A bit of bar-napkin rocketry... N2 cold gas thruster theoretical vac
Isp is 80 seconds. Guesstimate 70 seconds with real-world losses and 1
atm back pressure (almost negligibly low compared to the thousands of
psi chamber pressure.)
Air at sea level masses ~.08 lb per cubic foot. Figure you might fit a
~12 cubic foot air tank into the back seat of a Tesla, ~2 ft diameter x
~4 feet long. At ~300 atmospheres or ~4500 psi, that's ~300 lbs of
air. Figure with a little engineering you can use 2/3rds of that before
thrust starts tailing off too much.
At Isp 70, 200 lbs of air translates to 14,000 lb/seconds of thrust. Or
~400 lbf thrust for 35 seconds. Enough to do some fancy thrust-assisted
maneuvering, yeah.
Henry
On 9/20/2019 6:48 AM, Galejs, Robert - 1007 - MITLL wrote:
Any idea of what sort of thruster specs would be practical with such a setup?
*From:*arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> *On Behalf Of *Darren Longhorn
*Sent:* Friday, September 20, 2019 9:39 AM
*To:* arocket@xxxxxxxxxxxxx
*Subject:* [AR] Re: Tesla Thruster Specs?
My understanding is that they will be compressed air, fed from a tank where the rear seats would have been.
On Fri, 20 Sep 2019, 14:17 Galejs, Robert - 1007 - MITLL, <galejs@xxxxxxxxxx <mailto:galejs@xxxxxxxxxx>> wrote:
Tesla appears to be planning some sort of cold gas thruster option
for their new roadster model…
… See
https://insideevs.com/news/350682/tesla-roadster-spacex-thrusters/
for example…
… but I can’t find anything definitive about what these thrusters
are planned to look like. On one car enthusiast Facebook group I
subscribe to, someone was claiming that Tesla was planning to put
ten 400 lb thrusters around the vehicle which would be capable of
firing for 90 seconds, which sounds silly just thinking about the
mass of nitrogen required.
Does anyone here have any information/informed-speculation they
could share about these potential Tesla thrusters?
Thanks,
Robert