Think your weekend of diving sucks / Read this!

[SueMermaid]

Wow,
and I thought having my brother lock me in the dryer for 30 seconds, and turning it on when I was a kid, was a bad ride. :11:

I can't even imagine.

That does it. I am not having kids.

 

[ygthad]

Another accident you would think should have never happen. Glad she is doing well.

 

[mxracer19]

I'd venture to say that she wasnt sucked through a pump. The holding lake probably acts as a balance for the incoming water, where the water is pumped from the holding lake into the plant, and it just flows from lake michigan through this pipe into the holding lake by the slight difference in levels. The holding lake is probably used to monitor and generally regulate the level of water that the pumps downline recieve, as well as act as a break for surge and damper excess flow. Engineers probably designed this pipe to be as straight as possible to minimize flow restrictions. Mussle growth might very well be lessened further into the pipe due to a lack of sunlight and such ample current.

but man that must have been some scary **** not knowing if there was a tubine down the tube and wondering when you were going to die for 7 minutes...and then being spit out into a manmade lake and not knowing where the next hazard or pipe intake is...Ill give her some credit.


-Matt

 

[FreeFloat]

I don't know what's worse, tumbling through the darkness, or the thought of arriving at the source of the suction. I can't imagine this being a gravity fed system, so on the face of it, she appears to have been sucked through a pump pf some sort. And then to further the thought, anyone who has dove in Lake Michigan knows of the hazard of zebra mussells. Most intake pipes are covered with them; a major problem. So, picture being tumbled down a dark, razor lined tunnel and eventually arriving at a giant blender. Now, get out of the pond with only a bloody nose. Needless to say, I'm very, very impressed.

As am I! :11:

 

[Randy43068]

I think she demonstrated skills beyond the requirements of AOW and Master Diver and should be automaticly upgraded to both levels of higher certification.

On the other hand, she was a national threat to our country by breaching the security of a power plant. Therefor she should have been arrested, interrogated, all her assets seized, and locked up in prison with the talaban. And her dive buddy should also be arrested for being a co-conspirator.

PADI has a tunnel/pipe diver cert for $150.00.

 

[medical1]

Yes but remember you must have the PADI tunnel/pipe diver cert before you can even think about the PADI tunnel/pipe "penetration" course. Thats an advanced specialty course

PADI has a tunnel/pipe diver cert for $150.00.

 

[Randy43068]

Yes but remember you must have the PADI tunnel/pipe diver cert before you can even think about the PADI tunnel/pipe "penetration" course. Thats an advanced specialty course

You're right. I forgot about that. I think the book is something like $65.00 USD also.

 

[netmage]

Ok - another aspect I'm wondering about. Essentially this diver was sucked 2500ft in 7 minutes, any idea how her depth changed over that distance? We hear stories all the time of moorings breaking and folks with deco lines getting yanked to the surface.

The article mentions a bloody nose - wondering if she was exposed to any barotrauma due to rapid ascept.

 

[simbrooks]

Ok - another aspect I'm wondering about. Essentially this diver was sucked 2500ft in 7 minutes, any idea how her depth changed over that distance? We hear stories all the time of moorings breaking and folks with deco lines getting yanked to the surface.

The article mentions a bloody nose - wondering if she was exposed to any barotrauma due to rapid ascept.

Looking at this, if it was a gravity system or even pumped in some way, the head from the entrance to the exit would gradually drop from that of the entry to that of the exit (that is how water flows, from high to low). There are 3 aspects to total energy head, static/pressure (depth/pressure based), dynamic (velocity based) and elevation, for water to flow total head must decrease by one or more of those changing - with a pump energy would be transfered to the water and energy/total head would increase increasing the pressure, but if she had gone through a pump they most likely would have found pieces of this lady rather than her whole. Velocity cant change inside a fixed diameter pipe as the mass continuity equation has to continue flow in=flow out and flow=velocity x area, so velocity cant change unless the diameter changes. Most energy is lost due to friction against the pipe walls and by any obstructions/curves etc, so that would support that even in a horizontal pipe the pressure must be the reducing factor as head drops across the system. Although elevation can change, we arent to know for sure what difference that might be and it wouldnt be related to the head losses from friction.

Inside a closed pipe (ie no air pressure affect things), flowing under gravity, the head drop (ft/ft) would be equal all the way along the pipe as its mostly dependant on friction (assuming same material throughout). She could have gone over the top of a small siphon with no issue as well. In an open channel that might be more of a concern as you can have more or less static head as your slope gradient changes, alters your velocity and elevation greatly, but this is something else altogether.

This is a rough paraphrase of hydraulic theory as best i can recall and know it.

I think the bloody nose and possibly any bumps/bruises might have been from the pipewall.

 

[ranger979]

I would think that the entire time she was inside the pipe that the pressure would remain constant at the pressure of the depth she was at. However, once she left the pipe she would go to the pressure of the surrounding area.

The story doesn't state what depth she was at when she was sucked up or whether the pipe empties out into the air or underwater in the holding pond but I would assume that there would definitely be a risk of barotrauma.