How Natural Draft Cooling Towers Work (Stack Effect)

[@savree-3d]

Want to continue learning about engineering with videos like this one? Then visit: courses.savree.com/ Want to teach/instruct with the 3D models shown in this video? Then visit: savree.com/en

[@Useratml]

can we say that natural draft= vacuum???

[@alwaysmabunda]

Best explanation, love this channel

[@kalebnotto1596]

I am going to have one of these build behind my house to cool my pc

[@tycoongamer2416]

😂i also want

[@Mega-P71]

INVEST INVEST INVEST

[@Jaguartmb]

You killed me

[@fokjohnpainkiller]

"Intel inside" huh?

[@ullianove151]

PC... powder by nuclear energy...🤣🤣🤣

[@jacquelinecammaerts6400]

For 50 years I have wondered how these work - now I know - fascinating and informative video - thank you

[@pvtaitchison]

Same here

[@ಶುಗರ್ಡ್ಯಾಡಿ]

50 years 😮😮

[@gwyn.]

Roshan NAIK Information was hard to come by People nowadays tend to neglect this fact.

[@stanly1543]

I cannot stress enough just how much John's videos have opened up my understanding of engineering principles and processes I once thought I was too... 'Dumb' to understand. His ability to convey how mechanisms work through both 3D animations and calm, un-hurried narration is second to none. Normally I dismiss KZbin creator's suggestions to subscribe to their paid content but, because HIS approach to teaching is so genuine and intuitive I subscribed for three months. Just for purely educational purposes.

[@stanly1543]

Sorry.... JON not John

[@jimanianortonified7015]

My friend’s young daughter thought those power plants were cloud factories and the finished product came out those towers.

[@MrChoklad]

well technically she's not completely wrong

[@Synthwave89]

@@MrChoklad She really is not wrong. Clouds are water condensation, exactly what comes out of those cooling towers.

[@maestrovso]

3-year-old child: look! Cloud making machines. QAnon adults: Look! Proof of deep state manufacturing fake climate change to curb our freedom.

[@homiespaghetti1522]

@@maestrovso perfectly logical

[@muizsp9525]

Just like what 6yo me think

[@cn9732]

Im 44 yrs old... And have litterally spent 30 yrs wondering about this. Thank you for scratching a 30 yr old itch!

[@rickyhermawan8979]

When I was a kid I thought radioactive smoke comes out of those cooling towers lol

[@ojkolsrud1]

Some adults still think that=P

[@paullangford8179]

Some places it does!

[@A.Martin]

@@paullangford8179 that water is not meant to have any contact with the potentially contaminated water of the reactor, It uses heat exchangers so the reactor water and the tower water are not mixing.

[@FlamingMonkey46]

@@A.Martin Unless your Britian circa 1950 and just decide to skip the research and build 2 open cycle air cooled reactors where air is just blown through the pile and staight out the chimney!

[@eamesaerospace2805]

Simpsons?

[@bgcgo5690]

My master's professor didn't even explain how a cooling tower works inside and expects us to know how to design an HVAC system for a building using both CWS and DX air conditioning. We were all lost! This has been extremely helpful!!! I'm preparing for final exams now and this has brought so much clarity into everything I was trying to memorize, which now I UNDERSTAND. THANK YOU.

[@k.chriscaldwell4141]

A natural draft cooling tower is essentially a huge vertical venturi tube. The added bonus is that as the hot humid air from the tower's base rises to pass thru the tower's constriction (throat), its velocity increases and its pressure drops (Bernoulli). This drop in pressure causes more water to condense out of the air mass (adiabatic cooling), creating a separate stream of hot air. This hot air stream accelerates the rising air mass and keeps it rising even after it clears the throat. Basically, a sort of ground level cumulusnimbus cloud maker. Cool!

[@captainotto]

I would expect the drift eliminator to be placed in the lowest pressure location in order to maximise the production of adiabatic condensate. But that's not the case in this schematic. Lowest pressure should be just atop of the narrowest section, same as you would have your atomiser in a carburettor. However, here it appears to be below the narrowest section, which is a region of high relative pressure. But then again, maybe there's other things going on or other considerations that aren't obvious to a casual observer like myself.

