I am running multipass welding simulations. In the second or later welding steps, I frequently run into trouble with large deformations and elements turning inside-out, especially in the previous welding beads and the component material below the welding. Cause is obviously the low flow stress of the material at high temperature. Any good ideas for strategies on how to prevent simulations from crashing? Element deletion works, but the results are not satisfactory regarding stress results (see the image for an example).
Because the mechanical calculation is actually based on the thermal calculation. With the calculated temperature we use the material data at that temperature to calculate the stresses. In the thermal simulation one should ensure that the reached peak temperature is realistic (we recommend a value about 1.5 times of melting temperature of the material). Normally the inside-out elements are due to the too high temperature since the flow stress of the material is lower as you already known. By a heat source calibration you can check your temperature in advance without causing distortion.
If your peak temperature is fine, I would have to take a look at your model to find out what the exact problem is. Please send a test model with this problem to our support support@simufact.de and I will get back to you soon.
Because the mechanical calculation is actually based on the thermal calculation. With the calculated temperature we use the material data at that temperature to calculate the stresses. In the thermal simulation one should ensure that the reached peak temperature is realistic (we recommend a value about 1.5 times of melting temperature of the material). Normally the inside-out elements are due to the too high temperature since the flow stress of the material is lower as you already known. By a heat source calibration you can check your temperature in advance without causing distortion.
If your peak temperature is fine, I would have to take a look at your model to find out what the exact problem is. Please send a test model with this problem to our support support@simufact.de and I will get back to you soon.