Strange, Yet Effective Big Reactors

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Someone Else 37

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This seems to be slightly more efficient. Cryotheum is very good at moderating the neutrons produced by the cores, meaning that if it's between a core and something that can interact with those neutrons (such as another core or some coolant), the other thing will do so more efficiently. Resonant ender, however, is very good at absorbing moderated radiation outright and producing heat, which can then be turned into power. So you want cryo between and surrounding your cores, and ender outside.

The middle ring of resonant ender in your design absorbs a lot of neutrons that could otherwise fertilize other cores, so replacing it with cryo and filling the corners with ender ups the efficiency to about 67.6 kRF/mB and the raw output to 122.3 kRF/t.

I've gotta wonder, though, if you're putting this much resources into a reactor, if it wouldn't be more worth your time to just install a few of Reika's mods and jump into ReactorCraft.

Side note: If BR's blutonium acted like real-life plutonium in the reactors, cryotheum between cores would be actively bad when using it, since plutonium requires unmoderated neutrons to undergo induced fission. Better to just jam all the cores together in the middle and surround it with cryo and ender in that case.
 
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rhn

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This seems to be slightly more efficient. Cryotheum is very good at moderating the neutrons produced by the cores, meaning that if it's between a core and something that can interact with those neutrons (such as another core or some coolant), the other thing will do so more efficiently. Resonant ender, however, is very good at absorbing moderated radiation outright and producing heat, which can then be turned into power. So you want cryo between and surrounding your cores, and ender outside.

The middle ring of resonant ender in your design absorbs a lot of neutrons that could otherwise fertilize other cores, so replacing it with cryo and filling the corners with ender ups the efficiency to about 67.6 kRF/mB and the raw output to 122.3 kRF/t.
Yeah, and while the pattern looks interesting, I have yet to see a case where applying some more "uniform patterns" doesn't pay off better:
http://br.sidoh.org/#reactor-design...EC15XC2ECXCXCXCXCXCXCXCXC2EC15XCE2O15C4O15E2O
That one will do up to 150 kRF/mB or up to 135kRF/t(though at a stupid high temp) depending on control rod setting.
Somewhere around 83% control rod would be where I would run it I guess. 66kRF/t, 140 kRF/mB @1200C
 

RavynousHunter

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This seems to be slightly more efficient. Cryotheum is very good at moderating the neutrons produced by the cores, meaning that if it's between a core and something that can interact with those neutrons (such as another core or some coolant), the other thing will do so more efficiently. Resonant ender, however, is very good at absorbing moderated radiation outright and producing heat, which can then be turned into power. So you want cryo between and surrounding your cores, and ender outside.

The middle ring of resonant ender in your design absorbs a lot of neutrons that could otherwise fertilize other cores, so replacing it with cryo and filling the corners with ender ups the efficiency to about 67.6 kRF/mB and the raw output to 122.3 kRF/t.

Aaah, I didn't think about that, good point and a very good thing to note for future designs. Might only bump its output up by about 1.2%, but since its output is already high, even that 1.2% translates to a good bit of power.

I've gotta wonder, though, if you're putting this much resources into a reactor, if it wouldn't be more worth your time to just install a few of Reika's mods and jump into ReactorCraft.

Aah, but if you're playing on an Infinity server, you can't do that unless you're the owner. I don't quite have the money yet to run my own server, lol. At least, not personally; my girlfriend might, but talking her into paying for a modded Infinity server when we're trying to save for a house is gonna be an uphill battle, and that's being optimistic, lol.
 

KingTriaxx

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For a given value of effective, I find a 5x5x3 reactor, full of rods to be highly effective. It burns lots of fuel, but since what I'm after is all the Cyanite I can get my hands on, that's fine.

I tend to not use reactors for Steam production. I use Railcraft Steam Boilers instead, but big turbines require a lot of Cyanite, so I use one flat large reactor.
 

Inaeo

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For a given value of effective, I find a 5x5x3 reactor, full of rods to be highly effective. It burns lots of fuel, but since what I'm after is all the Cyanite I can get my hands on, that's fine.

