To: Brett66
I wonder what the full potential of this technology could be if we got serious and invested a couple billion a year in the development of ion propulsion. Deep Space1 put out 90 millinewtons of thrust, this is putting out around .9 Newtons of thrust with an ISP of >6000. Could we get this past 10,000-20,000 ISP with around 100 Newtons of thrust? A technology definitely worth investigating. What the hell did you just say?!
English Please?
To: unix
More power! Better gas mileage!
19 posted on
11/20/2003 8:47:05 PM PST by
Brett66
To: unix
Let's say this engine's thrust was scalable to space shuttle power levels. If you had an specific impulse of 20,000 you would only need 1/44th the fuel to reach the same velocity.
24 posted on
11/20/2003 8:50:56 PM PST by
Brett66
To: unix
I wonder what the full potential of this technology could be if we got serious and invested a couple billion a year in the development of ion propulsion. Deep Space1 put out 90 millinewtons of thrust, this is putting out around .9 Newtons of thrust with an ISP of >6000. Could we get this past 10,000-20,000 ISP with around 100 Newtons of thrust? A technology definitely worth investigating.What the hell did you just say?!
English Please?
I think it translates as...
Even with improvements, the Ion engine can't lift it's own weight off the ground, although it can "push" itself on a fairly level, smooth surface..
Given a weightless environment, and millions of miles to accellerate, it can reach incredibly high speeds, however.
Highly charged ions reach an exit speed much higher than chemically powered particles. (rocket fuel exhaust)
Ion engines are best used in a hybrid system.
In such a system, chemically fueled rockets would act as "low" gear, providing the torque for getting the vehicle /load moving, and up to a fairly good velocity. ( up to 10g, or 10 x gravity )
The Ion engines would then take over the long haul work, increasing velocity at a much lower thrust, (1 to 2 gravities) but able to reach much higher speed over time.
At least I think that's what he said.
52 posted on
11/20/2003 10:14:06 PM PST by
Drammach
To: unix
English Please? It is English. There are over 2 million words in the English language. The average high school graduate knows 20 thousand. Some words require additional study since they have precise technological meaning, and misuse of such words can be expensive. OTOH, misuse of the 2000 words known to be in the vocabulary of most Democrats and Radical Left is deliberate and is intended to create objective confusion.
91 posted on
11/21/2003 9:13:00 AM PST by
RightWhale
(Close your tag lines)
To: unix
>Deep Space1 put out 90 millinewtons of thrust, this is putting out around .9 Newtons of thrust with an ISP of >6000.
Could we get this past 10,000-20,000 ISP with around 100 Newtons of thrust? A technology definitely worth investigating.
What the hell did you just say?!
English Please?
OK.
ISP is specific thrust:
This is: thrust (pounds, for instance) for a time (seconds) per mass of propellant (kg, for instance).
So, Deep Space 1 has Isp of 3,100:
That's a thrust of about .1 newton (or .022 pounds) for 310,000 seconds for each kg of propellant.
Thus, (for instance - numbers not exact) the earlier Deep Space 1 100 kg of propellant will run for 30 million seconds
or more than a year with a thrust of less than an ounce.
It has run for at least 40 million seconds or used 127 kg of propellant.
Long-distance interplantary probes can use low thrust for long periods. They minimize the propellant mass (for efficiency) and maximize the acceleration of the propellant (no 'burning' reaction, only an electrostatic charge which accelerates an ion).
The ion engine is like the solar sail concept in that it uses low power over a long time. A spacecraft of small mass can accelerate over time.
For the example above, a 100 kg craft for 450 days would get to more than 90,000 miles per hour. (but would typically spend half the travel time decelerating).
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