Hi, other time.
Perhaps I didn´t explain very well my question.
The problem is that x,y,z are the global coordinates of each node or element center generated.
My question was for example, if I apply a load over a surface I have two possibilities:
1.- When I do my conditions archive the load is transfered over his nodes
2.- The load is transfered over his elemens
In both cases, the final load is constant in the nodes or in the centre of the element.
An example can be a load with triangle form varing with y-varible and applied over a vertical face of a cube.
The mesh could be solid and have for example 5x5x5 elements solid.
How can I do my condition for the nodes collect the effect of the load?
I would like the new loads in the nodes would be equivalent to the original load.
Thank you, very much.
----- Original Message -----
From: Enrique Escolano
To: gidlist at gatxan.cimne.upc.es
Sent: Thursday, May 29, 2003 10:19 AM
Subject: Re: [GiDlist] Question about loads
I don't understand well your question.
If you use a condition with a autocalculated #FUNC# field, you can use for this field a equation using the variables x,y,z and other field values.
This x,y,z are the global coordinates of each node or element center generated from the geometric entity (not the line or surface local parameter coordinates).
What you want exactly to write as input for COSMOS?
Enrique Escolano
----- Original Message -----
From: Jesús Mª García
To: GID list ; gidlist at gatxan.cimne.upc.es
Sent: Wednesday, May 28, 2003 5:51 PM
Subject: [GiDlist] Question about loads
Hi everybody, I have got a question about loads:
when I apply a load over a point, this load is constant in this point and then it will be transferred over a node, that´s right.
But if I want to aply a load non constant over a line or over a surface, for example a load which it depends on the x-variable along of the entity, this means the x-coordinate will be the x-coordinate of the node or the x-coordinate of the center of the element but not the x-coordinate along the line or surface. This is different to my idea because at the end the load is constant in that point and I don´t want that.
The problem is that I´m doing a problem type for Cosmos in 3D with solid elements and Cosmos don´t admit loads non constants, so I have to give them from GiD.
Could you tell me how I can create this condition?
Thank you, very much.
I wait your answers.
Jesús Mª García Prieto
jesgarpri at terra.es
E.T.S.I.I. of Valladolid (Spain)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030601/dd94fe1e/attachment.htm
[GiDlist] Question about loads
Moderator: GiD Team
-
Pablo Perez del Castillo
[GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
-
Enrique Escolano
[GiDlist] Question about loads
You can define for example, a pressure linear with the z coordinate: P(z)=Density*(Zref-z)
NUMBER: 1 CONDITION: Hydrostatic-Load
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
QUESTION: Z_Reference:
VALUE: 0
QUESTION: Density:
VALUE: 1.0
QUESTION: Pressure#FUNC#(Cond(2,REAL)*(Cond(1,REAL)-z)
VALUE: Autocalculated
STATE:hidden
END CONDITION
The Pressure field obtained foreach node is not constant, it's the result of evaluate the function (using for each node your z coordinate)
Enrique Escolano
----- Original Message -----
From: Jesús Mª García
To: gidlist at gatxan.cimne.upc.es
Sent: Sunday, June 01, 2003 4:53 PM
Subject: Re: [GiDlist] Question about loads
Hi, other time.
Perhaps I didn´t explain very well my question.
The problem is that x,y,z are the global coordinates of each node or element center generated.
My question was for example, if I apply a load over a surface I have two possibilities:
1.- When I do my conditions archive the load is transfered over his nodes
2.- The load is transfered over his elemens
In both cases, the final load is constant in the nodes or in the centre of the element.
An example can be a load with triangle form varing with y-varible and applied over a vertical face of a cube.
The mesh could be solid and have for example 5x5x5 elements solid.
How can I do my condition for the nodes collect the effect of the load?
I would like the new loads in the nodes would be equivalent to the original load.
Thank you, very much.
----- Original Message -----
From: Enrique Escolano
To: gidlist at gatxan.cimne.upc.es
Sent: Thursday, May 29, 2003 10:19 AM
Subject: Re: [GiDlist] Question about loads
I don't understand well your question.
If you use a condition with a autocalculated #FUNC# field, you can use for this field a equation using the variables x,y,z and other field values.
This x,y,z are the global coordinates of each node or element center generated from the geometric entity (not the line or surface local parameter coordinates).
