Actually wind blowing across the top of a chimney resulting in increased draft is an example of the Bernoulli Effect or Bernoulli Principle. Bernoulli preceded Venturi by about 40 years, and Venturi merely discovered that flow through a constriction causes an area of decreased pressure at the point of the constriction. What Venturi discovered was therefore merely a subset of the Bernoulli Principle, and is not applicable to chimneys unless they are at some point within their length constricted.Boots wrote:Not that I want in on the "argument" but I have not seen this posted yet,
the effect of wind blowing across the top of something (be it a straw with liquid, or a chimney with smoke we will call it a "tube" because I want to call it that.) and causing a draft is called the "venturi effect" by blowing across the top of the "tube" it creates an area of low pressure inside of the tube. And this low pressure area will be filled by whatever's on the other end of the tube. If you own any piece of equipment with a small engine, think lawn mower, the carburetor more than likely operates with the venturi effect. the more CFM of air that passes through the throat of the carb, the more fuel that gets pulled from the bowl and consumed by the engine. when you set the throttle on a small engine all you are controlling is a valve, just like a MPD. and depending on the positioning of this valve to allow more or less air flow, you get higher or lower RPM' s.
Now that being said, I did not post that in an effort to appose Stings science. I understand his point, I think. You cant get blood from a turnip. if there is not enough air in the boiler room having a second barro will do nothing but make a$50 bill disappear.
well, I stand corrected. I did not know that, I' ll have to do some research on that.lsayre wrote:
Actually wind blowing across the top of a chimney resulting in increased draft is an example of the Bernoulli Effect or Bernoulli Principle. Bernoulli preceded Venturi by about 40 years, and Venturi merely discovered that flow through a constriction causes an area of decreased pressure at the point of the constriction. What Venturi discovered was therefore merely a subset of the Bernoulli Principle, and is not applicable to chimneys unless they are at some point within their length constricted.
..... Any one else try a combo of the two to controll the wind gust spiking? 
Rob R. wrote:I just carried out a full tub of ashes and it was half empty by the time I got to the pile.
...... I hope you were up wind! Rob, the next time I see such wind I will try this and report what I discover.Rob R. wrote:Larry, try opening a window in the boiler area and see if you still get draft spikes.
I tried turning every which way, but I still ended up a hazy shade of grey.Lightning wrote:Rob R. wrote:I just carried out a full tub of ashes and it was half empty by the time I got to the pile.
Good reason to have that second ash pan or tub so you can wait for the wind to drop .Rob R. wrote:I just carried out a full tub of ashes and it was half empty by the time I got to the pile.
Can you believe that I have all of these tubs and I waited until a windy day to empty them?hcarlow wrote:Good reason to have that second ash pan or tub so you can wait for the wind to drop .Rob R. wrote:I just carried out a full tub of ashes and it was half empty by the time I got to the pile.
No time during the week to mess with it, and something came up on Saturday...so Sunday I was on my last tub and something had to done. (I only emptied two of them, the rest can wait until tonight)
Im with Ya Bro! Winds have been rippin' mad around here for 2 days now and snow is on the way... combo baro/mpd bearly handles the pull!Lightning wrote:Heavy winds here over the last 24 hours. My baro doin the best it can but its still hitting a .06 - .07" WC with the hard gales. I've been experimenting with using a combination of the MPD with the baro to keep it around a .03" WC.. Seems to work really good
