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Lift of alpine skis.

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I am completely new to Comsol Multiphysics but I need it for my master thesis.
I have the following problem:
- Simulation of the lift of alpine skiers, which are loaded with certain mass in powder conditions.

For me, there are various problems:
- The lift of snow is different to lift in the air. A ski doesn't get it's lift like an airplane, the ski gets it's lift because of the speed of the skier. The longer the air needs" to get out of the snow" under the ski, the more lift the skier get.
--> but, how is it possible to do something like this?

Any ideas?
Best Regards,
Felix

4 Replies Last Post 4 sept. 2012, 07:55 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 7 mai 2012, 14:15 UTC−4
Hi

interesting problem,
should you approach it via CFD or non linear materials ?
new features are annonced in 4.3 for next month I have heard ? ;)

How do you express your material (snow) properties, depending on the pressure and the velocity of the ski, and should you consider snow as a fluid, or non-linear solid, or a 2 component fluid (air+snow) ... or ?

better to get some feeling of how to do this (how its done by other snow experts i.e avalanche experts, car tire experts ... ?) before starting to simulate

--
Good luck
Ivar
Hi interesting problem, should you approach it via CFD or non linear materials ? new features are annonced in 4.3 for next month I have heard ? ;) How do you express your material (snow) properties, depending on the pressure and the velocity of the ski, and should you consider snow as a fluid, or non-linear solid, or a 2 component fluid (air+snow) ... or ? better to get some feeling of how to do this (how its done by other snow experts i.e avalanche experts, car tire experts ... ?) before starting to simulate -- Good luck Ivar

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Posted: 1 decade ago 8 mai 2012, 06:17 UTC−4
I don't know if i should use "CFD" or "non-linear materials", I have not any approaches by my lectors. I would like to choose the easiest one ;-). What do you think is the best?
Maybe I can implement some differential equation of "lift"? I am already looking for one of these equations.

I think as material an 2-component fluid (snow&air) should be expressed, I think this would fit perfect for my problem.
Do you know any experts who have experiences with "Snow"? Or any good papers?
Best regards,
Felix
I don't know if i should use "CFD" or "non-linear materials", I have not any approaches by my lectors. I would like to choose the easiest one ;-). What do you think is the best? Maybe I can implement some differential equation of "lift"? I am already looking for one of these equations. I think as material an 2-component fluid (snow&air) should be expressed, I think this would fit perfect for my problem. Do you know any experts who have experiences with "Snow"? Or any good papers? Best regards, Felix

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 8 mai 2012, 08:05 UTC−4
Hi

start by some litterature survey, you can certainly build your own PDEs with COMSOL, but it's quicker to start with an existing physics module. I think it's only in CFD that you have 2 fluid options (to be checked with comsol support) and the new trend of non linear material physics simulations are to come in next release in a months time, but there are many things that can be done already today

--
Good luck
Ivar
Hi start by some litterature survey, you can certainly build your own PDEs with COMSOL, but it's quicker to start with an existing physics module. I think it's only in CFD that you have 2 fluid options (to be checked with comsol support) and the new trend of non linear material physics simulations are to come in next release in a months time, but there are many things that can be done already today -- Good luck Ivar

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Posted: 1 decade ago 4 sept. 2012, 07:55 UTC−4
Hi,
Now I already have comsol experiences for some months. I managed to do my simulation quite well, but with one still existing problem. I already used mediums like air and water for my lift simulations, but I don't know how to define snow.
I think I have to use a particle system, can somebody help me with this problem?
Would be great,
Best Regards,
Felix
Hi, Now I already have comsol experiences for some months. I managed to do my simulation quite well, but with one still existing problem. I already used mediums like air and water for my lift simulations, but I don't know how to define snow. I think I have to use a particle system, can somebody help me with this problem? Would be great, Best Regards, Felix

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