Self-fueled Radbolt Engine for Free Heat and Radiation

[ghkbrew]

 

The concept is simple. Repeatedly launch and land a radbolt engine to take advantage of the heat and radiation of the exhaust.  When taking off or landing the engine will add heat and radioactive contaminates to the chamber below the rocket.  Use the radiation produced by the rocket to fuel it and launch it again.

The wolframite airlock doors then close sequentially to compress all the hydrogen (and the radioactive contaminates it contains) into a single tile on top of the radbolt generator.

When running the rocket continously, the radbolt generator will produce ~28k radbolts per cycle while the doors are closed.

Heat is extracted with a loop of wolframite radiant pipes containing hydrogen.

Which gives a little less than 6 steam turbines worth of heat.

Or enough to heat to melt the walls of a rocket capsule a less than 4 cycles. (This was my main goal.)

The automation is unfortunately complex, but this design is completely stable as far as I can tell. 

The doors are opened and the rocket is launched when a. the rocket signals it's ready, and b. the temperature (as measured by a loop of 1kg water packets) is less than 2600C.  You have to throttle based on temperature or you'll melt even the wolframite doors and obsidian walls.

I'm using counters as rising edge detectors for the launch signal and for the return signal.  The return signal passes through an 18s pulse delay (buffer + filter) before signaling to close the doors, because the rocket platform's "ship present" output turns on as soon as the rocket enters the top of the map.  18s is just enough time for the rocket to fully land in this setup, but will need to be changed based on the rocket platform's position.

The launch signal is controlled with a memory toggle that is turned off as soon as the "rocket present" goes red, because for some reason the "ready for take-off" signal stays green until the rocket fully lands which causes premature launches if you rely on it alone.

With this, the system is completely automated as long as you have a pilot in the capsule. I'm sure life support replenishment can be automated too, but I've just been manually restocking as necessary, which can easily go as long as 50 cycles with a single dupe in a spacefarer module.

 

[asurendra]

Hm... And what are you going to do with melted rocket walls?

[ghkbrew]

2 hours ago, asurendra said:

Hm... And what are you going to do with melted rocket walls?

There's so much room for activities!

Don't you want a rocket that can hold a bedroom, bathroom,  great hall, and nature reserve for 8 dupes with life support?

[Gurgel]

Hahaha, I see the "insane engineering" spirit is alive and well!

 

[Jurij I. Gorkij]

Myself, I am fan of cramped interior of standard rockets, but i must applaud at engineer ingenuity to destroy things (walls)

[Prince Mandor]

What is material of rocket platform?

Cant it became more efficient if we add some molten metal into shaft to absorb heat of rocket one tile higher?

[ghkbrew]

10 hours ago, Prince Mandor said:

What is material of rocket platform?

I'm using lead, actually.  Rocket platforms (like all rocket components) don't interact thermally with their environment.

10 hours ago, Prince Mandor said:

Cant it became more efficient if we add some molten metal into shaft to absorb heat of rocket one tile higher?

Yeah, that should be possible.  I did play around with putting a little molten uranium on the diamond tiles.  I'm not sure how much it helped.  I should probably test it more systematically.  Part of the problem is you also want to isolate your heat brick from the exhaust because the nuclear fallout is "only" emitted at ~1300C, so once you get up to temperature you're actually losing heat to it.

[Prince Mandor]

12 hours ago, ghkbrew said:

Part of the problem is you also want to isolate your heat brick from the exhaust because the nuclear fallout is "only" emitted at ~1300C, so once you get up to temperature you're actually losing heat to it.

It is not isolated now, there are diamond plate on top of heatblock as I can see.

Do fallout emitted in liquid filled tiles? It can only be measured, i think. On your scheme, if we add two layers of metal fallout will be on space-exposured level (no backwall) and possibly dissipation will be fast enough. And two extra layers of heating will give a lot of heat.

I don't think filling up entire shaft is realistic, but by using different metals it is quite possible to make couple of layers

[cezarica]

Is there a reason for picking hydrogen instead of steam in the heat loop?

[ghkbrew]

On 6/2/2023 at 5:41 AM, Prince Mandor said:

Do fallout emitted in liquid filled tiles? It can only be measured, i think.

Yeah exhaust is emitted in liquid tiles.  You can see it when landing a rocket underwater (e.g on the water moonlet).

