Engineering estimate: Let's assume the wire is coiled in such a way as
to represent a cross-sectional area (when looking through the tube like
a telescope) of 1 square inch. That seems hign but let's go with it.
Now a 4 inch diameter tube has a cross sectional area of 12.5 square
inches. Thus, I claim approximately 8% of the are is lost so there's an
8% loss of vacuum every foot.
My 1 inch is probably high, it's probably closed to one tenth of an
inch so the result is closer to 0.8 percent.
I know nothing about fluid mechanics except that my roommate used to
spend entire nights doing the homework (I was in electrical
engineering, he in mechanical). However, I'll bet that my super simple
minded approach here is not that far off.
Dave, sorry for taking your humorous answer so seriously.
Dave Hinz wrote:
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.