Think your weekend of diving sucks / Read this!

[cobaltblue]

I keep my boat about 10 miles north of this intake and have dove the "bubbler" many times. The intake she got sucked through was part of a cooling system used for the huge power plant that's in Port Sheldon. The intake is on the lake side of five (I think) large discharges that make for interesting diving, they also help keept the water temp up. It's in around 45 feet of water where as the first out flow, bubbler, is in 25 feet. Alot of us didn't know all the facts of the hole, it hasn't been grated for along time, that was out in deeper water. As of yesterday, Wednesday, Consumers Energy was installing a grate on the intake.

Along with all the other comments, remember that anytime water goes through a tube like this, there is a vortex that's created. So not only was she cruising through the dark, about every six seconds she was bouncing off the tube. She was trained at the dive shop I was and some kudos go to the folks that trained her since she kept her wits about her and lived through this ordeal.

Lastly, there is no pump. There is a gate/dam that opens when the cooling ponds get low and then gravity takes over.

 

[Kriterian]

Ouch! That would be like manslaughter if you ask me. I mean, knowing that people might get sucked into your intake pipe and making sure that they have no way to get out?!

Yeah that's kind of scary, like a Diver Trap. Something out of James Bond.

 

[jcm996]

Good thing the pipe doesn't change size and was large enough to let a tank go through sideways, cause you know she had to try to filp once or twice.

At least I'm not looking for used wet/dry suits, I would be leery of buying one from Michigan right now because I know mine would have been soild pretty good by 2 minutes.

What do you think when this happens? Do you try to fight the current or grab your spare light and swim with it hopeing to get out quickly. I could see draining a full 80cf tank in less than 7 minutes under that kind of stress.

 

[CBulla]

Now... if only we could market this ride at say... Wet & Wild!

She is definitely a lucky woman!

 

[glbirch]

Sounds like something that Disney would bill as an 'E' ticket ride. Bet you could make a fortune if you had a way to get people out at the other end without being caught...

 

[simbrooks]

Along with all the other comments, remember that anytime water goes through a tube like this, there is a vortex that's created. So not only was she cruising through the dark, about every six seconds she was bouncing off the tube. She was trained at the dive shop I was and some kudos go to the folks that trained her since she kept her wits about her and lived through this ordeal.

Early into the tube or at a change in the tube (there might have been a few bends, probably not any orifices) it would have been turbulent, but after a pretty short time the flow would have become laminar (linear) and so she wouldnt have moved around much if at all in the "water column", its how pipes flow when they are relatively long, now the question is does a largish object floating inside the pipe create a field of turbulence around it or just get carried along with the water in a particle like sense? I think that it would most likely be the laminar sense. Also this pipe sounds pretty large (did i see 8ft diameter earlier?) so plenty of room in there for her to get lost in the flow and not make as much impact on the flow pattern as might happen in a smaller pipe.

Now this has me interested... wouldn't there be a bit of a Bernoulli effect going on inside the pipe? As water flows into the pipe (from the same depth as the pipe, for the sake of argument), the surrounding water, as it moves closer and closer to the pipe inlet, is forced into a narrower channel (but not compressed of course)... As such, according to Bernoulli, the water picks up speed and, thus, there would be small pressure increase just outside the pipe and a corresponding small pressure decrease when inside the pipe...

Bernouli - Total energy head is pressure related, velocity related and elevation (total head = pressure/(density*gravity)+(velocity^2/(2*gravity)+elevation) and if you are comparing to points (ie near the entrance and exit of a pipe) you can also add on a frictional loss in head which would be the difference between the two total heads.

 

[DiveGolfSki]

Looking at this, if it was a gravity system or even pumped in some way, ....

This is interesting. If she was sucked into this pipe with a significant enough force that she couldn't escape, wouldn't this imply that it wasn't a gravity system? If it were a pump or turbine system, how did she survive? Can someone be sucked into a turbine without hitting any of the blades? Maybe, I'm confused how the suction is created but does anyone have any information on this?

 

[simbrooks]

This is interesting. If she was sucked into this pipe with a significant enough force that she couldn't escape, wouldn't this imply that it wasn't a gravity system? If it were a pump or turbine system, how did she survive? Can someone be sucked into a turbine without hitting any of the blades? Maybe, I'm confused how the suction is created but does anyone have any information on this?

It was an OR statement. Pump OR gravity, mutually exclusive.

She would have been diced in a short time if there would have been a turbine IMO. There is a pressure difference between the turbine and the area being sucked from, however the pump adds energy back into the hydraulic system (transfering that energy from another place - electricity most likely) and therefore increases the head again the flow in has to equal the flow out and the energy head will be split into pressure, velocity, and elevation components and frictional losses.

 

[cmalinowski]

This is interesting. If she was sucked into this pipe with a significant enough force that she couldn't escape, wouldn't this imply that it wasn't a gravity system? If it were a pump or turbine system, how did she survive? Can someone be sucked into a turbine without hitting any of the blades? Maybe, I'm confused how the suction is created but does anyone have any information on this?

Yea, I guess if you have the pond at around sea level when no pumping is needed, that the system pumps from the pond when necessary. Then, as the pump draws the water level down in the pond, it pull in the water from the sea to "recover". I used to have a similar system with a fish tank.

Just my thoughts of course.

 

[DiveGolfSki]

Yea, I guess if you have the pond at around sea level when no pumping is needed, that the system pumps from the pond when necessary. Then, as the pump draws the water level down in the pond, it pull in the water from the sea to "recover". I used to have a similar system with a fish tank.

Just my thoughts of course.

Thanks ... I'm not well versed in hydro mechanics. Either way, she was lucky.