[@berkkaratoprak]

The most explanatory video I've ever seen.

[@PerfectInterview]

I'm a fast learner (I bore easily) but I really appreciate you taking the time to carefully explain everything. Most 10 minute KZbin explainer videos skip over important points (often because the creators themselves doesn't understand them) and you end up with more questions than answers.

[@savree-3d]

Good observation. Share your opinion concerning quick and easy videos that don't make much sense if you watch them a few times.

[@srisunkrish3513]

Thank you very much sir, now i clearly understood. I was amazed after hearing bacterial growth in cooling tower, thanks for the information.

[@PhilJonesIII]

Bacteria will grow almost anywhere and in the most unlikely places. It was the discovery of bacteria growing in Coke-plant effluent discharge (seriously toxic) that lead to the use of treating toxic industrial waste with bacteria. The result was the ability to treat chemical waste to the point where the discharge was drinkable.

[@HansLasser]

@@PhilJonesIII Right! They also use bacteria to treat arsenic loaded rain water coming from old mine tailings.

[@HansLasser]

Evaporative cooling is also used in many industrial refrigeration applications. Workers are made aware of the dangers presented by handling this water.

[@ramo1484]

This video is super helpful, I have no need to know this but it's really interesting

[@ParkerJonesmtb]

Great video! Will help for my 4th class power engineering exam :)

[@savree-3d]

Best of luck!

[@anoimo9013]

very good video. Id like to point out that the exit for the cooled water is wider and usually has grates to prevent plugging of the water circulation pumps

[@savree-3d]

Good point. We modelled a cooling water system (CWS) inlet with grates for a nuclear power station, and it was indeed much larger. The model did not exist when we made this video otherwise we would have most likely included it.

[@lukevvo5386]

Wow, that's an excellent, thorough and understandable explanation. THANK YOU!

[@charliepea]

Cooling towers fascinate me as a kid because of how oddly shaped they are. Now I finally understood how it works.

[@jujoya]

this is cool, you basically learn all those basic in high school, but the way they are used here in this big scale, its just amazing!

[@chrisreynolds3700]

I enjoy learning and your video is very educational. I get a clearer idea of what goes on in these towers now. They are so distinctive and intriguing looking structures, towers, and now I know more about them. So thankyou.

[@matthewgartell6380]

I remember Kearsley power station near Bolton getting demolished in mid 80s. We used to go down and get thousands of 20mm ceramic spheres and use them in our catapults. The glass industry around Bolton was booming

[@sumpyman]

I'm sure they'd mix a small amount of the incoming hot water with the cold water in the basin in winter. This will keep it around 5 degrees Celsius to stop it freezing and will cost them nothing.

[@A.Martin]

Thats what I figure would happen too.

[@jfleeman6776]

The cooling water never gets cold enough to freeze as long as the plant is running... The hotter water is continuously sent to the cooling tower.

[@CoolSs]

Cooling Towers are one of the most surreal designs

[@harshitanand3798]

Wow! So beautifully explained. Thank you so much.

[@fabioteixeira868]

For Winterization, why not just divert some of the hot intake water directly to the basin to keep it warm enough? Was kind of expecting that to be shown as the obvious solution...

[@captainotto]

It's a bit odd because another solution would be to simply install baffles to restrict airflow when freezing is a concern. You can compensate for lower temperature cooling air by reducing flow rate.

[@overunityinventor]

What's the temperature of hot water and cold water that this tower takes in and gives out?

[@dangidelta]

Why didn't I find you earlier. Just brilliant. The best explanation of cooling towers so far

[@maaliealhusseini5951]

The best video that I've ever seen in my life.. Thank you so much..

[@obaidahal-dannon3588]

Thank you so much, now i clearly understood.

[@ThomasSchick]

thank you for the free education...👍🏻

[@zdenko3228]

Thank you for your excellent video. Just a minor correction - the water molecules are not heavier than air, they are lighter. The reason water accumulates on the drift eliminator is that it mostly allows for deposition of already condensed water in the form of aerosol - tiny droplets. These droplets - not the individual molecules - are much heavier than the particles of gas. What happens is similar to sedimentation of a suspension in a centrifuge - in this case sedimentation of an aerosol.

