how to simulate railbutton in RockSim

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Hello all, I have search here and on the Apogee site, but don't see any info on how people simulate the aero affects of 1010 rail buttons on a flight. I know I can add a mass object, but I am wondering if anybody is using a method of modeling rail buttons that will change the aerodynamics of the rocket. I have played around with a launch lug with .01mm inside diameter (can't be zero), but hope to find a more accurate simulation. Thanks.
 
There are a couple methods. The one I use is this. I calculated the frontal area of the rail guide, and made a solid tube of the same area. It is not exact, but will get you close.

The other method would to build a subassembly likely using pods.
 
Hello all, I have search here and on the Apogee site, but don't see any info on how people simulate the aero affects of 1010 rail buttons on a flight. I know I can add a mass object, but I am wondering if anybody is using a method of modeling rail buttons that will change the aerodynamics of the rocket. I have played around with a launch lug with .01mm inside diameter (can't be zero), but hope to find a more accurate simulation. Thanks.

You can import the RockSim file into RASAero II. (See Pages 39-42 of the RASAero II Users Manual for importing RockSim files). RASAero II has an accurate Rail Guide drag model. Many of the rockets on the Comparisons with Altitude Data page on the RASAero web site have Rail Guides.

https://www.rasaero.com/comparisons-alt.htm

When you import the RockSim file into RASAero II, you'll have to make sure to update the Fin Airfoil data for your rocket. RASAero II has additional Fin Airfoils not available in RockSim, another thing that will give you increased accuracy for your altitude predictions.


Charles E. (Chuck) Rogers
Rogers Aeroscience
 
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