Learning Forum

[issa]

how can i model a different types of soil materials in explicit dynamics , and which parameters should i fill , is it possible to use the linear-elastic ones .

[peteroznewman]

What do you want to simulate?

What velocities are involved?

Which soil material model do you want to use?

It will be much easier to advise you if you provide some more details.

[issa]

hi 

i should simulate the stress , deformation, velocity and acceleration to a blade of a power harrow on different types of soil such as sandy soil, silty soil, and clay .

the velocities involved are angular and linear together since its a rotary harrow.

 

 

[peteroznewman]

Can you provide the geometry of the blade? You can attach project archives or zip files to your posts if they are < 120 MB.

What is the dimension from the center of rotation to the surface of the soil?

[issa]

[issa]

this is done with sand which already modeled in explicit dynamics.

[peteroznewman]

I found out you are on Release 19.0.  It's better if you say that when you attach an archive because an older version can't open a newer archive.

Are you on the Student license or a Research license?

[peteroznewman]

The element size for the sand has to be as small as you want individual elements to erode (be removed from the analysis) so that a larger collection of elements can be pushed by the blades. You want as small a volume of sand as you can make around the blade without influencing the motion of the sand on the blade. The solution time for a model that rotates the blade one revolution with these small elements may be tens (or hundreds) of hours. You can get some preliminary setup accomplished with solution times in minutes if you scale up the geometry by 1000 times.

I asked about Student vs Research license because as you make the sand elements smaller, you will quickly exceed the allowable number of nodes and elements on the Student license.

[peteroznewman]

I made a version of your geometry that is 1000 times larger, but even then, I recommend you delete all the rounds (or blends) from all the edges of your rotor blade. They are creating much smaller elements that force Explicit Dynamics to take much smaller steps than is necessary. There is no point in having features on the blade smaller than the element size in the sand.

I also rearranged the rotor to plunge into the soil. Take a look at the attached archive, but please reply with geometry that has no rounds.

[issa]

Thank you for your reply i will attach the blade soon without rounds , but still my main main problem is how can i model different types of soil and using it in explicit dynamics .

thank you soo much 

[issa]

This is the blade with no rounds

[peteroznewman]

Thanks for the geometry. 

What type of license do you have: Student with limits, or Research/Commercial without node and element count limits?

The answer to that will generate a new suggestion.

[issa]

I got the research licence.

[peteroznewman]

Great, then you can pursue Explicit Dynamics. Otherwise, I was going to suggest a Fluent model.

[peteroznewman]

I  downloaded your project archive. Unfortunately, it points to the SOLIDWORKS file blade.sldprt and that is not included in the archive. Please zip blade.sldprt and attach that zip file to your reply.

 

Alternatively, open the Geometry in DesignModeler one time. The geometry will be copied into the Workbench project and should be included when you save and archive the project.