What you want exactly to write as input for COSMOS?
Enrique Escolano
----- Original Message -----
From: Jesús Mª García
To: GID list ; gidlist at gatxan.cimne.upc.es
Sent: Wednesday, May 28, 2003 5:51 PM
Subject: [GiDlist] Question about loads
Hi everybody, I have got a question about loads:
when I apply a load over a point, this load is constant in this point and then it will be transferred over a node, that´s right.
But if I want to aply a load non constant over a line or over a surface, for example a load which it depends on the x-variable along of the entity, this means the x-coordinate will be the x-coordinate of the node or the x-coordinate of the center of the element but not the x-coordinate along the line or surface. This is different to my idea because at the end the load is constant in that point and I don´t want that.
The problem is that I´m doing a problem type for Cosmos in 3D with solid elements and Cosmos don´t admit loads non constants, so I have to give them from GiD.
Could you tell me how I can create this condition?
Thank you, very much.
I wait your answers.
Jesús Mª García Prieto
jesgarpri at terra.es
E.T.S.I.I. of Valladolid (Spain)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030602/364331e5/attachment.htm
NUMBER: 1 CONDITION: Hydrostatic-Load
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
QUESTION: Z_Reference:
VALUE: 0
QUESTION: Density:
VALUE: 1.0
QUESTION: Pressure#FUNC#(Cond(2,REAL)*(Cond(1,REAL)-z)
VALUE: Autocalculated
STATE:hidden
END CONDITION
The Pressure field obtained foreach node is not constant, it's the result of evaluate the function (using for each node your z coordinate)
Enrique Escolano
----- Original Message -----
From: Jesús Mª García
To: gidlist at gatxan.cimne.upc.es
Sent: Sunday, June 01, 2003 4:53 PM
Subject: Re: [GiDlist] Question about loads
Hi, other time.
Perhaps I didn´t explain very well my question.
The problem is that x,y,z are the global coordinates of each node or element center generated.
My question was for example, if I apply a load over a surface I have two possibilities:
1.- When I do my conditions archive the load is transfered over his nodes
2.- The load is transfered over his elemens
In both cases, the final load is constant in the nodes or in the centre of the element.
An example can be a load with triangle form varing with y-varible and applied over a vertical face of a cube.
The mesh could be solid and have for example 5x5x5 elements solid.
How can I do my condition for the nodes collect the effect of the load?
I would like the new loads in the nodes would be equivalent to the original load.
Thank you, very much.
----- Original Message -----
From: Enrique Escolano
To: gidlist at gatxan.cimne.upc.es
Sent: Thursday, May 29, 2003 10:19 AM
Subject: Re: [GiDlist] Question about loads
I don't understand well your question.
If you use a condition with a autocalculated #FUNC# field, you can use for this field a equation using the variables x,y,z and other field values.
This x,y,z are the global coordinates of each node or element center generated from the geometric entity (not the line or surface local parameter coordinates).
What you want exactly to write as input for COSMOS?
Enrique Escolano
----- Original Message -----
From: Jesús Mª García
To: GID list ; gidlist at gatxan.cimne.upc.es
Sent: Wednesday, May 28, 2003 5:51 PM
Subject: [GiDlist] Question about loads
Hi everybody, I have got a question about loads:
when I apply a load over a point, this load is constant in this point and then it will be transferred over a node, that´s right.
But if I want to aply a load non constant over a line or over a surface, for example a load which it depends on the x-variable along of the entity, this means the x-coordinate will be the x-coordinate of the node or the x-coordinate of the center of the element but not the x-coordinate along the line or surface. This is different to my idea because at the end the load is constant in that point and I don´t want that.
The problem is that I´m doing a problem type for Cosmos in 3D with solid elements and Cosmos don´t admit loads non constants, so I have to give them from GiD.
Could you tell me how I can create this condition?
Thank you, very much.
I wait your answers.
