Pressure in the penis

Fibrosis is a proliferation of fibrin and collagen not unlike scarring. Priapism causes it by inducing hypoxia in the CCs. Read all about it here. Because hypoxia causes the problem, maintaining good circulation is an important part of any safe PE exercise.

Thanks, MM. Ensure good circulation, no hypoxia, no fibrosis. I should be OK then. That’s a relief!:)

If you have your book handy mbuc, what is the stress in a sphere. I remember doing this calculation once and I think it could be used to understand the pressure at the distal ends of the corpora. It could also perhaps be applied at the local curvature that is present during a jelq or clamp. I am guessings its 4 times the axial.

a true PE’er :lisa2:

Yeah book’s handy tube.

In a thin walled sphere the symmetry means the circumferential stress is equal in any direction and is calculated as being pr/2t, where p is the internal pressure, r is the radius of the sphere and t is the thickness of the sphere wall.

There is no axial stress in a sphere like there is in a tube, tube.

Where you stick a hemi-sphere onto the end of a tube the stresses in the end hemi-sphere maybe a little more complex. I shall read my book a little more!

Interesting. This seems to suggest that the stresses at the curved surfaces are reduced rather than increeased like I had thought. In addition, the radius is also decreased at the point of clamping which further reduces the stress. The maximum stresses are at the widest purely cylindrical portions. I do say, this is really stressing me. ;)

The magnitude of the stress in the cylindrical section remains constant up to the

cylinder–hemisphere juncture, where the stress magnitude tapers down to half (with slight overshoot) and

remains so in the hemispherical bulkhead region (eqs. (4) and (5)). Because of the sharp transitions in the

tangential stress and radial displacement in the cylinder–hemisphere junctures, high transverse shear stress

could be generated there. The four node elements used in the two finite element models can not provide

the transverse shear stress for which eight node elements are required.

Yep, I just started pumping and am very cautious. 3 is hardly anything, but the penis is larger than normal. 5 is on the edge of becoming painful. I keep it around 4 to 5 for about 5 to 10 minutes. So, I would have to say that my penis is in full agreement with your stats.

Mbuc,

Another engineering question for you:

I was observing my own unit as it was manhandled in the Orange Bend fashion earlier today. When I do an Orange bend, sideways to the right, for instance, the outer (left) side of the shaft curves over to the right. The right side of the shaft is compressed, so the outer tunica is not engaged on the right side, and on the left side it is simply bent, and I can push the head towards the base to keep it from being fully stretched. But the blood in the shaft needs to go somewhere, so the two corpora bulge out circumferentially around the bend.

…and here is my question:

Since I have taken the outer tunica out of action, the pressure hits the inner tunica only (the one limiting the girth). If I had the outer tunica fully active, the pressure would disperse in two directions, meaning that the force on the fibres would be half, correct? OR, by taking the outer tunica out of action, I’ve got double the force on the inner tunica as compared to the same pressure if I had both tunica active, correct?

My thinking is that when doing a Horse440 this is exactly what you are doing; only an Orange Bend is done in a more gradual and controlled fashion. But both exercises take the outer tunica out of action and forces the inner tunica to deal with the full pressure.

Am I right or just confused?

I must admit it is confusing. I think in dynamic excercises the internal pressures and stresses become much harder to understand.

I have only really considered static situations (hanging, clamping, pumping) where the pressures have plenty of time to equalise throughout the internal structures.

In the type of excercises you are considering there is localised pressure and force because it requires a finite time for the pressures to equalise by blood flowing from one place to another. I think I’m as confused as you as to how to analyse what happens in a dynamic situation.

Sorry I can’t be more helpful.:(

Well, when I do Orange bends I hold for 10-15 seconds, so the internal pressures certainly should be able to equalize. Let’s just pretend it is a static situation if that makes you feel better!

My main question is what happens when you have two layers at 90-angles and remove the one out of the equation? The pressure is the same, but does that mean that the force is double on what is left? I am thinking it should be, or maybe the force/area is a more correct way of expressing it. The area taking up the force is halved, so the stress should increase right?

I studied building technology years ago, but I don’t use any math on a daily basis since a long time ago…

I know this is an old post, but I think you m brothers are freaking hilarious. Plus I think the PE community you use a little reminder of your insight. I’m actually taking a fluids class next semester so maybe I’ll be able to help with some dynamic fluid models. Nice discussion guys.

Thanks, and I’m looking forward to all the input during next semester.

Any feedback on the two-layer theory? I keep returning to mull it over, but I can’t find any serious flaws. Nor has anyone pointed to any.

mbuc: Did you see this article?

http://www.ncbi .nlm.nih.gov/en … 4&dopt=Abstract