Has anyone tried...

Nick · Post by **Nick** » Tue Jan 11, 2005 5:06 pm

rounding out the draght hole in the bowl?

I've heard one pipe maker tried it for a bit, but discontinued doing so.

achduliebe · Post by **achduliebe** » Tue Jan 11, 2005 5:16 pm

Hey Nick,

I am not exactly sure I understand what you are talking about.

I have only made two pipes...so I am pretty sure I have not done what you are talking about, but would be interested to learn more.

jeff · Post by **jeff** » Wed Jan 12, 2005 1:27 am

Do you mean rounding the sharp edges around the draught hole as it enters the tobacco chamber? If so, I know that that is typically only employed in high-grade pipes.

Jeff

Nick · Post by **Nick** » Wed Jan 12, 2005 9:05 am

Neat page Random. And yes to both you and Jeff, what I'm talking about is rounding out the edges of the draught hole as it enters the tobacco chamber. That's interesting that high graders do that. The reason I'm considering doing it is because the rounded edges create a much smoother, more laminar flow through the pipe, generating less turbulence. Mathematically, the results are pretty dramatic. I'm not sure how it effects things in the real world. But, as soon as I get my hands on a dremel, I intend to find out.

Nick · Post by **Nick** » Wed Jan 12, 2005 12:37 pm

I've atucally run a good few mathematical simulations and found that what you're saying is exactly right, with the exception of the draught hole diameter being some what irrelevant. The larget the draught hole, the lower the velocity, give a constant flow rate. At higher velocitis, turbulence is more likely to develop, thereby creating the eddies and vorticies that will cause the minute droplets of water to coalesce into larger, more problematic droplets.

Additionally, the spot where the passage actually begins is somthing I've been wrestling with. My initial thought was that the passage beagn at the bowl/draught passage junction. Then, after more research, I switched views to correspond to yours. Now after even more digging I'm back to my initial view. In my simulations, I presume the bowl itself is a sort of chamber containing the fluid to be carried through the pipe, and use formulae that accord this proposition. It is feasible to calculate flow from the opposite proposition as well. This issue seems like one where there's no real rigt or wrong answers, just differing approaches.

Thanks for the tip on the dremel handpiece too btw.