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My new G250Vs and ramblings

Discussion in 'Regulators' started by buddhasummer, Dec 25, 2020.

  1. rsingler

    rsingler Scuba Instructor, Tinkerer in Brass Staff Member ScubaBoard Sponsor

    # of Dives: 500 - 999
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    Yeah, that was unfair of me to throw Poseidon under the bus. With the Venturi collar in the right position, it's a fantastic reg.
     
    Geo7 likes this.
  2. Geo7

    Geo7 Contributor

    # of Dives: 2,500 - 4,999
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    Thanks for the insightful post @rsingler! Since this thread is about venturi design, I am now wondering what the dynamic flow curve looks like for the D420 in comparison?
     
  3. rsingler

    rsingler Scuba Instructor, Tinkerer in Brass Staff Member ScubaBoard Sponsor

    # of Dives: 500 - 999
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    Frigging awesome, to be honest.
    Screen capture from a video:
    20210111_150404.jpg
    20210111_150529.jpg

    And remember, this plot is on the surface. Standard reg position in the water adds another 0.75" of pressure on the valve. Looking at those plots above, that explains why the thing is dang near effortless. From 0-4CFM (common breathing flow), inhalation resistance underwater actually becomes 0.5" to 0.05"!!!
     
    Geo7 likes this.
  4. lexvil

    lexvil ScubaBoard Sponsor ScubaBoard Sponsor

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    rsingler likes this.
  5. Geo7

    Geo7 Contributor

    # of Dives: 2,500 - 4,999
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  6. rsingler

    rsingler Scuba Instructor, Tinkerer in Brass Staff Member ScubaBoard Sponsor

    # of Dives: 500 - 999
    Location: Napa, California
    5,274
    6,695
    Well let's not derail Simon's thread much further, but if EN250 conditions at high RMV and great depth are in any way related to, say, 25+ CFM flow rates at the surface (see "Reynolds number"), then it looks like the D420 crosses gently into freeflow a bit past where I measured it. But not flagrantly.
    Screenshot_20210111-151425_Gallery.jpg
    But if this bears further discussion, how 'bout we head over to the D420 thread?
     
    buddhasummer, Geo7 and couv like this.
  7. buddhasummer

    buddhasummer Bat sh.t crazy ScubaBoard Supporter

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    My thread as run it's course. Do as you please, where ever you please. All good stuff. Cheers.
     
  8. buddhasummer

    buddhasummer Bat sh.t crazy ScubaBoard Supporter

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    PS don't get me back on the D420 please.
     
  9. Geo7

    Geo7 Contributor

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    I find it hard to resist now...
     
    buddhasummer likes this.
  10. buddhasummer

    buddhasummer Bat sh.t crazy ScubaBoard Supporter

    # of Dives: 1,000 - 2,499
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    Resistance is futile ...
     
    Geo7 likes this.

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