I tend to not use reactors for Steam production. I use Railcraft Steam Boilers instead, but big turbines require a lot of Cyanite, so I use one flat large reactor.

If all you're in the market for is cyanite, why bother building a reactor at all? Yellorium and sand makes cyanite. Now all the materials that would have been built into a purposely inefficient reactor can go straight into the turbines you came for.
 

KingTriaxx

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Can't get to my world at the moment, but I don't think that worked in Monster, and that's what I'm playing. Hence the breeder.
 

ScottulusMaximus

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If all you're in the market for is cyanite, why bother building a reactor at all? Yellorium and sand makes cyanite. Now all the materials that would have been built into a purposely inefficient reactor can go straight into the turbines you came for.

Well that's news to me... FFS that's new, and just built a nice inefficient reactor to generate me some cyanite
 

Inaeo

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I want to say it got added at the end of the 1.6 life cycle, but I have a hard time remembering what I ate for breakfast most days, so...
 

Someone Else 37

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Can anyone explain this anomaly?

http://br.sidoh.org/#reactor-design...X2C21G2C17X4C17X2C21G3C15X6C15X3C3G15C6G15C3G

I added the middle fuel rod to make it as close to 50 B/T steam (if running active cooled) as possible. Its a modified version of another design.

-JJHS

What's this anomaly you speak of? It seems OK to me...

Although, I must ask: Why bother with such a gigantic reactor if you're running it at 1% power? Do note that the "Control Rod Insertion" slider in the Controls panel is how close the reactor is to turning off completely- 0% is full power (lots of steam or RF, but low efficiency), while 100% is completely off.
 
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Efficiency, 220,655.95 RF/mB. Yellorite is one of the hardest items to come by in the modpack im using. I need big power while keeping the efficiency high. I'd love to see some other designs that match it/beat it. I'm here learning! :)

Its actually a decent amount more efficient running at 98%. (226k RF/mb) @ 193k rf/t i just dont need that much RF just yet, and by then i'll be ready for a gang of turbines cranking out 700k rf/t for .44mb/t.

The anomaly is WHY is it so efficient. Surely there has to be a better (smaller?) design

-JJHS
 

rhn

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The anomaly is WHY is it so efficient. Surely there has to be a better (smaller?) design

-JJHS
It is so efficient because it is SO immensely large. The bigger you build, the better efficiency you can obtain.

As you can see it is not particularly hard to make a efficient reactor with that size casing:
http://br.sidoh.org/#reactor-design...17XC2ECXCXCXCXCXCXCXCXCXC2EC17XCE2O17C4O17E2O

But that is not saying the biggest reactors are always the best. Choosing a reactor is always a compromise: space required(some people don't just build their reactors out on a grass field and need them to fit into a build), reactor building cost(can be quite an investment to build large reactors in certain modpacks) etc.
 

Someone Else 37

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Efficiency, 220,655.95 RF/mB. Yellorite is one of the hardest items to come by in the modpack im using. I need big power while keeping the efficiency high. I'd love to see some other designs that match it/beat it. I'm here learning! :)

Its actually a decent amount more efficient running at 98%. (226k RF/mb) @ 193k rf/t i just dont need that much RF just yet, and by then i'll be ready for a gang of turbines cranking out 700k rf/t for .44mb/t.

The anomaly is WHY is it so efficient. Surely there has to be a better (smaller?) design

-JJHS
Ah, I see. The main factor that contributes to the efficiency of a BigReactor, as I understand it, is how much the cores can interact with each other. They do this by way of neutrons- the cores produce them and spit them out in the cardinal directions, where they go on to "fertilize" other cores and make them burn more efficiently. When you've got dozens of cores packed together as in your design, they fertilize each other a whole lot, and the efficiency goes way up.

Another factor is moderation. Most of the neutrons produced by active cores are going too fast to interact with much, so they fly right out of the reactor without accomplishing much anything. You need something to slow them down so they'll actually interact with other cores and coolants. Gelid cryotheum is usually the best material to use for this, although graphite isn't far behind. The graphite you have between your rows of cores doubtlessly helps contribute to your reactor's efficiency.

