Interesting fin design stability report

[shockie]

This might come in handy for scratch builders:

Effects of Different Fin Shapes on Apogee and Stability of Model Rockets.

 

[SolarYellow]

Scanned it quickly. Basically, they played with OR and generated some graphs of the results, which one can figure out very quickly just by playing with OR. Thicker fins hurt apogee, thinner fins help. Fin sweep angle helps apogee. Increasing fin span hurts apogee but increases stability.

I don't think they even mentioned other considerations that are really important, such as mechanical strength and needing to prevent flutter.

 

[Art Upton]

And do I know about even with proper mechanical strength, flutter on a flat plate design can still take them out.

 

[user 30299]

Scanned it quickly. Basically, they played with OR and generated some graphs of the results, which one can figure out very quickly just by playing with OR. Thicker fins hurt apogee, thinner fins help. Fin sweep angle helps apogee. Increasing fin span hurts apogee but increases stability.

I don't think they even mentioned other considerations that are really important, such as mechanical strength and needing to prevent flutter.

If you check the report's "References" you will see one of the authors has an earlier report on fin flutter.

 

[SolarYellow]

If you check the report's "References" you will see one of the authors has an earlier report on fin flutter.

https://www.researchgate.net/profil...odel-Rocket-using-Response-Surface-Method.pdf

 

[lakeroadster]

It's a report on the "Effects of Different Fin Shapes on Apogee and Stability of Model Rockets"...

not "The Complete Guide for Fin Design & Construction".

Thanks for the thread @shockie

 

[Buckeye]

This might come in handy for scratch builders:

Effects of Different Fin Shapes on Apogee and Stability of Model Rockets.

Not bad. I like the Response Surface Model approach, but I wish they did more with it than just main effects. I would have been interesting to see them use it to predict an optimum or the pareto front between altitude and stability. More info on how the RSM was constructed seems necessary, also.

 

[kjhambrick]

Buckeye --

Yes, the Response Surface Model graphs are an effective method to visualize the interdependence of three variables.

But I am with you ... I skimmed but did not study the Paper but I did not see the punch-line.

And I would like to know: CD -vs- Mach Number and Fin Thickness aside, what fin shape and geometry stably lofted the 8-Kg Payload to the highest altitude ?

-- kjh

 

[lakeroadster]

Buckeye --

Yes, the Response Surface Model graphs are an effective method to visualize the interdependence of three variables.

But I am with you ... I skimmed but did not study the Paper but I did not see the punch-line.

And I would like to know: CD -vs- Mach Number and Fin Thickness aside, what fin shape and geometry stably lofted the 8-Kg Payload to the highest altitude ?

-- kjh

It's an exhibition... not a competition, so please no wagering.

It's also not a build thread... it's a research paper.

 

[kjhambrick]

I guess I what I said was unclear .

I liked the paper

-- kjh