Hose Stiffness Vs valve breaking energy

[eskimo3883]

Hi,

I may be doing too much thinking but I am curious what are people's thoughts on hose stiffness. I was thinking if a hose were infinitely flexible taking a breath would constrict the hose to some degree before breaking the valve open and some inhalation effort would be lost to hose compression. A very stiff hose would be less likely to compress and hence not waste any valve breaking effort. I was thinking you want a very flexible diaphragm and some what stiff hoses. Is this something that is measurable? Do some of the really stretchy hoses exhibit a noticeable effect on breathing?

[Nemrod]

Well,it could I suppose and I think it does btt like the weakest link in a chain, a well tuned regulator will begin to flow at less pressure differential that needed to compress the hoses. I think.

Nemrod

[spectrum]

Remember that the air in the hose is at a pressure equal to the water on the outside. My point being that all of the hoses strength goes to resisting the vacuum you pull. Since the regulator will begin to deliver at about 1 inch of WC the hose, especially as a circular structure probably isn't much of a factor. End for end colapse is probably the bigger factor but that is also influenced by random motion.

Pete

[pescador775]

The accordian hose does flex somewhat with internal pressure resulting from inhalation and ejection of air from the regulator. However, the flexing is linear, not on the sidewall. The degree of flex is dependant on several factors. However, the prestretch is probably most important. This does not appear to be a subject of great concern one way or the other.

[spectrum]

The accordian hose does flex somewhat with internal pressure resulting from inhalation and ejection of air from the regulator. However, the flexing is linear, not on the sidewall. The degree of flex is dependant on several factors. However, the prestretch is probably most important. This does not appear to be a subject of great concern one way or the other.

I was thinking about that on my way to work after making my post above.

My thought is that the extra volume draw called for by the telescoping hose would not come through as a higher work of breathing but rather as a time delay in delivery. Does that make sense?

Pete

[ebj]

I agree. It don't matter! These rocket science discussions makes my pea sized brain hurt bad!!!

[eskimo3883]

Hi,

Appreciate the input. I had asked the question because of the several types of replacement hoses folks are making. I was thinking as long as the breaking force was less than the collapsing force of the accordion there would be zero effect but I have no experience with the "super stretch" replacement hoses and the like.