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[aman7]

Hello experts,nI am trying to simulate Hopkinson bar experiment. in simulation i do not want to simulate striker bar. I have the incident strain in incident bar from the experiment. In explicit dynamics, there is no option to give strain as loading. Thus I converted the incident strain to incident stress By linear relation stress = E x Strain, as the long bars remain elastic during experiment. Then I have applied stress value as pressure to the incident bar face where striker strikes. The bars are restricted for displacement in Y and Z direction and free in X-direction (along length). nIn results when i plot the strain in the bar, it is not the same value and less then the strain applied as pressure.nCan some one guide me how can i Give strain loading ?n

[1shan]

,nThe stress in a dynamic condition is different from that of a static condition(usually twice or higher). If you want to find the equivalent stress which would replicate the dynamic scenario than you need to multiply it by an impact factor. Check this out https://www.clear.rice.edu/mech403/HelpFiles/ImpactLoadFactors.pdf. You could convert the strain into displacements and insert a displacement load. I doubt if this would work since the strain is accompanied by accelerations (you need both the data). You may try to increase the pressure until you get the required experimental strain and use that for the analysis.nRegards,nIshan.n

[aman7]

Thank you for your reply. n