AnsweredAssumed Answered

Multiple Questions About Flow Simulation

Question asked by Jameson Gavac on Nov 2, 2014
Latest reply on Aug 20, 2015 by Amit Katz

Hey everyone, I've been having some issues trying to use Flow Simulation, and I have a couple questions. I'm working on modelling how air would flow and the pressure differentials inside of a CVT cover. Since we are having power loss because of excess heat, we are exploring a few different ways to do this. One of them that I am working on now, is having an alternator fan attached to the primary clutch. I've been learning flow sim along the way, but I've got some problems.


First off, when using the detailed models of the primary and secondary clutches that the company we buy from provided us, I am unable to select them to assign a rotating region. From what I can tell, it has something to do with the complexity of the part? Because if I use a completely smooth dummy model (no fan on the primary), I can assign rotating regions no problem and the simulation will run. Unfortunately that doesn't do me any good, since the dummy models are a lot different from the actual parts. The clutches have a lot of features and gaps where air will get chopped up, in addition to having the fan on front moving air.


These are the models I'm trying to use

Primary and secondary no case.PNG


The case that encloses them

With case.PNG


These are the dummy models that work with flow sim. Primary on the left (notice no fan), and secondary on the right.




Second off, when I run the flow sim with dummy parts, the flow trajectories originate in the middle of the primary instead of the assigned inlet, the trajectories do not go to the assigned outlet, and they frequently clip through my parts. I can't figure out why this would be happening, so any insight would be helpful.


Notice the flow is starting in the middle of the secondary, instead of coming in the inlet (cap in front of primary). The fan is attached in this one, but the model isn't rotating.

Flow start.PNG



Here we can see the massive amounts of clipping through the pulley halves on the secondary, as well as where the spring body would be.

flow clipping.PNG


If anyone could help, I would greatly appreciate it