Quick and Dirty Aerodynamics

Having fun with the WindTunnel app - looking at various aerodynamic concepts and geometries.

[Quick and Dirty Aerodynamics @QADaero]

[1/2]Aero Fallacies- Equal Transit Time. Common explanation of lift, states air from LE must meet at TE and longer upper path leads to higher speed & lower p. No reason for this and sim shows that upper air reaches TE first. #aerodynamics #aerospace #Engineering #STEM #aviation

[Quick and Dirty Aerodynamics @QADaero]

The failure of my rocket glider was partially down to balance/stability issues => been very careful with my rc plane & built a rig to find CoG. Good job as with camera/altimeter it is ~23mm forward of optimum/17 from acceptable. #AvGeek #aircraft #aviation #Engineering #stem

[Quick and Dirty Aerodynamics @QADaero]

Finally got my control surfaces operating in the right direction... Just waiting for Boris now! #flying #AvGeek #model #rcplane #STEM #aviation

[Quick and Dirty Aerodynamics @QADaero]

@MarkLaneF1 Thanks Mark! Reminds me, I haven't used that app in months...

[Quick and Dirty Aerodynamics @QADaero]

@smithharry I wouldn't be surprised, they always looked after their key employees...

[Quick and Dirty Aerodynamics @QADaero]

12022021

[Quick and Dirty Aerodynamics @QADaero]

Excellent news, very much looking forward to this. I am about half through the first book, and have found it absolutely fascinating - packed full of technical drawings, graphs and information about a subject it turns out I'm much more ignorant about than I thought! 👍

[Calum E. Douglas FRAeS @CalumDouglas1]

Well, thats book #2 done, by the time Dr Gülen and I finished adding explanatory material, Prof. Dr-.Ing Kollmann`s previous unpublished 1947 technical memoirs (now in English) from Daimler-Benz ended up as another 450 page tome. To be published later this year by @ASMEdotorg.

[Quick and Dirty Aerodynamics @QADaero]

@TerenceCGannon @wndxlori @TheBrianMcManus @reneritchie @NASAhistory @NASA I just clicked on @TheBrianMcManus and realised that I've completed a hillarious loop - turns out I found the links for that book and the papers on his YouTube video (created after the original tweet)!!! 🤣🤣 It's an excellent video, very well explained & thanks for the refs. 👍

[Quick and Dirty Aerodynamics @QADaero]

@TerenceCGannon @wndxlori @TheBrianMcManus @reneritchie Sorry only just saw this, I didn't know much more than what others have said, but did a bit of research and found this book https://t.co/DTUhRQBkeJ and these nasa papers https://t.co/nuv4p8nZCL https://t.co/P1L4fr6Avw  . Ive not gone through them yet, but look interesting.

[Quick and Dirty Aerodynamics @QADaero]

@RocketBanana Sorry, just saw this message.That would be great to do, although as my local uni is Cranfield (I live the other side of the airfield) I probably should improve the build quality 1st 😅 I would have loved to have done something similar when I was at uni, all we did was aerofoils..

[Quick and Dirty Aerodynamics @QADaero]

[1/6] Rocket Flight Testing & Correlation. I have carried out flight testing with an altimeter and plotted vs calc. There are obvious differences between graphs including apogee and decent rate- I've looked at parameter mods to match real life #Rocket #STEM #avgeek #Engineering

[Quick and Dirty Aerodynamics @QADaero]

Half speed, watch the bounce!

[Quick and Dirty Aerodynamics @QADaero]

How to turn 1 rocket launched glider into many gliders... actually happy with most of the flight (separation worked even at high speed), just had too long a delay after burn #rocket #Engineering #AvGeek #STEM #Aerospace

[Quick and Dirty Aerodynamics @QADaero]

@aerodymagic Agreed, especially as this is only a sample of 1. Would be much better to make multiple launches and compare all the data

[Quick and Dirty Aerodynamics @QADaero]

@aerodymagic [2/2] in isolation and see if any small change would have a large effect, but as you mentioned large shifts are required. I did snap a fin in a previous flight and the repair ended up very squint which could acount for a significant drag penalty plus effect trajectory/dynamics.

[Quick and Dirty Aerodynamics @QADaero]

@aerodymagic [1/2] Hi, yes I very much agree with all your points, especially that its going to be a combination of effects and also angle to the vertical, although there was absolutely no wind that day. As a starting point, my plan here was to carry out a sensitivity sweep on each parameter

[Quick and Dirty Aerodynamics @QADaero]

[6/6] Comments - In addition, other factors are flight not purely vertical, launch rod friction, spin etc. Mass was measured & motors are ~controlled, so I'd guess that drag is primary factor for calc vs flight delta, especially as build quality was poor (surface, fin spacing)

[Quick and Dirty Aerodynamics @QADaero]

[5/6] Parameter Sweep 4 - Parachute Drag Coefficient. I had to double the parachute drag coefficient to match the decent rate.