DFBI Superposed rotation inside overset mesh.
 

Hey guyz,
I want to find the trajectory of a propeller driven aircraft. So i am thinking of using overset meshing and by giving DFBI to the whole aircraft body and giving DFBI superposed rotation to the propeller. so is it possible?

thanks in advance.

yes this is possible

so we can have sliding mesh inside overset mesh? i thought since overset mesh performs the hole cutting process, we cannot use sliding mesh inside an overset mesh.

if you need me to say yes again then yes it can be done and was shown at the global conference this year

and if you are using a recent version eg 9 you can can overlapping overset meshed regions which means the propellor could be in an overset region inside the other overset region rather than within a sliding rotation region

actually i am simulating an airship in which there are two propellers attached to its body through two suporting rods. now to provide thrust vectoring these two rods can be swiveled around and change the angle of thrust of the propeller. so to model this i was thinking of using overset mesh, but for the rotation motion of the rods and propellers, i need to use sliding mesh. also i am thinking of using dfbi motion to find out its trajectory.
i have posted a question on this with some fotos in this thread.
http://www.cfd-online.com/Forums/sta...rset-mesh.html

please take a look at this.
thanks in advance for ur help.

So when i did all this i could not align the propeller and rod with the motion of the airship. so what should i do to align the region of the rod rotation and propeller rotation with the airship?

you use two motions being a normal dfbi rotation and translation and a dfbi superimposed rotation and apply this second one to the propeller region and add the propeller surface to the dfbi body parts

as i mentioned earlier i am simulating a case in which the propeller is rotating as well as swiveling, i.e. providing thrust vectoring to the airship. in this using dfbi superimposed roation will not work. i tried using rotation for swiveling and then superposed rotation for rotation of propeller but inspite of keeping the coordinate system of the motion of the propeller aligned with the swiveling motion and also keeping the swiveling motion aligned with the airship, i could not able to align the propeller to the airship movement and everytime the propeller just moves away. what should i do?

i have not done this within dbfi and suggest you ask support about it