no uprooting is done at any point in the experiment, which... Well, duh. Trees are pretty firmly rooted into the ground; I don't expect explosions to uproot trees any time soon. Feel free to show me a study saying otherwise.
So yeah, we have the means to add in overpressure values for destroying straight-up trees; we just gotta figure out what to do with it.
So the calc used here originally made use of the overpressure value used to destroy wooden structures because the feat involved destroying, well... Trees. No cabins, just straight up trees.
Now, not to throw anyone under the bus here, but even in engineering property listings for various woods, trees are treated differently from planks of wood (hence why trees are listed as "green," meanwhile boards of wood are listed as "12% moisture content."). By this logic, it is also natural to assume trees react differently to explosions.
Now right off the bat, a tree with a 12-inch trunk is going to be harder to break than a wooden door or window. They are thicker after all. At the same time, however, explosions tend to blanket-demolish anything they touch. I looked into it and came across a military document on the matter: https://apps.dtic.mil/sti/pdfs/AD0801308.pdf
So that being said, the abstract says the following:
"The lower limit of peak dynamic pressure for complete breakage of isolated conifers is estimated to be in the order of 0.7 psi when associated with 1-sec positive phase duration. This value of dynamic pressure corresponds to a sea level overpressure of 5.5 psi for Mach reflection."
Section 2.1 claims that a tree with a trunk diameter of 24 inches would be expected to break at 7.5 psi. This is the highest value listed anywhere on the document.
Calculations made on trees with trunk diameters ranging from 8 to 24 inches are plotted on Figure 2.1 estimate overpressure values ranging from 2 to 5.5 psi. Solely focusing on the median value of 16 inches in diameter, these overpressure values range from 3 to 4 psi.
As for the experiment itself, the experiment used 16 trees with trunk diameters ranging from 7.5 to 10.8 inches. Said trees were tested against explosives. Despite the fact that the trees are on the thinner end of the scale, the overpressure values that broke the trees range from 3.6 to 5.3 psi, as shown in Table 4.2.
So where would that leave us? Personally, I imagine that the hardest part would be figuring out where to put the thing on the table. Preliminary analyses sets an upper limit at 7.5 psi. That's pretty much automatic. Generally, experiments are better showings of data than calculations, yet abstracts often include what the tests ended up with. Given how the experiments showed higher results than the calculations made on those very thin trees, I feel the preliminary analyses may have more credence than what calculations suggest
Obviously no uprooting is done at any point in the experiment, which... Well, duh. Trees are pretty firmly rooted into the ground; I don't expect explosions to uproot trees any time soon. Feel free to show me a study saying otherwise.
So yeah, we have the means to add in overpressure values for destroying straight-up trees; we just gotta figure out what to do with it.
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