hari0811 1 Report post Posted June 1, 2016 I am trying to perform a simple drop test of ball on ground. (Both being Flexible and of same material (Steel)). The initial gap between ball and ground is 5mm. but when i see the animation file, the ball bounces after ~4.72mm. can some one please help me. steel_ball.avi Quote Share this post Link to post Share on other sites
hari0811 1 Report post Posted June 1, 2016 Starter and Engine Files. Test_0000.rad Test_0001.rad Quote Share this post Link to post Share on other sites
Guest Report post Posted June 2, 2016 Change the material type to M2_PLAS JOHNS ZERIL (elasto plastic material) and run the analysis. Provide appropriate material properties so that a realistic behavior of the simulation can be achieved. Quote Share this post Link to post Share on other sites
hari0811 1 Report post Posted June 2, 2016 ok I will launch using elasto plastic material and update you. But i am wondering how will that effect the physics of my problem. The ball should touch the other part and it should bounce back. Quote Share this post Link to post Share on other sites
Guest Report post Posted June 2, 2016 Material properties plays a vital role in simulation. The input parameters will define the weight of the component. So input a reasonable value of E and rho. Please update after the run. Quote Share this post Link to post Share on other sites
hari0811 1 Report post Posted June 2, 2016 Hello George I have tried using M2_PLAS JOHNS ZERIL and i have same problem. can you send me the your model from the picture Thankyou Quote Share this post Link to post Share on other sites
Guest Report post Posted June 2, 2016 Can you upload the model now Quote Share this post Link to post Share on other sites
hari0811 1 Report post Posted June 2, 2016 Test_Multilinear_0000.rad Test_Multilinear_0001.rad Quote Share this post Link to post Share on other sites
Guest Report post Posted June 2, 2016 Model the ground with elasto plastic material and run the analysis. Update it with the Plas Johns Zeril material. . Quote Share this post Link to post Share on other sites
hari0811 1 Report post Posted June 29, 2016 Hi George I have solved the problem, The problem was in GAPmin which was taking a default value because of which it was not coming into contact. Now i have a new problem which is drop in energy when the ball contacts with ground. ( My ground and Ball are flexible) Do you know why such thing happens ? Quote Share this post Link to post Share on other sites
Guest Report post Posted June 29, 2016 Please upload the deck file (0000.rad) and T01 file. Quote Share this post Link to post Share on other sites
hari0811 1 Report post Posted June 30, 2016 PFA the files. 8447.16_new_0000.rad 8447.16_new_0001.rad 8447.16_new_0002.rad 8447.16_new_0003.rad 8447.16_newT01 8447.16_newT02 8447.16_newT03 Quote Share this post Link to post Share on other sites
Guest Report post Posted July 4, 2016 Hi Hari, Can you check if there is any change in the KE Usually if the collision is a plastic collision there will be considerable KE loss due to plastic deformation. Also, total energy doesn't account for hourglass energy. So you may also have to check hour glass and contact energies. Quote Share this post Link to post Share on other sites
hari0811 1 Report post Posted July 4, 2016 Hello Prakash I am using Elastic model hence plastic deformation is not the problem, I just checked the contact energy, it has some energy which is the drop in energy. Total Energy = sum of internal energy + kinetic energy + external force work - Contact energy - hourglass energy - internal spring energy ? Is my understanding is correct ? Quote Share this post Link to post Share on other sites