Jesús Mª García Prieto
jesgarpri at terra.es
E.T.S.I.I. of Valladolid (Spain)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030602/364331e5/attachment.htm
-
Jesús Mª García
[GiDlist] Question about loads
Hello:
other problem on relation on the before problem, with this condition or with
other similar when you apply a load, the final load depends on the number of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic load
and my cube is meshed with 2x2x2 elements, the nodes on top have the value
of the load, the nodes in the middle of the surface have half value of the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5 F
In other case if my cube is meshed with 4x4x4 elements, the total load is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the total
load would be the same in both cases and it wouldn´t depend on the number of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
other problem on relation on the before problem, with this condition or with
other similar when you apply a load, the final load depends on the number of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic load
and my cube is meshed with 2x2x2 elements, the nodes on top have the value
of the load, the nodes in the middle of the surface have half value of the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5 F
In other case if my cube is meshed with 4x4x4 elements, the total load is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the total
load would be the same in both cases and it wouldn´t depend on the number of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
-
Enrique Escolano
[GiDlist] Question about loads
In fact, is a bad design to define a concentrated force over lines, surfaces
or volumes to be transferred over nodes.
The correct design is to apply a pressure to be transfered over a element
face, then the total force not dependent of the mesh size.
But if your code cannot support pressures, and you must set the total force
to a user value=A, must calculate a new
weighted value for each node. For example compute the forces summatory
Sum(Fi), and write for each node i the value Fi/Sum(Fi)*A
Note: can make some small operation inside the bas file, using the
*operation command
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 5:59 PM
Subject: Re: [GiDlist] Question about loads
Hello:
other problem on relation on the before problem, with this condition or
with
other similar when you apply a load, the final load depends on the number
of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic load
and my cube is meshed with 2x2x2 elements, the nodes on top have the value
of the load, the nodes in the middle of the surface have half value of the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5 F
In other case if my cube is meshed with 4x4x4 elements, the total load
is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the
total
load would be the same in both cases and it wouldn´t depend on the number
of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
or volumes to be transferred over nodes.
The correct design is to apply a pressure to be transfered over a element
face, then the total force not dependent of the mesh size.
But if your code cannot support pressures, and you must set the total force
to a user value=A, must calculate a new
weighted value for each node. For example compute the forces summatory
Sum(Fi), and write for each node i the value Fi/Sum(Fi)*A
Note: can make some small operation inside the bas file, using the
*operation command
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 5:59 PM
Subject: Re: [GiDlist] Question about loads
Hello:
other problem on relation on the before problem, with this condition or
with
other similar when you apply a load, the final load depends on the number
of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic load
and my cube is meshed with 2x2x2 elements, the nodes on top have the value
of the load, the nodes in the middle of the surface have half value of the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5 F
In other case if my cube is meshed with 4x4x4 elements, the total load
is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the
total
load would be the same in both cases and it wouldn´t depend on the number
of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
-
Jesús Mª García
[GiDlist] Question about loads
It´s a good idea but I see a problem:
if I do that the total force is the same in both cases but the resultant
moment is different.
That is my main problem because I don´t know to do a system of forces
equivalent to my original load.
While the force is equivalent the moment isn´t.
Cosmos support pressures but the pressures are constant in each element.
I have a question, when I apply a load over a element face, if that load
isn´t constant, does Gid know to put in each node his exact force to do the
system equivalent?
I send you a draw to explain the situation.
Thank you other time.
Jesús García Prieto
Valladolid (Spain)
----- Original Message -----
From: "Enrique Escolano" escolano at cimne.upc.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 8:50 PM
Subject: Re: [GiDlist] Question about loads
In fact, is a bad design to define a concentrated force over lines,
surfaces
or volumes to be transferred over nodes.
The correct design is to apply a pressure to be transfered over a element
face, then the total force not dependent of the mesh size.
But if your code cannot support pressures, and you must set the total
force
to a user value=A, must calculate a new
weighted value for each node. For example compute the forces summatory
Sum(Fi), and write for each node i the value Fi/Sum(Fi)*A
Note: can make some small operation inside the bas file, using the
*operation command
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 5:59 PM
Subject: Re: [GiDlist] Question about loads
Hello:
other problem on relation on the before problem, with this condition or
with
other similar when you apply a load, the final load depends on the
number
of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic
load
and my cube is meshed with 2x2x2 elements, the nodes on top have the
value
of the load, the nodes in the middle of the surface have half value of
the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5
F
In other case if my cube is meshed with 4x4x4 elements, the total load
is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the
total
load would be the same in both cases and it wouldn´t depend on the
number
of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Loads.JPG
Type: image/jpeg
Size: 10561 bytes
Desc: not available
Url : http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030605/d7080bcc/attachment.jpeg
if I do that the total force is the same in both cases but the resultant
moment is different.
