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The Unified Engine Raft II

#21
What is PPBB and is the higher it is the better?
"Anata no soba de! " - Hearts of Iron phrase.
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#22
Iirc, "power per bounding box". Basically how power 'dense' the engine is

(2018-07-20, 02:31 PM)Gamng19 Wrote: What is PPBB and is the higher it is the better?


Maker of moderately good: CRAM, APS, and engines.  
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#23
Yeah. PPBB is "Power Per Bounding Box." You get it by dividing the engine's power by the volume of its size-box. So a 5x5x6 engine has a volume of 150. If this hypothetical engine produces 3000 power, then you take 3000/150 to find it to have a PPBB of 20.

This volume may include air blocks. Thus, if you instead wanted to use "power per block," you would subtract the number of "air blocks" from the volume. However, unless min-maxing a small fighter or something where you will want to stuff things into every spot you can, PPBB is usually the better measure since it reflects how much power you can fit into the box-shaped room on your ship that you intend to put an engine into.

Assuming two engines to have the same efficiency, and that you don't have any size/shape restrictions, then the engine with the higher PPBB is better.
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Your giant expensive powerful warship of doom can be destroyed by dropping an anvil on it. One day, I will finally have enough engines to actually make a ship without stopping to make more engines.
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#24
I mde one that is over 9000.
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#25
Added Toaster's steam engine to the raft. Modified it a bit to spool up faster. Might also be a bit more powerful now. Stats listed are just for that 3-boiler-long version mind you, and it apparently gets stronger when made longer. I'll test that out sometime, but for now its on the raft.

Fun fact: There actually IS a use for pressure release valves.

The new enhanced toaster steam engine runs the danger of hitting 1800 RPM when extended to longer lengths and not under load. It has a pair of pressure release valves on it that you can use to circumvent this.

Even when steam pressure is well over the limit of the valve, the limit still determines how much it helps reduce the steam pressure. So by lowering the limit, the pressure will still drop a small amount.

The standard 3-segment long engine on the raft has the limits set to 1100 on each valve. If you make a longer version of the engine, you will want to reduce the limits to ensure the longer engine doesn't exceed 1800 RPM and damage itself.
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Your giant expensive powerful warship of doom can be destroyed by dropping an anvil on it. One day, I will finally have enough engines to actually make a ship without stopping to make more engines.
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#26
Which makes me consider something:

I am not exactly an expert with steam engines much, but this quirk of pressure release valves could be useful if you are trying to make a steam engine that spools up faster, by purposely making an engine that would under no load normally go over 1800 RPM. But to add a bunch of pressure release valves with appropriate settings so that it doesn't.

Granted, boiler sizes and such are of course factors too, but...
Your giant expensive powerful warship of doom can be destroyed by dropping an anvil on it. One day, I will finally have enough engines to actually make a ship without stopping to make more engines.
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#27
(2018-08-15, 08:26 PM)yKuramaFox Wrote: Which makes me consider something:

I am not exactly an expert with steam engines much, but this quirk of pressure release valves could be useful if you are trying to make a steam engine that spools up faster, by purposely making an engine that would under no load normally go over 1800 RPM.  But to add a bunch of pressure release valves with appropriate settings so that it doesn't.  

Granted, boiler sizes and such are of course factors too, but...
Aren't pressure release valves a waste of steam ,thus materials? The problem with steam engines self-destructing when not under load , can be solved in some other ways such:
1) when powering shields ( continues power draw , no spikes) , set the ACBs to turn of boilers ( when no enemy present) 20-30 seconds before you ACBs turn of the shields, thus letting the pistons consume the accumulated steam and prevent damage.
2) when powering offensive laser/LAMS ( "spiky" power draw) , either add storage cavities to them ( won't hurt offensive laser, will buff the LAMS , only downside is extra space needed). Or when:
 2.1) using small gearbox -add wheels and generators + some battery bank . The wheels really slow down the crankshaft when under power generation, the engine will not have enough time between spikes to ramp up to 1800 RPM.
2.2)using large gearbox- add more constant load so you are using nearly all power , or add more pistons , or decrease the "overclocking " of your steam production , or add steam turbines.
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#28
(2018-07-22, 02:23 AM)Greyfell Wrote: Iirc, "power per bounding box".  Basically how power 'dense' the engine is

(2018-07-20, 02:31 PM)Gamng19 Wrote: What is PPBB and is the higher it is the better?

That always felt weirdly overcomplicated to me. Why not just call it PPB, power per block?

Although, writing this... maybe PPBB ignores the empty spaces you can get inside that box? Although even then PPB might be better, considering they can be easily filled with fuel tanks/ressource storages.
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#29
PPBB lets us ignore open spaces so we don't have to go either counting them, or filling them with fuel boxes or something. So its only the words that are more complicated. We just count any air spaces as part of the engine for the sake of simplicity.

PPBB is [Power] / (X * Y * Z)

That is all. Just the power divided by the volume of the box it comes in, acting as if that box was "solid."

PPB is [Power] / ( (X * Y * Z) - [number of "air blocks," which you must manually count, and which may differ for different segments of extendable engines] )

This is really only useful in the event you have an engine that does NOT have a cross section that is at least mostly rectangular.

If you are just saying that calling it "Power Per Bounding Box" (the term itself) is complicated, then I won't argue with that. Would "power per volume" be better?


At any rate, engines tend to be overall boxy in shape, so for any ship of a size large enough to mount most of these engines what you really care about is simply the box you place the engine in. If there is some air space to stick fuel in, then that is a bonus only if you are trying to fill every single part of the ship with parts or armor (which I don't really ever see outside of the smallest vehicles).

When making a ship, you usually have some X wide and Y tall area that is Z long, where you plan to put an engine. So you are best off using PPBB to determine which X by Y extendable engine will get you the best power for that space, based on the efficiency you want. Worrying about air pockets in the engine itself won't help you for typical vehicle construction. I mean, when is the last time you actually NEEDED to stuff fuel or other blocks inside gaps of an engine? You typically would have enough room to stick some around somewhere else (the engine itself wouldn't usually actually have THAT much room anyway).
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Your giant expensive powerful warship of doom can be destroyed by dropping an anvil on it. One day, I will finally have enough engines to actually make a ship without stopping to make more engines.
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#30
I guess you're right, it's not really worth it in terms of effort. Crafts that use parallel turbo engines usually do have space left.

PPBB isn't really an issue if you know what it means; I was mostly just curious why it was used.
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