Duane:
Could you find out whether a Polywell reactor output can be increased or decreased while it is running? Also, how fast is it's startup sequence?
Mike
Questions about a notional all-up Polywell
Questions about a notional all-up Polywell
Vae Victis
What do you mean by start up sequence?
1. From atmospheric pressure
2. From vacuum with no fuel flow
3. From vacuum with fuel flow and cold electron guns
4. From vacuum with fuel flow and hot electron guns
5. From the time you turn on the HV
===
If you choose #5 it is in the range of 1 to 100 ms.
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Polywell should be able to be modulated by grid voltage and/or fuel flow.
How much? No one knows.
Estimates of max/min go from 1.1 to better than 9 to 1.
1. From atmospheric pressure
2. From vacuum with no fuel flow
3. From vacuum with fuel flow and cold electron guns
4. From vacuum with fuel flow and hot electron guns
5. From the time you turn on the HV
===
If you choose #5 it is in the range of 1 to 100 ms.
********************************************
Polywell should be able to be modulated by grid voltage and/or fuel flow.
How much? No one knows.
Estimates of max/min go from 1.1 to better than 9 to 1.
Engineering is the art of making what you want from what you can get at a profit.
If your talking about #1 above- starting from atmoapheric pressure.
It might take a few hours to a few days to pump down and condition the chamber (allow for outgassing of water, etc. from the walls).
If MSimon's 1:9 min/max power applies, with a ~ 1 ms startup time, a series of 10 reactors could throttle quickly between 1-90 X power. Of course a series of reactors would probably be less efficient(with more waste heat) than a single reactor. A more reasonable approach might be a low power reactor- say 50 MW used for regular power in a space ship, while a 5-10 GW reactor is used to power the engines when needed. This would allow more adaptability, and lower radiation loads while keeping a reactor (the little one) running. If the smaller reactor is placed between the big reactor and the rest of the ship, it could serve double duty by helping to shield ther rest of the ship without as much innert weight penalty. I suspect going much below ~ 20-30(?) MW maximum power reactors would be impratical as the excess energy (Q) would be getting uncomfortably close to breakeven .
Dan Tibbets
It might take a few hours to a few days to pump down and condition the chamber (allow for outgassing of water, etc. from the walls).
If MSimon's 1:9 min/max power applies, with a ~ 1 ms startup time, a series of 10 reactors could throttle quickly between 1-90 X power. Of course a series of reactors would probably be less efficient(with more waste heat) than a single reactor. A more reasonable approach might be a low power reactor- say 50 MW used for regular power in a space ship, while a 5-10 GW reactor is used to power the engines when needed. This would allow more adaptability, and lower radiation loads while keeping a reactor (the little one) running. If the smaller reactor is placed between the big reactor and the rest of the ship, it could serve double duty by helping to shield ther rest of the ship without as much innert weight penalty. I suspect going much below ~ 20-30(?) MW maximum power reactors would be impratical as the excess energy (Q) would be getting uncomfortably close to breakeven .
Dan Tibbets
To error is human... and I'm very human.
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