A third factor is absorption. Anything you put in your reactor can and will absorb any neutrons passing through it. This can be a good thing or a bad thing- if you fill the space between your cores with Resonant Ender (which is the best neutron absorber), you'll reduce the fertilization. However, if you put it on the outside, it'll do a pretty good job of absorbing neutrons trying to escape the reactor, which is definitely a good thing- it produces heat, which means power.

Speaking of heat, it's actually both good and bad. There's two heat bars in the reactor GUI- if I remember correctly, the left bar (the core heat) is actively bad and reduces the efficiency of your reactor, which is why turning on full power reduces the efficiency. The right bar (casing heat) is good in that it gets turned into power. I'm less familiar with this aspect of BR than what I described above, but I *think* that the coolants used make the reactor shuffle core heat over to casing heat more rapidly, which boosts output and efficiency.

These three factors combined mean that the most efficient reactors usually have three qualities:
1. Lots of cores. More is almost always better, if you can afford it.
2. Cryo or graphite between the cores. Sometimes it's better to just jam in more cores, sometimes moderation helps; it depends on a number of details that I'm not even slightly familiar with.
3. Cryo surrounding the cores, with ender surrounding that. The cryotheum moderates outgoing neutrons, making it easier for the ender to catch them.

One final note: Don't reactor casings require yellorium to craft? If that's the case in your pack, you might be better off with a smaller reactor, so you still have some left over to burn after building it.
 

rhn

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Speaking of heat, it's actually both good and bad. There's two heat bars in the reactor GUI- if I remember correctly, the left bar (the core heat) is actively bad and reduces the efficiency of your reactor, which is why turning on full power reduces the efficiency. The right bar (casing heat) is good in that it gets turned into power. I'm less familiar with this aspect of BR than what I described above, but I *think* that the coolants used make the reactor shuffle core heat over to casing heat more rapidly, which boosts output and efficiency.
Well the whole "heat" misunderstanding is a common problem and the mod author does not help it when he makes a bar showing "Temperature" and then calls it "Heat".. :oops:

So before I go further I think I will just get the definitions straight:
Temperature: This is a measure of how much kinetic energy is stored in the atomic/molecular structure of something.
Heat: Measure of energy transferred from one place to another.

So a stove might have a Temperature of 800C and give off 1000W of Heat.


Back to reactors:
The Fuel rods(core) in your reactor produces energy. This energy raises the temperature of the core(The core have more kinetic energy stored in its molecules=higher temperature). Now the Core have a higher temperature than its surroundings, but nature doesn't like that so it will start evening the temperatures out by transferring energy out(Heat). The rate of transfer is depending on two things: Temperature difference and heat conductivity of the material. If you have a bad conducting material the core temperature will rise(energy builds up) until it finds a resting point where the large temperature difference makes up for the bad conductive properties.

Now in BR you have a goal of transferring heat from the Fuel rods to the "Casing" where it will be transformed into RF or steam. I put "Casing" in quotes because it is not the outer shell of the reactor. It is merely an imaginary place which the "Thermal conductive materials"(It is NOT cooling materials IMO, their function is not to cool things down but to transfer energy) transfers the heat to. So you do not need to worry about chaining the heat from the fuel rods out to the outer walls. Simply placing a conductive material against the side(s) of a Fuel rod is enough.
So in general the way to transfer as much heat from the fuel rods to the "casing" is to place as much high conductive material against the sides of the fuel rods a possible. Cryotheum is the #1 choice here.


The efficiency reduction you speak of is linked to the core Temperature. The hotter the core temperature(the fuel) gets, the more fuel does the reactor consume. It slowly raises up to around a 10% increase at around 1000C I believe, and then it really starts taking off after that! You should generally always stay below 1000-1200C IMO. Higher and you get penalized way too severely. But running your reactor too cold you also don't really get much value of your reactors initial cost/space usage.

But it is not all that simple, because AFAIK the radiation production is actually linked to the temperature of the core. So the hotter it runs the more radiation they produces to fertilise each other. Again a reason why you don't want to run your reactors too cold.



