Lateral Diffusion within Plume

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Lateral Diffusion within Plume

Post by kjmohr »


I have been running a coupled HySPLIT model with a volcanic plume model and our volcanic depositions are extremely narrow, to where it does not seem there is really any lateral diffusion within the plume. I was wondering if there is a way to change the lateral diffusion within the plume? I see there is a horizontal turbulence parameter, would that be the most similar thing to changing the lateral diffusion (as in, make the deposit more broad and less narrow)?

Thank you,

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Joined: February 8th, 2016, 12:56 pm
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Re: Lateral Diffusion within Plume

Post by alicec »

Often the turbulent mixing in volcanic plume simulations is quite low as the mixing decreases with height.
To increase mixing you can try several things.

Use kzmix and tvmix to increase the mixing coefficients.

Try using kdef=1 to compute horizontal turbulence from velocity deformation.

If you are using a vertical line source for your eruption, you may also want to try using a wider source term.
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