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jaap · 13th May 2008, 18:06

Quote: (Originally Posted by se2schul)

Can anyone help me out with the algorithm used to calculate the loop stabilization on the RB80?

I'm also interested in how to calculate when the loop will go hypoxic during a depth change.

I am trained on the RB80, and I'm aware of the "rules" to follow to avoid hypoxia while diving the unit.
I'm also aware of a battlefield calculation to calculate at approximately what depth a gas becomes hypoxic.
I also have some simulation software that is supposed to calculate these things for me, however, the software is half German - half English, the interface is a bit "clunky", and I'm not always sure what it's doing. I'm not sure if there's a newer version of this software available.

Anyway, if anyone can help me with the loop stabilization algorithm, and the hypoxia algorithm, it would be much appreciated.

Hi

Have you studied this page:
Le Spirotechnique DC55

Since I got an old HAL-fridge collecting dust (yes I know its a different thing with the variable dumpratio) I did an Excel sheet some years ago that calculates the steady state loop fractions for a given feedgas, depth, dumpratio and extraction ratio. Its partially in Swedish and is based on the equations decribed on Åkes "Teknosofen" Larssons homepage. I make no claim that it is correct but you can have it if you want. But I guess that sort of stuff should have been covered in you RB80 training?

But your after time constants too right? Like in this link (but for PSCR and not CMF-SCR):
Åkes’ Constant Massflow Rebreather Technical Page

If you want to look at the time to reach steady state after a sudden movement between two steady state levels it should be quite straight forward to simulate on a PSCR too using the equations from "Teknosofen".
I really should get back to working so I hope I don't start looking at describing that one...

13th May 2008, 18:06	#3 (permalink)
jaap Normal people worry me Current Rebreather/s: Classic Kiss Other CCR RB80 / Clone Ray Other SCR Home Build Other Rebreather/s: Other CCR RB80 / Clone Ray Other SCR Home Build Join Date: Jun 2005 Location: Stockholm Sweden Posts: 451	Re: RB80 Math ? Quote: (Originally Posted by se2schul) Can anyone help me out with the algorithm used to calculate the loop stabilization on the RB80? I'm also interested in how to calculate when the loop will go hypoxic during a depth change. I am trained on the RB80, and I'm aware of the "rules" to follow to avoid hypoxia while diving the unit. I'm also aware of a battlefield calculation to calculate at approximately what depth a gas becomes hypoxic. I also have some simulation software that is supposed to calculate these things for me, however, the software is half German - half English, the interface is a bit "clunky", and I'm not always sure what it's doing. I'm not sure if there's a newer version of this software available. Anyway, if anyone can help me with the loop stabilization algorithm, and the hypoxia algorithm, it would be much appreciated. Hi Have you studied this page: Le Spirotechnique DC55 Since I got an old HAL-fridge collecting dust (yes I know its a different thing with the variable dumpratio) I did an Excel sheet some years ago that calculates the steady state loop fractions for a given feedgas, depth, dumpratio and extraction ratio. Its partially in Swedish and is based on the equations decribed on Åkes "Teknosofen" Larssons homepage. I make no claim that it is correct but you can have it if you want. But I guess that sort of stuff should have been covered in you RB80 training? But your after time constants too right? Like in this link (but for PSCR and not CMF-SCR): Åkes’ Constant Massflow Rebreather Technical Page If you want to look at the time to reach steady state after a sudden movement between two steady state levels it should be quite straight forward to simulate on a PSCR too using the equations from "Teknosofen". I really should get back to working so I hope I don't start looking at describing that one... __________________ My initials: JAAP Last edited by jaap : 13th May 2008 at 18:11.
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