Week 6 - Creating connection for Rear door
AIM :- For the given Rear door FE model, Create and Apply different PIDs for different components. By using the same technique and the elements as shown in the video, Perform suitable connections. (No thickness need to be assigned to FE as intention is just to deploy connections).
Theory :-
1. Connections in ANSA means deployment of joints between two components at various location on a model. Joints mainly such as Steel-Steel, Wood-Steel, Glass-Steel, Glass-Wood etc. The Joints in Ansa are mainly classified as, Bolts, Welds and Adhesives.
2. In FEA, when a model has to be passed through any Type Test, The assemblies have to be connected togather so that the force acting on themodel body shoud get transmitted through different part of the body. This is where joints play a major role in ANSA. While pre processig for further analysis the connection needs to be established Among Different PIDs in ANSA.
3. Here in Ansa we majorly deploy the joints with the help of NASTRAN Decks. In the Nastran Deck, Bolts connection has been defined as RBE2, Spot Weld is defined as RBE2-HEXA-RBE2, this has been utilised in this challenge for deploying the connection in Rear Door of the car.
4. It is to be noted that where ever there is two hole of concentric parts, they must be connected through cluster RBE2 instead of bolts.
Procedure :-
1. The model was imported from the portal and studied. It was found out that model was defined in the sigle PIDs. Therefore the same was bifurcated to different PIDs
2. After the bifurcation it was studied that diiferent type of connections required in the model. following are the connections majorly done on the model :-
(a) cluster Joints amount two parts
(b) Hinge joints required at the door of the car. RBE2 (2 nodes) was used in this particular connections. In this type of connection on DOF ie arround the Z axis was not restricted as the door is allowd to rotate about z axis.
(c) Spot Welds. for doing this connection RB3 hexa RB3 was used in the nastran deck.
(d) Con Mass Connections given at the door Handle . It is to be noted that cluster RBE2 was deployed at two locations and then cluster node were connected with the single nodes. post this the mass of 100g in Tonnes was given on the connection. The mass was assigned to the connection with the help of NATRAN>>ELEMENTS>>CONMi.
(e) Bush Element was deployed arround both window glass of the rear door. After this thery were alligned to GCS of the ANSA.
CONCLUSIONS & LEARNINGS
1. For proper deployment of connections always bifurcate the single PIDs as per requirement. therefore the study of model must be through prior deployment.
2. Seam weld is to be done when the surfaces are parallel, Y joint weld conncetion is to be done when there is perpendicular surfaces. if the surfaces are being complicatedly oriented then spot welding may be prefered.
3. one should understand where to use cluster joint and where to use bolt joints. Zone cut should alwas be deploued on the cirular holes with more that 6 nodes.
4. Cbush must be alligned with the global coordinate system of the ANSA.