General Mechanical

Setting up Topology Optimization problem to achieve displacement in cylindrical coordinate system

• as880
Subscriber

Hi guys so I want your advice upon setting up topology optimization.

Problem: set up TO in such a way that the output connects body 1 and body 3. i.e body 2 is my design inclusion region and 1 & 3 are my exclusion region. circular holes are fixed pins that hold the structure in place that i have modelled as fixed supports. 100Nm torque is applied through the big hole in the middle. All 3 bodies have shared topology and are of the same material.

Desired solution: the connecting structure of body 2 will deflect by around 5 deg (0.00307 rad)

My thought process: I think that i can measure this deflection by setting up a new cylindrical coordinate system at the circumferential face of body 1 and the axis that goes around y axis lets say.

I will then measure this deflection by the rule THETA = L / R where R is the radius of body 1 from the centre point. and L will be the output direction deformation along the cylindrical axis (y axis)

This then means i should set up a minimize compliance objective and set up a displacement constraint to get my 0.00307 rad deflection ( displacement i need = 0.00307 * R)

• 1shan
Ansys Employee
nFirst you need to create a nodal named selection. The right-click static structural nodal orientation, this is where you relate your cylindrical coordinate system to the nodal coordinate system. This https://www.padtinc.com/blog/node-interaction-in-mechanical-part-3-nodal-boundary-conditions/ should help you do that. Once you have a nodal coordinate system you could insert a displacement constraint. Also a cyclic constraint would be a better option. You could also try using a min-max member size constraint to set dimension of a the strut. nRegards,nIshan.n
• as880
Subscriber
Hi Ishan, nI have created a named nodal selection and then orientated it as well but the choice is still not coming up.. is there any other way i can tackle this problem?nn