How to apply a centrifugal load on a blade geometry
I want to apply a centrifugal load to a single blade geometry but not sure how to use RFORCE card to apply that?
In the help of RFORCE following parameters need to be specified
G - origin of rota vector
CID - coordinate system of vector
R1R2R3 - components of vector
IDRF - id of element set applied this force
How to calculate and define R1 R2 and R3? can someone explain with an example?
Answers
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Hi moeen
R1, R2, R3 are rectangular components of the rotation direction vector. The vector defined will pass through point G
You can specify the direction of rotation by defining R1, R2, R3.
Have a look at this example file where the direction of rotation or Rforce is defined in the Z direction.
<?xml version="1.0" encoding="UTF-8"?>
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Altair Forum User said:
Hi moeen
R1, R2, R3 are rectangular components of the rotation direction vector. The vector defined will pass through point G
You can specify the direction of rotation by defining R1, R2, R3.
<?xml version="1.0" encoding="UTF-8"?>
Have a look at this example file where the direction of rotation or Rforce is defined in the Z direction.
<?xml version="1.0" encoding="UTF-8"?>
Thanks for the info now its clear to me but one more question. I need to define the centrifugal load of 100 rpm so i am thinking where should i insert that? under A or under RACC coz one is angular velocity and the other is angular acceleration?
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Hi moeen
In RFORCE card, you have a provision to input rotational velocity or acceleration. If you have the units of Rev/sec, then you need to input under the velocity.
If you have the unit of rev/sec2 then, you need to input under acceleration.
In your case, you can input the value under angular velocity.
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Altair Forum User said:
Hi moeen
In RFORCE card, you have a provision to input rotational velocity or acceleration. If you have the units of Rev/sec, then you need to input under the velocity.
If you have the unit of rev/sec2 then, you need to input under acceleration.
In your case, you can input the value under angular velocity.
Thanks a lot for clarification but one more clarification. What units should we use here? rev/s or rad/s???? its quite confusing for me at the moment.
In the manual it says radians below
angular velocity = →ω(radians/unittime)=2πA⋅→R
whereas in the same page it also mention that A is a Scale factor of the rotational velocity in revolutions per unit time. so here its saying revolutions.
but in one of the post the admin mentioned rev/sec. Can you please clarify this ?
https://community.altair.com/community?id=community_question&sys_id=2696047a1b2bd0908017dc61ec4bcb99
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Hi moeen
Altair Forum User said:What units should we use here? rev/s or rad/s????
You should give the input in the form of rev/sec.
The radians per second is the SI unit of angular velocity.
Here if you have the input in the form of rad/sec, then you have to convert it into rev/sec while inputting into HyperMesh.
ω = 1 rad/s, corresponds to a frequency of rotation of 60/(2π) rpm ≈ 9.55 rpm
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