What is the difference between bonding and additive bodies in ANSYS

Bonding is generally very close to each other, used for bodies with a certain gap, and can also be used for addition operations, at this time, the effect of the two is the same;

The two bodies after bonding are still two bodies, and the number of bodies does not change;

Two bodies with overlapping parts are generally not bonded, but are directly added, and after addition, they become one body.

Bonding is at the borders of contact, which when added together become a whole.

The result of the addition operation is to obtain a new figure containing all parts of each original figure, note that it is a new figure, so that the new figure formed is a single whole with no gaps. In ANSYS, you can only work with 3D solids or 2D coplanar faces.

The bonding operation is performed only on the common parts between the shapes, and the dimensions of the common parts are lower than the original one-dimensional. That is to say, the common part of the face and the surface bonding can only be lines, and the body and body can only be faces. And the faces and faces or the bodies are only connected on the boundary, note that they are only connected on the boundary, but they are still independent of each other.

For example, if two cubes are in contact with each other, enter vlist, you will find that there are 12 faces in the window, if you glue the two cubes and enter vlist, there are only 11 faces in the window, then you will see that the two bodies will have a common face (see the number number). Bodies or surfaces with overlapping parts are generally not bonded to each other. You get the idea?

Taking two adjacent faces as an example, compositing is the merging of two faces into a single face; After bonding, there are still two sides; The cm command has no effect on the geometry, it just defines some names for the geometry and makes it easier to manipulate later.

Bonding operations are Boolean operations;

Node coupling, on the other hand, is a boundary process, not a matter of using one layer.

1. The bonding command is used in the processing process of the geometric model, and can only be used where the model has a common surface, and in the process of dividing and playing with the mesh for calculation, the bonding of the common surface is equivalent to all the degrees of freedom coupling of all nodes on this surface;

2. Node coupling is used in the finite element model, that is, on the model that has been divided into meshes, and the scope of node coupling is relatively wide, it can be any number of nodes or a set of nodes, there is no requirement for coplanarity, and there is no requirement for the number of degrees of freedom, and a single degree of freedom of multiple nodes can be coupled, or it can be a plurality of degrees of freedom, according to the specific situation.

After bonding, the difference between the original solid (e.g., different materials) can be maintained

There must be a difference between this, as far as my personal practice and understanding, the difference between add, overlap and glue under Boolean operations should be like this:

add is to merge two elements with a common part into a new element, no longer retaining the boundaries of the common part.

overlap is to turn an object with overlapping parts into several consecutive objects, that is, the overlapping part becomes an object that is contiguous with other parts;

The glue operation is to connect two or more primitives together, using a common boundary, and this kind of problem that is still electrically professional should be a bit of a bounty, otherwise who will give you a bunch of them.

After doing the glue or add operation, you can understand that the two bodies are integrated into one. When calculating, it is deformed according to one volume.

Are you talking about lapping to consider the contact between two objects? If so, it is still two bodies, and the deformation of the two bodies is calculated separately.

It is recommended that you make an example of a double-layer stacked beam deformation. Both beams are 20x5, one up and down, one end of the beam is fixed and the other end is free. One of them, one of the models glued two beams; The other model makes contact between the two beams. Add the same load to the free end and look at the stress diagram.

The results are clear.

We've done simulations on this, can we help you do that? Contact?

overlap — an overlapping operation. A collection of three or more new drawings that are used to connect two or more drawings. Overlapping operations generate multiple relatively simple regions, while addition operations produce a relatively complex region.

The overlapping area must have the same dimension as the original drawing.

Note: Addition is the addition of multiple graphs to form a whole. After the addition operation, there is only one entity left in the end. After the overlapping operation, the number of solids remains the same, but the gaps between the entities are eliminated (the existence of gaps will directly lead to the failure of the finite element calculation).

Glue – Bonding Operations. Bonding operations are similar to overlapping operations, but bonding operations are performed only on the immediate common part of the graph, and the number of dimensions of the common part is lower than that of the original one-dimensional. For example:

Face-to-face bonding operations are performed for faces and their common edges. The bonding operation of the body and the body is performed for the common surface of the body and the body. These faces are connected to each other or body-to-body only on boundaries, but are still independent of each other.

Note: After the bonding operation, the bonded entities are coplanar, that is, there is a common face between the two entities.

The difference between glue and overlap has been discussed with people before, in fact, you can do this, either glue, or overlap, anyway, it is the operation of the solid model, not much difference, of course, the subtle difference you can look at the description of the command in help, the latter is to produce some new faces or volumes, and the former is to connect the surface and the body, without creating anything new, the mass element is a mass finite element, defined by mass elements such as mass, The properties are then added to a point to complete the creation of the mass cell.

*tie or *contact pair tied, or *contact pair noseperation.

A glue is the glue of two or more sibling pixels together, with a shared boundary on their contact surfaces, also known as a "merge".

The bonding operation requires that the graphes participating in the operation cannot have intersecting graphes of the same level as the parent body. For example, when the body is bonded, the intersecting part cannot be a body, but it can be a surface, a line or a key point, that is, the element level of the intersecting part is lower than that of the parent body; When face-to-face bonding, the part that intersects can only be lines or keys, and these faces must be coplanar; When a wire is bonded, the part that intersects can only be the end of the line, for example, two lines that do not intersect at the end cannot be bonded.

The bonding operation is different from the addition operation, which combines the input graph operation into one matrix, and the number of mothers participating in the operation does not change after the bonding operation, that is, the matrix does not change but the common boundary is shared. Bonding operations are very useful in meshing, i.e., each parent can have different physical and mesh properties to obtain a good mesh. It is also not the inverse of the partition operation, because the boundary between the pixels is shared after the segmentation operation, and there is no need for bonding operations.

When building a more complex model, you can create individual elements independently, and then use bonding operations to make them share boundaries. It's the same as taking a variety of methods to create a matrix and then slicing the effect. If the elements themselves share a boundary, of course, there is no need for bonding operations.

After the bonding operation is completed, the input pixels are processed using the settings in BOPTN. There are only 3 bonding commands, which are explained below:

Wire bonding: LGLUE, NL1, NL2, NL3, NL4, NL5, NL6, NL7, NL8, NL9

Surface bonding: Aglue, Na1, Na2, Na3, Na4, Na5, Na6, Na7, Na8, Na9

Body bonding: VGLUE, NV1, NV2, NV3, NV4, NV5, NV6, NV7, NV8, NV9

where NX1 NX9 is the number of the bonding element, and NX1 can be P, All, or the component name (where X represents L, A, V).