These three factors combined mean that the most efficient reactors usually have three qualities:
1. Lots of cores. More is almost always better, if you can afford it.
2. Cryo or graphite between the cores. Sometimes it's better to just jam in more cores, sometimes moderation helps; it depends on a number of details that I'm not even slightly familiar with.
3. Cryo surrounding the cores, with ender surrounding that. The cryotheum moderates outgoing neutrons, making it easier for the ender to catch them.

1. The smaller the reactor is, the more Fuel rods the better. Pack them together in a big bunch and forego conductive materials except on the outside of the clump. As the reactor slowly gets larger you need to move from clumped up fuel rods to more Cryotheum touching sides per Fuel rod simply to deal with the Temperature.
2. Generally don't bother with Graphite. It is there to serve as a decent material if you don't have TE installed. But if you have access to Cryotheum and Ender, then use those. I tend to only use it to fill up corners etc. as it is cheap.
3. The Ender "jacket" to pick up Slow radiation is on paper a good idea, but in reality it is often not worth it IMO. In smaller reactors for example it is instead more efficient to forego it and pack in more Fuel rods for example. On large reactors it might become worth it with a single layer of Ender due to diminished returns on more cores because of temperature. Sad that this mechanic was not balanced properly...
 

RavynousHunter

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Just designed one I'm dubbing the Eye of Harmony, because it gets lots of power (around 82.3k RF/t) and is very efficient (around 0.615 mB/t, 134k RF/mB). Its a big, flat reactor I made on a whim; wanted to see if an eye pattern would be efficient, if designed properly, and lo and behold, it actually is!
 

rhn

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Just designed one I'm dubbing the Eye of Harmony, because it gets lots of power (around 82.3k RF/t) and is very efficient (around 0.615 mB/t, 134k RF/mB). Its a big, flat reactor I made on a whim; wanted to see if an eye pattern would be efficient, if designed properly, and lo and behold, it actually is!
For something that large it is neither high power output nor efficient. Just took your size as template, filled it with Cryotheum and doodled something random with Fuel rods and got one that produces more power at a higher efficiency :p
 

RavynousHunter

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Snap. Though, I was more going for the general shape than anything else, lol.

[ETA]
Fiddling around with the simulator more, attempting to better my understanding of how to best build a reactor, and happened upon one that's reasonably good for its size. 21x21x3, outputs just over 100k RF/t, and has an efficiency rating of around 100k RF/mB.

From what I'm gathering, ender is good around the edge of the casing, since it absorbs more neutrons than cryotheum, preventing them from hitting the casing and increasing fuel burnup. Cryotheum is good at moderating heat and transmitting neutrons between fuel cores, allowing them to fertilize one another more efficiently. Neutrons travel 4 meters before petering out, so keeping rod groups within 4 meters of one another is good to help them interact with one another. Rods that are directly adjacent add the most fertility, but also add much more heat, so it seems best to either keep your rods going in a single (vertical or horizontal) series of lines or group them together in small, nearby clumps.

[ETA]

And another one, a variation on the one previous, that's around 2-3k RF/t better, and only increasing fuel consumption by around 0.03 mB/t.
 
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Skyqula

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Cryotheum is the #1 choice here.

Actually it isnt first place ^^ Manyullyn (Tinkers Construct) is nr one with a value of 4.5. Cryotheum takes shared third place with 3.0. Tartarite is second with a value of 4.0 (metalurgy metal I think). You can check the source code.

It is NOT cooling materials IMO, their function is not to cool things down but to transfer energy

Isnt that what alot of "cooling" systems do? Transfer heat from 1 thing to another? Like pumping water trough a motor, heat transfer to water, water moves to "cooling block" wich warms up and "cools down" trough air?

But it is not all that simple, because AFAIK the radiation production is actually linked to the temperature of the core. So the hotter it runs the more radiation they produces to fertilise each other. Again a reason why you don't want to run your reactors too cold.