That is my main problem because I don´t know to do a system of forces
equivalent to my original load.
While the force is equivalent the moment isn´t.
Cosmos support pressures but the pressures are constant in each element.
I have a question, when I apply a load over a element face, if that load
isn´t constant, does Gid know to put in each node his exact force to do the
system equivalent?
I send you a draw to explain the situation.
Thank you other time.
Jesús García Prieto
Valladolid (Spain)
----- Original Message -----
From: "Enrique Escolano" escolano at cimne.upc.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 8:50 PM
Subject: Re: [GiDlist] Question about loads
In fact, is a bad design to define a concentrated force over lines,
surfaces
or volumes to be transferred over nodes.
The correct design is to apply a pressure to be transfered over a element
face, then the total force not dependent of the mesh size.
But if your code cannot support pressures, and you must set the total
force
to a user value=A, must calculate a new
weighted value for each node. For example compute the forces summatory
Sum(Fi), and write for each node i the value Fi/Sum(Fi)*A
Note: can make some small operation inside the bas file, using the
*operation command
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 5:59 PM
Subject: Re: [GiDlist] Question about loads
Hello:
other problem on relation on the before problem, with this condition or
with
other similar when you apply a load, the final load depends on the
number
of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic
load
and my cube is meshed with 2x2x2 elements, the nodes on top have the
value
of the load, the nodes in the middle of the surface have half value of
the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5
F
In other case if my cube is meshed with 4x4x4 elements, the total load
is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the
total
load would be the same in both cases and it wouldn´t depend on the
number
of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Loads.JPG
Type: image/jpeg
Size: 10561 bytes
Desc: not available
Url : http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030605/d7080bcc/attachment.jpeg
-
Enrique Escolano
[GiDlist] Question about loads
GiD is a neutral program, and it unknow if your condition is a force, a pressure, a velocity, a label, etc.
It cannot translate automatically from geometry to nodes the "unknown field" with a "equivalent system"
as desired in this particular case (from pressure to puntual loads).
It is needed to write this specific translation inside the bas file, or with and auxiliar code that read the input
file, and rewrite it modified.
You can convert the continuous load over a element to some equivalent (F=Sum Fi, and M=Sum Mi ) forces over the nodes, for example:
You assign in GiD with a #FUNC# field condition the Pa,Pb values, and after process the calculation file (with a external code, or tcl if needed)
to calculate the accumulated Fa,Fb
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Thursday, June 05, 2003 10:58 PM
Subject: Re: [GiDlist] Question about loads
It´s a good idea but I see a problem:
if I do that the total force is the same in both cases but the resultant
moment is different.
That is my main problem because I don´t know to do a system of forces
equivalent to my original load.
While the force is equivalent the moment isn´t.
Cosmos support pressures but the pressures are constant in each element.
I have a question, when I apply a load over a element face, if that load
isn´t constant, does Gid know to put in each node his exact force to do the
system equivalent?
I send you a draw to explain the situation.
Thank you other time.
Jesús García Prieto
Valladolid (Spain)
----- Original Message -----
From: "Enrique Escolano" escolano at cimne.upc.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 8:50 PM
Subject: Re: [GiDlist] Question about loads
In fact, is a bad design to define a concentrated force over lines,
surfaces
or volumes to be transferred over nodes.
The correct design is to apply a pressure to be transfered over a element
face, then the total force not dependent of the mesh size.
But if your code cannot support pressures, and you must set the total
force
to a user value=A, must calculate a new
weighted value for each node. For example compute the forces summatory
Sum(Fi), and write for each node i the value Fi/Sum(Fi)*A
Note: can make some small operation inside the bas file, using the
*operation command
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 5:59 PM
Subject: Re: [GiDlist] Question about loads
Hello:
other problem on relation on the before problem, with this condition or
with
other similar when you apply a load, the final load depends on the
number
of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic
load
and my cube is meshed with 2x2x2 elements, the nodes on top have the
value
of the load, the nodes in the middle of the surface have half value of
the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5
F
In other case if my cube is meshed with 4x4x4 elements, the total load
is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the
total
load would be the same in both cases and it wouldn´t depend on the
number
of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030606/cfbd1a2c/attachment.htm
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/bmp
Size: 350262 bytes
Desc: not available
Url : http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030606/cfbd1a2c/attachment.bin
It cannot translate automatically from geometry to nodes the "unknown field" with a "equivalent system"
as desired in this particular case (from pressure to puntual loads).
