Speed of bath draining

[Bod ...]

When I was working in QLD a freind asked me to plumb his surgery.
I wasn't up with the regs so washing facilities I oversized everything.

When inspected they failed it all as I was still undersized the grey and the foul water waste pipes.

Lesson taken on board. I always oversize wastes and condense pipes now.

They never block or freeze externally they look better.

 

[Mottie]

You must be an absolute hoot at parties

Sad fact here. Before I went to South Africa, I heard that water forms a whirlpool in the plug 'ole when draining in the southern hemisphere in the opposite direction to how it does in the northern hemisphere. I tried it and it did!

 

[fillyboy]

Sad fact here. Before I went to South Africa, I heard that water forms a whirlpool in the plug 'ole when draining in the southern hemisphere in the opposite direction to how it does in the northern hemisphere. I tried it and it did!

It may have been one of Michael Palins travel programmes where he demonstrated that, stood on the equator and poured water away 30 or so feet either side of the 'line'. Quite fascinating that it should be than precise.

 

[freddiemercurystwin]

Siphonic drainage has plenty of science behind it, that is the outlet and pipe sizes are all calculated, it works and is more common on huge industrial buildings, advantages are the pipes inside the building can be horizontal rather than needing a fall and reduced cost of installation, it's not something that would provide any benefit on anything smaller. But it does require attention to ensuring outlets are regularly checked.

 

[Brigadier]

Sad fact here. Before I went to South Africa, I heard that water forms a whirlpool in the plug 'ole when draining in the southern hemisphere in the opposite direction to how it does in the northern hemisphere. I tried it and it did!

It may have been one of Michael Palins travel programmes where he demonstrated that, stood on the equator and poured water away 30 or so feet either side of the 'line'. Quite fascinating that it should be than precise.

The shape of the outlet has far more bearing on the rotation, than whether it is north or south of the equator.

 

[Bod ...]

Sad fact here. Before I went to South Africa, I heard that water forms a whirlpool in the plug 'ole when draining in the southern hemisphere in the opposite direction to how it does in the northern hemisphere. I tried it and it did!

Have you seen what happens at the equator?

 

[Diver Fred]

It's the Coriolis Effect

Coriolis force - Wikipedia

en.m.wikipedia.org

 

[Harry Bloomfield]

You must be an absolute hoot at parties

I don't do parties, I find them extremely boring.

 

[JP_]

If you're in a hurry, get a walk-in-bath - they usually have 2 drains for faster emptying. And you can be lazy and open the door to leave!

 

[Harry Bloomfield]

If you're in a hurry, get a walk-in-bath - they usually have 2 drains for faster emptying. And you can be lazy and open the door to leave!

Who's in a hurry? Reach down, pull the plug/press the button, stand up, to towel off, step out and finish getting dry, and begin dressing.

 

[foxhole]

Mmm, an interesting theory and something I've wondered about for a while - the swirl or whirlpool effect slowing the drainage down. An idea I used to think might work, was baffles around the plug hole, to defeat the swirl effect. The way the pop-up seems to work, is by restricting the air being drawn in down the middle of the flow, increasing the vacuum effect, and the speed of the flow, despite restricting the overall cross-section.

I would be concerned about using siphonic drainage technics on gutters, because, the narrowed openings, increase the risks of blockages, from the likes of leaf debris.

On a different note - when washing and rinsing wine bottles, before I refill.... I find the washing and rinsing works much better with just a small amount of water in them, which is swirled round, than a larger fill of water. The final rinse, works best with an inch in the bottom, spun, then inverted to continue spinning as it drains.

The swirling allows more air to replace water thus aiding drainage .

 

[Harry Bloomfield]

The swirling allows more air to replace water thus aiding drainage .

Exactly! It's also a more efficient way to clean bottles and rinse them.

 

[Bod ...]

You must be an absolute hoot at parties

27 exchanges so far. Better than alot of other topic threads..

Starting a thread about Tottenham, would be interesting to see if it beats draining baths.

 

[Bod ...]

Interestingly, (same same but different) when in India the main topic of conversation was have you had a shịt today, and how was it.

Seriously (including Thailand) I could be having (Not just me) a conversation with the most beautiful Swedish girl and the conversation would be about having a shịt.

9 x out of 10 I would not wake up with her by my side but shịt was the top topic amongst back packers.

 

[Munroast]

Just something I've always possessed - an enquiring mind. I may get around to actually timing it, over the next two baths..

How would you quantify the volume of water. and if you use a bubble bath it could be difficult to time when it has drained!

A while back I was monitoring the kitchen sink, fully cleaned pipework it can drain a full sink in 18.6 seconds, when the wife starts to inform me "That Sinks Not Draining Properly" it will be around 70 seconds

What I found was it is the very last bend that congeals with fatty stuff, and if I heat that bend with a hot air gun I burn the house down - no seriously, heat it with a hot air gun and run some very hot water through and that improves drainage speeds, so for instance if it is running at 50 seconds, the hot air gun trick an improve it to may be 35 or 40 seconds

just done a test drain now (first one since last july when it was 38 seconds) and tonight it was 29. So a little clearer than 7 months ago without doing anything between those dates