Navier-Stokes Lava Problem

General discussion about Elmer
Post Reply
awesomealzo
Posts: 1
Joined: 14 Aug 2020, 18:55
Antispam: Yes

Navier-Stokes Lava Problem

Post by awesomealzo »

Hi there hope someone can help.

I am doing a project for university where I have a flow of andesitic lava 10m thick. Part of the problem requires me to calculate the velocity of convection within the flow. I struggled to get to grips solving this and discovered ELMER as a tool to help me calculate this. I am unfamiliar with the functions in ELMER but I know I need to use Navier-Stokes equations. I have created a 10 by 10 by 10 cube mesh. My research question has limited parameters, so I have assumed the base as solid ground, the top and 2 sides are air, and the front and back are the beginning (inlet) and end (outlet) of the lava flow. The andesitic lava has a flow velocity ranging between 10 and 50 m3/s, & maximum temperature is 1200'C.

I would really appreciate some guidance!
mzenker
Posts: 1999
Joined: 07 Dec 2009, 11:49
Location: Germany

Re: Navier-Stokes Lava Problem

Post by mzenker »

Hi,

did you have a look on glacier simulation with Elmer/Ice? I don't have any experience with it myself, and I don't know to which extent they are comparable, but at least in both cases you have a thick fluid flowing over ground...

HTH,
Matthias
raback
Site Admin
Posts: 4812
Joined: 22 Aug 2009, 11:57
Antispam: Yes
Location: Espoo, Finland
Contact:

Re: Navier-Stokes Lava Problem

Post by raback »

Hi

Probably this case indeed bears significant similarity to Elmer/Ice stuff. I would think that you cannot neglect inertia but neither do you probably have turbulence. As for Ice the Lava probably has some nonlinear viscosity models. If you intend to do 10x10x10 then I would think that you're looking for periodic BCs. I suggest that you start then from test cases "NonnewtonianChannelFlow*".

I guess a challenge is that even though the velocity could be periodic the temperature might not be it since the lava is gradually cooling. If you don't assume cooling it would be isothermal.

To go forward you need to figure out your material parameters & boundary conditions. Also, what specifically is the research problem you're trying to answer?

-Peter
Post Reply