What is a particle and a drifters equivalent?

EFDC_Explorer
1

I try to simulate an oil spill, a spill of approximately 1000 barrels of oil, I do not understand how I can enter this value. What does a "particle" mean?
I honestly do not understand or translate the term "drifters", what is this?

Thank you very much for the help,

Nury

2

Hi Nury, EE uses Lagrangian particle tracking module to simulate the oil spill. You can specify the oil parameters within EE where you can enter the volume of oil for the group of particles, biodegradation rate, vapor pressur etc. The main Lagrangian Particle Tracking form looks like following:

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In tab "Seeding Utility: By Group", you can create a new group. In the above figure I have created a group called "Group1". Then you can click on the Use checkbox below Oil Spill Options. After the checkbox is checked, click on properties button to specify your oil spill parameters. The form is as follows: This is how you specify oil parameters. For details on specifying oil spill with EE please follow this link to knowledge base: https://eemodelingsystem.atlassian.net/wiki/display/EEREF/Oil+Spill+Modeling+with+Lagrangian+Particle+Tracking Best, Janesh Devkota

3

I try to simulate an oil spill, a spill of approximately 1000 barrels of oil, I do not understand how I can enter this value. What does a “particle” mean? I honestly do not understand or translate the term “drifters”, what is this? Thank you very much for the help, Nury Attached files

4

A drifter is simply another name for a particle. When you define a number of particles they are part of a "group." This is what this image you sent is asking, how many particles will be created, or seeded, in this group. The oil spill module in EE lets you decide the volume of oil that is associated with that group of particles. You can then create another group with a different number of particles with a different volume of oil if you want to.

5

Hello all, thank you very much for the constant answers. Actually, the only thing I do not understand about the particles is the following: what is the basis for deciding how many particles to create? I mean, if I want to simulate a 150 m3 or 75 m3 spill, what does it say How many particles should I create?

really thank you very much

6

Hello everyone! you have not answered me … but it does not matter I have been overcoming the errors that come out … there is something that generates a lot of restlessness, when I decrease the flow and speeds of the system (I am simulating a river), I see that after a Time the oil slick simply disappears … I take into account the following "It should be noted that EFDC will cause the drifter to disappear when the oil per drifter is less than 1.0 mm3." … but I do not know if it is happening in me Case … what does it mean? It biodegrades?

thank you very much

7

It may be that your degradation rate is too high leading to rapid biodegradation of the oil. Also, the oil will naturally evaporate over time depending on how you have set your vapor pressure. In order to simulate a conservative oil, you would set the degradation rate and the vapor pressure as zero. https://eemodelingsystem.atlassian.net/wiki/display/EEREF/Oil+Spill+Modeling+with+Lagrangian+Particle+Tracking