It is needed to write this specific translation inside the bas file, or with and auxiliar code that read the input
file, and rewrite it modified.
You can convert the continuous load over a element to some equivalent (F=Sum Fi, and M=Sum Mi ) forces over the nodes, for example:
You assign in GiD with a #FUNC# field condition the Pa,Pb values, and after process the calculation file (with a external code, or tcl if needed)
to calculate the accumulated Fa,Fb
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Thursday, June 05, 2003 10:58 PM
Subject: Re: [GiDlist] Question about loads
It´s a good idea but I see a problem:
if I do that the total force is the same in both cases but the resultant
moment is different.
That is my main problem because I don´t know to do a system of forces
equivalent to my original load.
While the force is equivalent the moment isn´t.
Cosmos support pressures but the pressures are constant in each element.
I have a question, when I apply a load over a element face, if that load
isn´t constant, does Gid know to put in each node his exact force to do the
system equivalent?
I send you a draw to explain the situation.
Thank you other time.
Jesús García Prieto
Valladolid (Spain)
----- Original Message -----
From: "Enrique Escolano" escolano at cimne.upc.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 8:50 PM
Subject: Re: [GiDlist] Question about loads
In fact, is a bad design to define a concentrated force over lines,
surfaces
or volumes to be transferred over nodes.
The correct design is to apply a pressure to be transfered over a element
face, then the total force not dependent of the mesh size.
But if your code cannot support pressures, and you must set the total
force
to a user value=A, must calculate a new
weighted value for each node. For example compute the forces summatory
Sum(Fi), and write for each node i the value Fi/Sum(Fi)*A
Note: can make some small operation inside the bas file, using the
*operation command
Enrique Escolano
----- Original Message -----
From: "Jesús Mª García" jesgarpri at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Tuesday, June 03, 2003 5:59 PM
Subject: Re: [GiDlist] Question about loads
Hello:
other problem on relation on the before problem, with this condition or
with
other similar when you apply a load, the final load depends on the
number
of
the nodes.
For example, I have other time a cube.
If I apply a triangle load over a lateral surface like a hydrostatic
load
and my cube is meshed with 2x2x2 elements, the nodes on top have the
value
of the load, the nodes in the middle of the surface have half value of
the
load and the nodes down haven´t load.
I can add the differents values: Total Load = 3 * F + 3 * 0.5 * F = 4.5
F
In other case if my cube is meshed with 4x4x4 elements, the total load
is:
Total Load = 5 * F + 5 * 0.75 * F + 5 * 0.5 * F + 5 * 0.25 * F = 12.5 F
So my question is, are there any way to do this? I would like that the
total
load would be the same in both cases and it wouldn´t depend on the
number
of
nodes in the surface.
So the total load would be independent of the nodes´ number.
Thank you, I believe that isn´t easy to do that.
Jesús.
----- Original Message -----
From: "Pablo Perez del Castillo" pablopdc at terra.es
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, June 02, 2003 10:27 AM
Subject: Re: [GiDlist] Question about loads
Hello;
You have examples in the GIDLIST over this question;
Try this:
File: *.cnd
NUMBER: 1 CONDITION: Hydrostatic_pressure
CONDTYPE: over surfaces
CONDMESHTYPE: over nodes
CANREPEAT: yes
QUESTION: Density:
VALUE: 0
QUESTION: Z_Water_Level:
VALUE: 0
QUESTION: AutoCalculatePressure#FUNC#(Cond(1,REAL)*(Cond(2,REAL)-z))
VALUE: AutoCalculate
END CONDITION
file:*.bas
*Set Cond Hydrostatic_pressure *nodes
*loop nodes *OnlyInCond
*nodesnum *Cond(AutoCalculatePressure)
*end nodes
Pablo
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
_______________________________________________
GiDlist mailing list
GiDlist at gid.cimne.upc.es
http://gid.cimne.upc.es/mailman/listinfo/gidlist
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030606/cfbd1a2c/attachment.htm
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/bmp
Size: 350262 bytes
Desc: not available
Url : http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20030606/cfbd1a2c/attachment.bin