[AR] Re: Concussion Wind tunnel
- From: doug knight <dougchar001@xxxxxxxxx>
- To: "arocket@xxxxxxxxxxxxx" <arocket@xxxxxxxxxxxxx>
- Date: Thu, 4 Sep 2014 10:07:57 -0400
Just remember BATFE permits. Not an org that believes in forgiveness over
permission.
Doug K
On Thursday, September 4, 2014, Monroe L. King Jr. <
monroe@xxxxxxxxxxxxxxxxxx> wrote:
> The size of explosion I'm considering is several stix of dynamite.
> Dynamite is also cheap! With some kind of concrete apparatus. Perhaps
> something like a large concrete pipe in a mound facing the explosion.
>
> Monroe
>
> > -------- Original Message --------
> > Subject: [AR] Re: Concussion Wind tunnel
> > From: Norman Yarvin <yarvin@xxxxxxxxxxxx <javascript:;>>
> > Date: Thu, September 04, 2014 5:38 am
> > To: arocket@xxxxxxxxxxxxx <javascript:;>
> >
> >
> > On Wed, Sep 03, 2014 at 10:57:15PM -0700, David Weinshenker wrote:
> > >Ben Brockert wrote:
> > >> There are times when wind tunnels give much better data than FEA, but
> > >> for modeling something that is rotationally symmetric through a small
> > >> range of operable flight angles the data from FEA is going to be a lot
> > >> more accurate than something like trying to use an explosion as a very
> > >> transient wind tunnel.
> > >
> > >Don't many supersonic tunnels inherently operate in a "very transient"
> > >mode? I thought that was a common characteristic of such systems...
> >
> > More like "transient" than "very transient". The idea is something
> > like "we compressed a lot of air on one end, and pulled a vacuum on
> > the other end, and got supersonic flow for a fraction of a second
> > after breaking the separating membrane", not "we were trying to get
> > data from a shock wave whose thickness is measured in microns".
> >
> > (Shock waves are closely followed by expansion waves, after which the
> > gas slows back down. With really huge explosions -- as in, nuclear --
> > there can be a serious distance between the two, but for anything an
> > experimenter in the same room can survive, the distance will be
> > microscopic. See
> >
> > Atom Bomb explosion (HQ)
> <https://www.youtube.com/watch?v=Qn5vysBkWdM#t=75>
> >
> > then imagine that on a much, much, much smaller scale.)
> >
> >
> > --
> > Norman Yarvin http://yarchive.net/blog
>
>
Other related posts:
