Waste Water seems to stay low. | Reentry - A Space Flight Simulator | Page 1

jovial dawn Mar 20, 2023, 10:29 PM

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During Flight the waste water tank seems to just drain slowly to a point near 0 and stay there afterwards. I can't see an immediate cause, as the switches seem to be in the right state, though maybe I'm missing the obvious.

lost hill Mar 20, 2023, 10:33 PM

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Hmm in that configuration it will fill from the excess fuel cell water and water accumulated from the cabin/suit atmosphere and only dump when it exceeds a given pressure (pressure relief)

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So that should be correct

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I dont know what rate its producing water in the sim right now though, but also that water is used in the glycol evaporators so if those are running they are consuming water as well

jovial dawn Mar 20, 2023, 10:34 PM

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The glycol evaps, would that be panel 2?

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It'd be panel 2 and 382 i believe, though the cooling still somewhat confuses me

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lost hill Mar 20, 2023, 10:39 PM

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jovial dawn The glycol evaps, would that be panel 2?

Yeah the remotes are on Panel 2 (switches) and the valves are in 382

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I know not related but I would be happy to clear up cooling

jovial dawn Mar 20, 2023, 10:40 PM

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yeah that'd be nice lol, and if you got time the whole rtcc but one step at a time probably 🙂

lost hill Mar 20, 2023, 10:40 PM

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Well i can explain the real RTCC not so much Reentrys 😛

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So doesnt really apply

jovial dawn Mar 20, 2023, 10:41 PM

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Well I was referring to NASSP, sends my head in spins trying to get the hang of it

lost hill Mar 20, 2023, 10:41 PM

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Ohh haha yeah that one we have a few manuals on, but its not something you explain all of it at once, its more of a try this try that learn as you go but that I could do as well

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But in a nut shell the CSM has cooling by pumping glycol through heat exchangers and cold plates, and the heat in the glycol is rejected to space by using the radiators on the SM and/or 2 water evaporators in the CM

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the primary evaporator is usually used to supplement heat loading, and on some missions it was used before larger system loads (like LOI)

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But it had a temperature mix that it would kick on and help the radiators if temps got too high as well

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but to work, it uses water from the waste tank

jovial dawn Mar 20, 2023, 10:44 PM

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so would the primary evaporator take heat from the glycol loop or directly from the instruments via plates etc

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?

lost hill Mar 20, 2023, 10:44 PM

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a picture might help, one sec

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haha damn its big

jovial dawn Mar 20, 2023, 10:45 PM

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yeah, i tried reading the AOH and the reentry manual, but the IRL astronauts had classroom experience iirc so they had an up on that one 🙂

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if u give me the link i can open the page itself

lost hill Mar 20, 2023, 10:46 PM

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http://www.ibiblio.org/apollo/Documents/HSI-481260.pdf

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pdf pg 52

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primary cooling schematic

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but the evaporator would reject heat from the glycol loop

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the glycol in the loop is what takes the heat from the plates

jovial dawn Mar 20, 2023, 10:47 PM

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pg 52 on the pdf indicator right, the one that is sideways?

lost hill Mar 20, 2023, 10:47 PM

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yes

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its a big foldout

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says PRI COOL in the bottom corner

jovial dawn Mar 20, 2023, 10:48 PM

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yeah, dwg NO 4.3?

lost hill Mar 20, 2023, 10:48 PM

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yeah

jovial dawn Mar 20, 2023, 10:49 PM

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kk seeing it, and head spinning again lol

lost hill Mar 20, 2023, 10:49 PM

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haha

jovial dawn Mar 20, 2023, 10:49 PM

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so the glycol would take heat from the plates and instruments, and the water evaporator would take heat from the glycol itself in high load situations?

lost hill Mar 20, 2023, 10:50 PM

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yep

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and if the evaporators werent running the glycol would just pass through to the radiators

jovial dawn Mar 20, 2023, 10:50 PM

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and where would the water evaporate to? cause obviously it cant just vent into the CM atmosphere

lost hill Mar 20, 2023, 10:50 PM

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Look at G8

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see the evaporator there?

jovial dawn Mar 20, 2023, 10:51 PM

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yeah

lost hill Mar 20, 2023, 10:51 PM

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Follow the duct with a bunch of "S" in it, thats the steam duct and it goes to the overboard vent

jovial dawn Mar 20, 2023, 10:52 PM

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oh ok, so it takes heat by evaporating and then gets vented overboard with the steam flow, doesn't that technically mean that the spacecraft can cool fine as long as it doesnt hit high load cooling (without the waste water I mean)

lost hill Mar 20, 2023, 10:53 PM

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so the evaporator basically adds water to a plate and it forms an ice layer which is evaporated off by the vacuum of space but of course this takes heat with it and that heat is pulled from the glycol passing through it

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Yeah normally the radiators are enough

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Though when you jettison the SM, your evaporators are your only cooling, and also during launch, the rads are bypassed (aerodynamic heating would make them useless to cool the glycol) so once you are high enough your evaporators will start working

jovial dawn Mar 20, 2023, 10:56 PM

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I also note that on D2 the primary suit heat exchanger can either be bypassed or normal, I assume bypass is when the astronauts aren't wearing the suit?

lost hill Mar 20, 2023, 11:13 PM

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jovial dawn I also note that on D2 the primary suit heat exchanger can either be bypassed or...

Yeah theres a valve on 382 thats also controlled by a switch on MDC2

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And you would actually leave it in normal even unsuited

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bypass is if the glycol is getting too cold or too hot or some other issue arises

jovial dawn Mar 20, 2023, 11:14 PM

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ohh, the more you learn 🙂

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would having the secondary glycol loop active prevent the waste water tank from increasing in quantity?

lost hill Mar 20, 2023, 11:16 PM

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in reality it would be a function of the glycol temperature, but it would use water from the tank

jovial dawn Mar 20, 2023, 11:17 PM

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but only if the glycol temperature exceeded the setting for auto, or if you manually used the steam pressure system on panel 2?

lost hill Mar 20, 2023, 11:18 PM

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yep

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but conversely if the glycol isnt hot enough you would just get a block of ice and no steam

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and of course no more water would flow haha

jovial dawn Mar 20, 2023, 11:19 PM

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wouldn't the vacuum cause sublimation to occur anyways?

lost hill Mar 20, 2023, 11:19 PM

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still need some energy to maintain it

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and yeah some surface sublimation would happen

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but the rate of water coming in would start building a larger ice layer

jovial dawn Mar 20, 2023, 11:20 PM

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if that happened i guess best thing would be put glycol on bypass and turn the water flow to manual and off

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so the ice can be vented away

lost hill Mar 20, 2023, 11:21 PM

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assuming you didnt damage it from expansion, yeah you would perform a "dryout" procedure

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basically shutting off water flow and letting warm glycol into it

jovial dawn Mar 20, 2023, 11:22 PM

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hey application is a sign of knowledge 🙂 so im learning

lost hill Mar 20, 2023, 11:22 PM

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LM did a dryout after powerups and power downs (ie Apollo 9)

jovial dawn Mar 20, 2023, 11:23 PM

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yeah that makes sense

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but i guess going back to the original issue, is there a way to get the waste water directly from the fuel cell perhaps, cause if it isnt building up even with normal potable water and water taken from the atmosphere, well whilst it probably wont have an issue till entry it bugs me lol

lost hill Mar 20, 2023, 11:24 PM

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not really

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Check out the next page of the handbook for the water layout 😉

jovial dawn Mar 20, 2023, 11:26 PM

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well i tried setting the pressure relief valve to off in case that was causing issues but even with potable water tank at full the waste water tank just sits there not increasing

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even 40 hours into the mission

lost hill Mar 20, 2023, 11:26 PM

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tells me its not implemented or not implemented correctly yet

jovial dawn Mar 20, 2023, 11:27 PM

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yeah cause with the press relief valve off and the inlet on auto it should start building up right?

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cause im just coasting so my heating load shouldnt be anywhere near high enough to cause problems

lost hill Mar 20, 2023, 11:28 PM

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pressure relief on 2 should be fine

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and waste tank inlet on auto, yes

jovial dawn Mar 20, 2023, 11:29 PM

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whats the waste tank servicing inlet for?

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if u dont mind my asking?

lost hill Mar 20, 2023, 11:30 PM

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not at all

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it allows things like disinfecting it with chlorine or drawing water from it

jovial dawn Mar 20, 2023, 11:32 PM

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oh so the water can be drained from the waste water tank into the waste servicing tank? and does the waste servicing tank release chlorine into the waste water tank or just has its own set of chlorine?

lost hill Mar 20, 2023, 11:32 PM

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well its not a waste servicing tank, its a fitting that attaches to allow a connection

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its to "service the waste tank" not a waste servicing tank

jovial dawn Mar 20, 2023, 11:33 PM

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oh.. yeah order is important in english, my bad

lost hill Mar 20, 2023, 11:33 PM

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haha

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It was also used if water needed to be dumped though the side hatch instead of the CM nozzle

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this was done for experiments, as well as a contingency for if the dump nozzle on the hull froze

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the chlorination was a bad example as that was usually done to the potable tank, but it could be done to the waste

jovial dawn Mar 20, 2023, 11:35 PM

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oh so they connect the chlorine to the waste tank servicing and put chlorine into the waste water tank?

lost hill Mar 20, 2023, 11:35 PM

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could be done, but I am pretty sure it was never done to the waste tank

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this was the method for the potable tank though

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not this port but a similar one

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it had an injection port

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with a special fitting

jovial dawn Mar 20, 2023, 11:36 PM

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oh, so could u irl take water out of the potable water and manually inject into the waste water tank?

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im just trying to think of a way to get this waste water tank level a bit higher than 40% and slowly draining

lost hill Mar 20, 2023, 11:41 PM

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Again I dont think its implemented correctly or at all in Reentry

jovial dawn Mar 20, 2023, 11:41 PM

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i know its implemented cause the last flight, it worked ok for about 60% of the mission

lost hill Mar 20, 2023, 11:41 PM

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then probably not correctly haha

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@kindred finch could answer that

jovial dawn Mar 20, 2023, 11:42 PM

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yeah, fair, so final few questions? I know ive taken ur time

lost hill Mar 20, 2023, 11:42 PM

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Oh I dont mind at all

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I enjoy this stuff

jovial dawn Mar 20, 2023, 11:46 PM

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so, im still mildly curious could you manually put water into the waste water tank with the waste water tank servicing, but the 2 big questions I had to mind are.

If you put pressure relief to off all that does is turn off the automatic pressure relief for the water right, it doesn't do anything else besides.
If the waste water tank servicing is open, you'd have to put a hose into it for it to drain right? It wouldn't just automatically flow out. (stupid question i know)
The potable and waste water tank inlets when put in the open/auto allow water to flow in right to their respective tank? I'm pretty certain they do, but I've seen some tricks in aviation occasionally about switches like that

lost hill Mar 20, 2023, 11:49 PM

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so, im still mildly curious could you manually put water into the waste water tank with the waste water tank servicing
Probably not because of the pressure in the tank, the water tanks were pressurized using bladders and pressure regulators

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If you put pressure relief to off all that does is turn off the automatic pressure relief for the water right, it doesn't do anything else besides.
Yep thats all it does

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If the waste water tank servicing is open, you'd have to put a hose into it for it to drain right? It wouldn't just automatically flow out. (stupid question i know)
Correct it needs a fitting, kind of like a quick disconnect

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The potable and waste water tank inlets when put in the open/auto allow water to flow in right to their respective tank? I'm pretty certain they do, but I've seen some tricks in aviation occasionally about switches like that
Correct

jovial dawn Mar 20, 2023, 11:52 PM

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lost hill > so, im still mildly curious could you manually put water into the waste water ...

I know i said final but this raises another question lol, if the pressure from the bladder would prevent putting water into the tank, how did they put chlorine in?

lost hill Mar 20, 2023, 11:53 PM

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jovial dawn I know i said final but this raises another question lol, if the pressure from t...

Look at the above image, you can see there is a check valve

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jovial dawn Mar 20, 2023, 11:55 PM

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oh i thought they could put chlorine via the waste water tank servicing into the waste water tank directly, you meant they put it into the waste water tank via the potable water tank

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i think? 🙂

lost hill Mar 20, 2023, 11:56 PM

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Yeah thats why I was saying I misspoke about injecting via the servicing port

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chlorine injected into the potable could also end up in waste as well

jovial dawn Mar 20, 2023, 11:57 PM

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yeah now i get ya :), thanks a lot for this learned a bit about it now, so maybe ill understand it more when reading the AOH again

lost hill Mar 20, 2023, 11:58 PM

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haha the AOH and systems handbooks are great

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I can spend a lot of time in the systems handbook schematics

jovial dawn Mar 20, 2023, 11:58 PM

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they're a bit rough if you've never read them before, though maybe that just me?

lost hill Mar 20, 2023, 11:59 PM

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oh yeah

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I have been for a few years now so I kind of know where to look for things

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like all this afternoon I was chasing down ASA heaters in the LM to fix my earlier implementation for NASSP

jovial dawn Mar 21, 2023, 12:00 AM

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christ, you guys really do like making NASA level accuracy simulators 🙂

lost hill Mar 21, 2023, 12:00 AM

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helped to know where to look lol

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yeah we do

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we are all pretty passionate even about little details

jovial dawn Mar 21, 2023, 12:02 AM

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well thanks again for all this, so I can safely say the waste water tank is just a bug and not anything I'm screwing up. So yay for that 🙂

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have a good day

lost hill Mar 21, 2023, 12:04 AM

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Haha hopefully Petri can give insight

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Feel free to drop me a ping or dm if you have other questions I can try to answer them

unkempt trout Mar 21, 2023, 8:37 PM

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@lost hill Not entirely related but… where do you read the quantity of the water tanks in the first place? I can’t seem to find the gauge

lost hill Mar 21, 2023, 8:38 PM

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unkempt trout <@270351744096141312> Not entirely related but… where do you read the quantity o...

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The gauge I circled displays potable or waste quantity depending on the switch position

unkempt trout Mar 21, 2023, 8:47 PM

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Ah OK! I took "Accum Prim/Sec" and "H20" to be part of the same gauge label, meaning I thought one side was primary and one secondary. My mistake

lost hill Mar 21, 2023, 8:49 PM

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Another case of multi use displays!

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The Accum Prim/Sec displays the primary or secondary glycol accumulator based on this rotary switch

unkempt trout Mar 21, 2023, 8:50 PM

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Ok

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The problem with this specific case is that the formatting of the label in Reentry reads as "Accum Prim/Sec H20", not "Accum Prim/Sec H20" like in the diagram you posted.

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So it looks like one label

lost hill Mar 21, 2023, 8:52 PM

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Oh really?

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Yeah this is CSM 114's panel schematic

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So it should match J mission panels

unkempt trout Mar 21, 2023, 8:53 PM

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Is that... Apollo 13?

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No, it's not

lost hill Mar 21, 2023, 8:53 PM

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17

unkempt trout Mar 21, 2023, 8:53 PM

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Ok

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A shot of the MDC-2 gauges

lost hill Mar 21, 2023, 8:56 PM

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yeah thats not quite right

lost hill Mar 22, 2023, 1:22 PM

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Graphics bug @kindred finch ☝️ "H2O" is too far to the left

unkempt trout Mar 22, 2023, 8:19 PM

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I think the font is just too big to allow for the realistic spacing. Also, there appears to be a bolt missing just to the right of H20 from Folger's schematic.

lost hill Mar 22, 2023, 8:41 PM

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Yeah I noticed the missing screw head also

#Waste Water seems to stay low.