RE: [deal.II] Questions on Step-18

ct: Re: [deal.II] Questions on Step-18 HI Michael, I’m not the original author of step-18, but I think that I’ve found some sources that can explain both the construction of the non-normalised rotation axis w and the angle θ calculation. 1. Axial vector ω (the non-normalised axis of ro

Re: [deal.II] Questions on Step-18

the rotation rate >> (angular velocity) but the infinitesimal rotation tensor gives the rotation >> angle (curl of displacement). Do correct me if I’m wrong. >> >> Now I’m excited to learn how to make my first patch. >> >> - Michael >> >> From: Je

Re: [deal.II] Questions on Step-18

om: *Jean-Paul Pelteret > *Sent: *Saturday, June 26, 2021 2:57 PM > *To: *dealii@googlegroups.com > *Subject: *Re: [deal.II] Questions on Step-18 > > Hi Michael, > > What’s written in the implementation suggests that computing the curl of > the displacement (increments) is

Re: [deal.II] Questions on Step-18

to learn how to make my first patch. > > - Michael > > From: Jean-Paul Pelteret <mailto:jppelte...@gmail.com> > Sent: Saturday, June 26, 2021 2:57 PM > To: dealii@googlegroups.com <mailto:dealii@googlegroups.com> > Subject: Re: [deal.II] Questions on Step-

RE: [deal.II] Questions on Step-18

the rotation angle (curl of displacement). Do correct me if I’m wrong. Now I’m excited to learn how to make my first patch. - Michael From: Jean-Paul PelteretSent: Saturday, June 26, 2021 2:57 PMTo: dealii@googlegroups.comSubject: Re: [deal.II] Questions on Step-18 Hi Michael, What’s written

Re: [deal.II] Questions on Step-18

Hi Michael, What’s written in the implementation suggests that computing the curl of the displacement (increments) is the right thing to do in this instance: > Nevertheless, if the material was prestressed in a certain direction, then > this direction will be rotated along with the material.

Re: [deal.II] Questions on Step-18

I would be happy to do the comparison and make the fix. But before doing that, I want to make sure I understand the formula correctly. When we calculate the rotation matrix, it seems that the *du* (incremental displacement) is used. // Then initialize the FEValues object on the present

Re: [deal.II] Questions on Step-18

Following Andrew’s explanation, I suppose that this is relation for which we’re lacking the factor of 1/2, right? https://en.wikipedia.org/wiki/Angular_velocity#Angular_velocity_as_a_vector_field If so, then

RE: [deal.II] Questions on Step-18

the code roll. Thank you again for your wonderful help! Best,Michael  From: Jean-Paul PelteretSent: Thursday, June 24, 2021 11:43 PMTo: dealii@googlegroups.comSubject: Re: [deal.II] Questions on Step-18 HI Michael. To be honest, I have a hard time to understand the three-filed formulation in Step 44

Re: [deal.II] Questions on Step-18

simpler and help me > understand more complex nonlinear models. Meanwhile, I try to compare the > results with a reference which only consider the geometrical nonlinearity. > > -Michael > > > From: Andrew McBride <mailto:mcbride.and...@gmail.com> > Sent: T

RE: [deal.II] Questions on Step-18

GroupSubject: Re: [deal.II] Questions on Step-18 Hi both, Jean-Paul has addressed the second point nicely. On the first point, I think there is a 1/2 missing. The curl of the velocity gradient is the vorticity which is twice the angular velocity - hence I think you need a 1/2. Happy to be corrected

Re: [deal.II] Questions on Step-18

Hi both, Jean-Paul has addressed the second point nicely. On the first point, I think there is a 1/2 missing. The curl of the velocity gradient is the vorticity which is twice the angular velocity - hence I think you need a 1/2. Happy to be corrected on this. Best, Andrew > On 24 Jun 2021,

Re: [deal.II] Questions on Step-18

Hi Michael, I cannot comment on the first question, but might be able to assist a bit with the second. But may I first ask, what precisely are you trying to achieve with this extension? As interesting as it is, in the past I had found step-18 to deviate too significantly from the “classical”

[deal.II] Questions on Step-18

Hello, I have two questions when studying Step-18. 1) Should there be a factor 1/2 when calculating the rotation matrix angle (code in tutorial: angle = std::atan