I've never said the 10% number is anything but arbitrary. I guess it depends on where one defines the launch mechanism as "inefficient.">>
Exactly...so stop expecting us to accept your arbitrary definition.
>> In this case, My suggestion is that 90% is pretty efficient. >>
Not in my opinion. .....
For now, I guess what is or isn't "efficient" is about all that matters for us to discuss...i.e. whether your arbitrary 90% number is "generous" (as you imply) or "stingy". We are NOT talking about types of engines or fire hoses (which has not been mentioned by me on this site) splattering on fences. We have already agreed that the heat transfer to the atm during launching is negligible.
The best efficiency I know of is 97-98% in a rocket engine. They use nozzles that are carefully designed to maximize thrust; precision machined; and fine tuned during launch to optimize efficiency. You suggest 99.95% with a horizontal blast of material at a fragmenting rock wall. I think your expectations are a bit high.
I don't understand why you keep repeating the mantra about heat transfer during launch. That is not, was not, and never has been an issue. The issue isn't launch, it's the fall back.
ALL we need to focus on is whether the process of "shutting off" could be done quickly enough so that that period of time is very short compared to the time of launching. That's IT.
I suggest you start with producing examples of things that operate with 99.95% efficiency.
If you had 100% efficiency of launching (i.e. nothing falls back) and you launched for 2 hours and it took an hour to shut off (with some falling back during that hour)...not too efficient. If you had a million hours of launching and one hour to shut off...VERY efficient. I suggested the HT could have 960 hours launching (40 days) and one hour of shutting off with half of the stuff that goes up in that hour falling back. That is where the 1/1920 number came from. You can call it very efficient if you like, and disagree with Brown for using the term "inefficient." Maybe you can convince him to edit that out in the next edition. But quibbling on that term is not sufficient to dismantle his HT.
Nothing in nature operates at 100% efficiency. Fine, I'll drop the references to Brown's comment on inefficiency. Faulkner's findings work better anyway. Besides aiming a stream of hypersonic material at a crumbling wall of rock is going to create a lot of splatter. Reality is sufficient to dismantle the Hydroplate model.
Actually you have already agreed I think that the launch phase WAS very efficient as far as not putting heat into the atm...so you really have no basis of quibble with what WB wrote!
My "quibble" has nothing to do with the launch phase except as a source of material that will fall back to Earth.
He claims he understands refrigeration principles...I think he doesn't. His comment about 700F water proves it. I could maybe sound convincing also if I said you can't freeze a person's hand with a can of 95F freon under pressure of 100psi by releasing it to expand and evaporate. But I would be wrong to say that.
Refrigeration works by the evaporation of a liquid. In doing so, the refrigerant absorbs energy from the surroundings. The can of 95F freon will cool because freon has a boiling temperature of around -40F. That means it will immediately boil until the surounding temperature is around -40F. What's the boiling temperature of water? There's a reason we don't cool buildings with 700F water.
Can you picture a fire hose that is shooting water in a vacuum (so there is no friction with the air) over a fence so that it is filling up a giant swimming pool, and you run that thing for 40 days and then shut it off quickly...that there might be a million times more water over the fence than what might get onto the yard in front of the fence when it is shut off? Is that a plausible scenario or not...if you rule out the friction with air?
Yes or no? Please be upstanding and give a yes or no and then explain if you want.
First, Brown's model can not involve a vacuum as it must be transferring material to space. Second: In his rocket science page he uses a velocity of sound of 0.2 mi/sec inside his chamber to calculate the velocity of the material. This is the speed of sound at one atmosphere pressure. Sound cannot travel thru a vacuum. Third, there will be friction with the air. The high velocities claimed by Brown will create a low pressure region which will suck in air from the surrounding area. Fourth: Now, use the reality of the situation and shot that fire hose over the fence for 40 days filling up that swimming pool. All the water on the ground between the hose and the pool is stuff that didn't make it. Oh yeah... no fair polishing the nozzle of the fire hose it should reflect the shape and texture of the walls this material would be hitting.