## General Mechanical

#### Static coupled Transient Structural analysis

• Alpete
Subscriber
Hello all,nI'm trying to perform an impact analysis via the transient analysis module in Ansys Workbench. I have to preload some bolts and then check the effect of impact on these bolts. So I was able to solve for preload in the transient environment by switching off the time integration (for Time step-1) but I cannot apply velocity to the impactor as an initial condition in time step 2. I applied velocity at time step-2 (not as an initial condition) but Ansys converts the imparted velocity as a displacement and the velocity is applied gradually as a displacement.nMy target is to preload the bolts and then check for the integrity of the bolts via impact. But if I apply velocity as an initial condition, then I cannot capture the preloading of bolts.nIs there a way to import the prestressed setup from Static to Transient module?nIf not, how can I apply velocity to the impactor as an initial condition after preloading is accomplished?nAny help is much appreciated.nThanks in advance.nRegards,nAlpetenn
• Ashish Khemka
Ansys Employee
Hi Array ,nnPlease see the following link may seem useful to you:nn ,nnPlease see the following link may seem useful to you:nnnRegards,nAshish Khemkan
• Alpete
Subscriber
Hi Ashish,nThanks for the link. I tried the following and the corresponding results were seen.nTime step-1: Defined the Step End time as 1 with time integration off for preloading the boltsnTime step-2: Defined the Step End time as 2 with time integration off for locking of bolts (No external loads are applied here)nTime step 3: Defined the STep End time as 2.05 (0.05s is the time I want to evolve the transient impact period to) with time integration ONnI have assigned the impactor with velocity as an initial condition but the velocity is not getting impacted at time step-3 where the time integration is ON.nPS: I tried applying the velocity available in the structural loading section but the velocity is applied as gradual displacement but not as an initial condition.nThanks and Regards,nSantoshn
• Alpete
Subscriber
Hello Ashish,nI figured out the problem. nThe key lies in traversing the impactor to a distance to where it should actually by imparting a displacement and then deleting the displacement providing and then let the initial condition (i.e. velocity) come into force. nPrecisely what is told by Petroznewman in the link you provided earlier.nThanks for the help.nCheers!nn
• happykiran
Subscriber
Hi all,nI'm also facing the same problem and I followed these 3 steps nTime step-1: Defined the Step End time as 1 with time integration off for preloading the boltsnTime step-2: Defined the Step End time as 2 with time integration off for locking of bolts (No external loads are applied here)nTime step 3: Defined the STep End time as 2.05 (0.05s is the time I want to evolve the transient impact period to) with time integration ONnEven though the results are not satisfactory and stress values are not ramping up. (Bolt pretension was considered as impact load)nIs there any other approach to solve this problem?.