We have a computer model of the Tesla Roadster. We calculated the forward thrust provided by the cold gas thruster, then added that thrust to the forward thrust from the front and rear axles and re calculated the accel times.
I figured a specific impulse of 60 sec. Thats a bit lower than wiki quoted for an N2 cold gas thruster
Cold gas thruster - Wikipedia
I then jst used the eqn: F= Isp times the mass flow rate
Specific impulse - Wikipedia
I figured a 100 lb of compressed air (mostly N2) dischardged in 5 seconds for a mass flow rate of 20 lb/sec
so F=60sec times 20 lb/sec=1200 lb thrust
Then I used our perf program for the roadster and just added 1200 lb forward thrust and also a calc for 2400 lb of added forward thrust (dump the 100 lb of air in 2.5 sec or add another tank and thruster).
So 0 -60 times for the single thruster decreased 0.3 seconds
and around .5 seconds for the dual thruster
Our basic program shows a total forward thrust supplied by the front and rear axles of around 6400lbf.
So to put the thruster amount in perspective, It's 1200 lbf on top of 6400 lbf....a 19% bump.
Pretty crude but it gives you a general idea of how much the cold gas thrusters are worth.
If you spot any errors in the math let me know in the comment section.
Thanks,
George
I figured a specific impulse of 60 sec. Thats a bit lower than wiki quoted for an N2 cold gas thruster
Cold gas thruster - Wikipedia
I then jst used the eqn: F= Isp times the mass flow rate
Specific impulse - Wikipedia
I figured a 100 lb of compressed air (mostly N2) dischardged in 5 seconds for a mass flow rate of 20 lb/sec
so F=60sec times 20 lb/sec=1200 lb thrust
Then I used our perf program for the roadster and just added 1200 lb forward thrust and also a calc for 2400 lb of added forward thrust (dump the 100 lb of air in 2.5 sec or add another tank and thruster).
So 0 -60 times for the single thruster decreased 0.3 seconds
and around .5 seconds for the dual thruster
Our basic program shows a total forward thrust supplied by the front and rear axles of around 6400lbf.
So to put the thruster amount in perspective, It's 1200 lbf on top of 6400 lbf....a 19% bump.
Pretty crude but it gives you a general idea of how much the cold gas thrusters are worth.
If you spot any errors in the math let me know in the comment section.
Thanks,
George