I am not confinced of this at all. Each rod can store a certain amount of yellorium. Each rod produces radiation based on the amount of yellorium stored (more rods ==> less waste buildup per rod (max of 1 ingot) ==> more radiation). I like to see the "casing" as a tank. It can store heat. Heat generates RF. To much heat and the pressure rises, reducing efficiency. Infact. It explains why a huge reactor with barely anny rods in it can be so efficient. Low temperature, very low values for radiation speed (aka no fast radiation) wich means all radiation can be absorbed. Compare this 4 rods huge reactor to this 4 rod small reactor.

In most reactors temperatures of around 750 seem to be the sweat spot for efficiency. Some reactors its the point just below 1000 (the ramp up after a thousand is realy fast). This indicates that aslong as radiation can still be slowed down and absorbed everything is fine. And I do believe that radiation actually has a speed paramater that is tied to temperature. So the higher the temperature the faster the radiation and the more it needs to be moderated (slowed down) before it can generate RF. So in a sense you are right.
 

rhn

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Actually it isnt first place ^^ Manyullyn (Tinkers Construct) is nr one with a value of 4.5. Cryotheum takes shared third place with 3.0. Tartarite is second with a value of 4.0 (metalurgy metal I think). You can check the source code.



Isnt that what alot of "cooling" systems do? Transfer heat from 1 thing to another? Like pumping water trough a motor, heat transfer to water, water moves to "cooling block" wich warms up and "cools down" trough air?



I am not confinced of this at all. Each rod can store a certain amount of yellorium. Each rod produces radiation based on the amount of yellorium stored (more rods ==> less waste buildup per rod (max of 1 ingot) ==> more radiation). I like to see the "casing" as a tank. It can store heat. Heat generates RF. To much heat and the pressure rises, reducing efficiency. Infact. It explains why a huge reactor with barely anny rods in it can be so efficient. Low temperature, very low values for radiation speed (aka no fast radiation) wich means all radiation can be absorbed. Compare this 4 rods huge reactor to this 4 rod small reactor.

In most reactors temperatures of around 750 seem to be the sweat spot for efficiency. Some reactors its the point just below 1000 (the ramp up after a thousand is realy fast). This indicates that aslong as radiation can still be slowed down and absorbed everything is fine. And I do believe that radiation actually has a speed paramater that is tied to temperature. So the higher the temperature the faster the radiation and the more it needs to be moderated (slowed down) before it can generate RF. So in a sense you are right.
Nah what is fixed to the fuel amount in each fuel rod is:
  • Fixed power production. Source I know of says it is 10RF/100mB of fuel
  • Heat produced(energy that you need to transfer to the imaginary "Casing" to produce RF).
Radiation produced is dependant on core temperature. If you are in doubt then just try and adjust the control rod settings of this:
http://br.sidoh.org/#reactor-design...false&controlRodInsertion=100&layout=23O2X24O
You will see Reactivity is 100% at 100% Control rod. It then goes up as you approach 1000C and then starts going down again. This is because of radiation consists of two types:
  • Slow Radiation: This radiation can be absorbed by other Fuel rods(and absorbent materials to produce heat)
  • Fast radiation: This goes through blocks and does nothing unless moderated by certain materials, at which it becomes slow radiation.
At low temperatures you don't produce much radiation but it is primarily Slow radiation. This is why Reactivity goes up as you reach 1000C. But as higher you go the more the mixture shifts more towards Fast Radiation which simply passes through the other Fuel rod, resulting in a loss of Reactivity. So as you can see there is a sweet spot for Reactivity due to radiation somewhere around 1000C. (unless you have a lot of moderating material between fuel rods then it might be shifted upwards a bit, but no material have a very high moderation without also absorbing a little AND using up some of the 4 blocks that the radiation will spread resulting in fewer other Fuel rods being iradiated)



Isnt that what alot of "cooling" systems do? Transfer heat from 1 thing to another? Like pumping water trough a motor, heat transfer to water, water moves to "cooling block" wich warms up and "cools down" trough air?
To me a cooling material is something that removes unwanted heat. Here we are actively producing this heat to use it, we are not trying to get rid of it because it is unwanted. It is a matter of Cooling materials being Thermal conductive materials, but Thermal conductive materials not necessarily being cooling materials. Like rectangles and squares :p
 
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