On 6/2/2023 at 5:41 AM, Prince Mandor said:

On your scheme, if we add two layers of metal fallout will be on space-exposured level (no backwall) and possibly dissipation will be fast enough. And two extra layers of heating will give a lot of heat.

Yeah, I think you're right.  After some testing, adding more material to absorb exhaust heat is definitely beneficial.  Even just adding some drywall, with a couple temp shift plates for thermal mass for the bottom ~5 layers gives a measurable increases in heat output.  The extra exhaust heatting makes up for the addition of the relatively cooler fallout gas.  I see no reason why a full silo wouldn't be an additional improvement, though you'd have to extracting heat from the upper portions directly, and deal with getting the pilot in and out through the dense 2600C fallout.

 

18 hours ago, cezarica said:

Is there a reason for picking hydrogen instead of steam in the heat loop?

The biggest benefit is to avoid having to worry about steam condensing in the pipes.  I'll admit I never tried using steam, but I expect you'd break a lot of pipes before the you heat the rocket walls up.

Also, I don't expect there to be much benefit.  Hydrogen is able to remove the heat as fast as it's produced even with ~half the SHC.  The temperature sensor doesn't throttle launches until after the rocket walls start melting.

Maybe if you can increase the heat output enough with technique discussed above it would be worth using steam instead.

[Prince Mandor]

6 hours ago, ghkbrew said:

Also, I don't expect there to be much benefit.  Hydrogen is able to remove the heat as fast as it's produced even with ~half the SHC.  The temperature sensor doesn't throttle launches until after the rocket walls start melting.

Maybe if you can increase the heat output enough with technique discussed above it would be worth using steam instead.

Pipes exchange heat with it's content at lowest of thermal conductivity. This means for most cases thermal conduction limited by pipe, not by gas, so no difference

[SharraShimada]

On 6/5/2023 at 9:43 AM, cezarica said:

Is there a reason for picking hydrogen instead of steam in the heat loop?

When steam cools down below (i believe) 98°C it condenses inside the pipe back to water, breaking the pipe and dripping out. A gaspipe cant contain liquids. So you would have to make absolutely sure, steam will NEVER get below 100°C at any time. Even when your rocket wont launch for any reason in time. 

[cezarica]

I think you missed the part '2600 °C' part in the original topic. As for why I asked about steam, it's because the stats steam has and was merely interested if tested to measure the benefit in using it instead of hydrogen, the downsides where obvious.

[Pedro_L]

On 6/23/2023 at 1:28 PM, cezarica said:

I think you missed the part '2600 °C' part in the original topic. As for why I asked about steam, it's because the stats steam has and was merely interested if tested to measure the benefit in using it instead of hydrogen, the downsides where obvious.

might as well use gas super coolant for max efficiency

[gerrybosvark]

On 5/26/2023 at 9:33 PM, ghkbrew said:

I'm using counters as rising edge detectors for the launch signal and for the return signal. 

For me it's not apparent how to configure the counters, your annotated screenshot mentiones 1% but when I open the counter I get one of these overviews, depending on the Advanced Mode toggle:
 

[ghkbrew]

12 hours ago, gerrybosvark said:

For me it's not apparent how to configure the counters, your annotated screenshot mentiones 1%

Yeah, it's labels aren't obvious for counters. The 1 refers to the count setting (the default is 10; change it to 1 with the arrows or by typing) the % is just the marker for advanced mode being activated.

In that mode the counter will output a 1 tick green pulse every time the input turns from red to green. Making it a compact "rising edge detector".

[gerrybosvark]

Oh and for everyone else trying rocket automation for the first time: build that automation stuff out of tungsten. My first start (rocket taking off and landing again) already melted steel automation wires and the AND gate.

[gerrybosvark]

I have another question, what liquid do you use at the radbolt generator (and especially: how much)? My first guess was nuclear waste but that just now evaporated. I probably should have guessed that thats some liquid metal.

[ghkbrew]

8 hours ago, gerrybosvark said:

I have another question, what liquid do you use at the radbolt generator (and especially: how much)? My first guess was nuclear waste but that just now evaporated. I probably should have guessed that thats some liquid metal.

It's 50kg of molten uranium, it's got a pretty incredible liquid temperature range.  I just drop 50kg of uranium ore or depleted uranium in there before I close it up.   The amount doesn't really matter so long as it's not enough to flow into the adjacent tile.  The heat from the rocket will melt it eventually. You'll get half the radbolts until it melts, but it'll still be self sustaining.