Talk-Polywell.org

Speculation, but an engine failure could be simply due to running out of fuel/ oxidizer. Resultant vapor lock or other cause of decreased fuel mixture flow leads to lower thrust. How syncronized is fuel starvation to the three landing engines (or is it on?)? Would plumbing, tilt, etc. allow one engi...

I wonder if it would make more sense to launch the first reused booster with a consumable payload for the ISS ahead of the scheduled ones. Such a payload is very likely a lot cheaper than a satellite and sending one up before it's needed would mean it's loss wouldn't be a big problem if it fails. T...

My money saving scenario is supposition but it does seem likely. I also speculate that using a used first stage with minimal modifications, appropriate ballast, etc. could be used to boost the Dragon II for spacecraft escape testing. I think Space X currently plans to use a modified second stage for...

Solar photovotaics have historically been narrow bandpass- using only a relatively narrow wavelength range compared to the total solar radiation. But wider bandpass materials and multiple staged bandpass materials are being pursued. While not a power harvester per say, I was intrigued by a proposed ...

I don't know if this is redundant or useful but the advancement of harvesting heat energy continues... http://phys.org/news/2016-06-electricity-dimensions.html I am a fusion fan boy, but as I have mentioned in the past, as photovoltaics and thermal conversion of Solar output improves, any fusion out...

Risks are in proportion to benefits. SpaceX apparently have highly instrumented rockets- this allowed them to quickly pinpoint the failed component in their RUD launch last year. Also, ground testing puts stresses on the spacecraft that again presumably gives substantial information and predictive p...

PS: I am getting in the habit of using the term of diffusion for ExB losses. This is because it is much like gas diffusion except for the quantification due to the B field strength and associated gyroradius jumping. Transport is also commonly used, and I think it is included in the group of 'classic...

Some interesting interactions pushed. Problems may be m ostly scaling. An ion rich core contained by physical magnetically shielded cathodes seems reasonable, but... Bussard stressed that for useful fusion power independant of Q you must have a considerable density of ions. This is one of the keys ...

Some interesting interactions pushed. Problems may be m ostly scaling. An ion rich core contained by physical magnetically shielded cathodes seems reasonable, but... Bussard stressed that for useful fusion power independant of Q you must have a considerable density of ions. This is one of the keys o...

It would seem to me that this is something one could plan for and easily repair or just shim up According to Musk, the crush core can be replaced easily. Indeed replacement back at the Cape is probably trivial. A temporary fix while at sea might utilize jacks and shims. Probably easy with calm seas...

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If I remember correctly, Tri Alpha roughly achieved 1keV plasma temperature so far. Pulsed FRC devices like some of Helion's prototypes have routinely achieved over 5 keV. So it seems relatively plausible that Tri Alpha will achieve the temperatures, they need. What worries me a bit, is that their ...

People are already over interpreting this comment. We do not know how bad the damage really was or how much of that stage can be reused. All that Musk said was that the stage is now their now baseline for ground testing since it was the one that was damaged the most of the 3. Merely speculation bas...

Very quick compression of a fusion substrate may produce a plasma of such density that the few alphas produced would not escape but thermalize with the fuel and drive a progressive heating of the plasma till the fuel was depleted (or some useful subset). This chain reaction concept seems simple. Geo...

As a tangential consideration- I wonder if the cluster of 9 engines on the Falcon 9 has any effect of the effective nozzle exhaust expansion of the engines. Sort of like Arospike designs where performance in dense atmosphere and space both are optimized. The images of the Falcon 9 in the latter stag...