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satriani May 18, 2011 03:53

Propeller airplane
 
I have to run a simulation of a propeller driven airplane at takeoff, i read the tutorial on how to simulated the rotation of a part (in my case the propeller) with rigid body motion and the tutorial in wich one has the boat and wants to simulate its motion with the 6-DOF model. In my case how i can use both the 6-DOF to study the motion of the airplane and rigid body motion to simulated the rotation of the propeller? From the physics model selection it seems i can only use one of them... thanks!

nomad May 20, 2011 12:45

You don't need to use the DFBI model.

Assign the prop to a rotating region with an interface (I assume you know how to setup interfaces?) to the non-rotating region to which the airplane belongs. Make sure the prop is detached from the airplane by making a thin cut between the two.

You only need one physics model, either MRF or RBM, which will allow you to assign an rpm to the rotating region, and a freestream velocity to the non-rotating region.

Use the steady state MRF model (faster convergence) first until converged, then turn on the implicit unsteady RBM model (slower convergence) with an appropriate time-step (depending on mesh resolution and rpm) for a couple of revolutions until the wake is fully developed. The RBM model gives a better torque-thrust result than the MRF for Re<1e6 cases, given the right mesh resolution of course.

satriani May 23, 2011 03:12

I've made the two regions detached and set the RBM model, but know i want to simulate the motion of the airplane. To do this i've create another physics with the 6DOF model enabled but i don't know what to do next. Anyone can help me? thank you


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