Yep, I'll be here!
7:00 in the conference room in FAB 84.
On Thu, Oct 23, 2014 at 10:15 AM, Erin Schmidt <es...@pdx.edu> wrote:
> Hey guys,
> I'm having some rather painful migraines which are leaving me doubtful that
> I'll attend tonight's propulsion meeting. AFAIK Nathan is still going, so
> tonight would be a good time to actually compare designs in open rocket.
> Keep in mind that changing the fin dimensions or adding ballast to the nose
> cone is fair game if your design isn't stable in flight (recall that
> stability is a function of the positions of the center of mass and the
> center of pressure, both of which are changing dynamically with time,
> velocity, angle of attack, altitude, and also with reynolds number and mach
> number among other things). It's okay if its not totally stable for the
> first half second or so right off the launch rail (assuming that it doesn't
> ruin your simulation). If somebody is able to get a legit design to 100 km,
> take the burn time and rocket dry mass to get the mass ratio, and plug that
> back into the rocket equation to compare with our super simple 1.4 km/s dV
> estimate. My bet is it will be 1.5X-2X as high.
> I'm guessing the 100 km rocket with steel tanks isn't doable for us in a
> single stage. But I'm curious if we can pull it off with aluminum. We also
> assumed a pressure fed rather than pump driven propellant feed system, which
> is good because if anything this means our current numbers will be
> pessimistic (because we are using a design calling for heavier, high
> pressure tanks). I'm hoping this whole exercise will give you an intuitive
> appreciation for how ridiculously parameter sensitive rocket design is.
> Ad astra,
> Erin Schmidt
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