[@suniltalks3577]

Please apload video on steam boiler like Cochran, locomotive, webcock and Wilcox boiler.

[@JonasSahlstrom1]

Thank you for bringing so much rain

[@Michal235]

You're a very competent teacher. Thank you for the video!

[@F34rwaffles]

just a thing; you went into calc III theories and i totally understood what you were saying. mad props; i owe my understanding of the difference of and the relationship between hyperboloids and hyperbolic paraboloids to you and this video. and i thought i was gonna learn about convection... mad thanks and props brother

[@F34rwaffles]

@@savree-3d gotchu

[@annaplojharova1400]

The draft has also another component forcing the air up than the heat alone: As the water have evaporated, there is way more water vapor in the "warm" air. And because water vapor is about half density than the air, the more humid air becomes less dense than the dryer air at the bottom. And the "drift eliminator" is not supposed to catch water molecules (these are actually lighter than air when in a vapor form), but to catch water droplets that have not evaporated, so those would present the real water loss.

[@theinko723]

Thanks for informative videos. It is good to have two more points. 1st, re-fill water pipes to replace that evaporated volume. 2nd, how air is passed through as cross flow, cases for low air flow versus high air flow due to windy day and why narrow bell shape body is needed.

[@drescherjm]

As a future electrical engineering student I got to tour a nuclear power pant in some time in the late 1980s that was going online. It was a very interesting tour. I did get to see the cooling towers up close.

[@rishabhasingh5155]

excellent ....love from INDIA🥰

[@chaos-ivy]

Absolutely saved me when writing a lab report

[@anandatk5377]

Technical know-how including Health and Safety knowledge! Thanks a lot.....

[@meaculpamishegas1121]

Why do they not have something like a turbo style generator to utilize the exhaust draft?

[@tonykarasek4816]

Outstanding presentation ! Thank you !

[@ailatejrithvik1564]

Great informative content and explained in great detail, I searched for so long, couldn't find anywhere.Thanks a lot.

[@SkumBanana]

Excellent explanation, thank you

[@HasiBuzzRaj]

Please upload "Air conditioning System" .... your explanation is great 👍 ....new subscriber 😋

[@rochahw]

Thank you so much for this video! I have just one doubt that doesn't got clear, I didn't understand the reasons of the shape of the tower (larger on top and thinner in the middle). Thank you!

[@rajivvyas9190]

loved the explanation thank you

[@AgravatVishal1997]

Boom, the best one

[@pyramidsciencefoundation]

I am writing a book on the specific geometric angle of 76.345 degrees. This is the angle of three dimensional Phi scaling. This angle shows up in pyramids, temples, cathedrals, DNA, etc., and per my online protractor app it appears to be the slant angle of the bottom portion of the cooling tower. Is there a way for me to verify the geometry of cooling towers? Is there a patent or blueprint drawings that would corroborate my protractor measurements?

[@abhishekdubey5326]

Very nice explanation. Thanks a lot!

[@savree-3d]

You're welcome

[@joaopaulodias1537]

Fantastic video, congratulations!

[@peckdec]

I think it should be mentioned that the drift eliminators only return the water in liquid form and not the evaporated gaseous water :) the evaporated water happily passes through as it is actually composed of smaller and lighter molecules than air.

[@PhilJonesIII]

Not quite. The change in direction results in what we call 'impingement'. The pressure at those points is higher and it does cause the water to condense. Not all of it, but certainly a good portion.

[@peckdec]

@@PhilJonesIII The dynamic pressure change is totally negligible in this case. The water would have to travel at much higher speeds. Drift eliminators are based on the fact that the more dense droplets tend to change their direction less than the steam, thus they gather and coalesce into the surfaces.

[@peckdec]

Also I want to add that steam does not necessarily condense when you increase the pressure. It can also superheat. This depends on the ratio of steam and liquid water in the container.

[@fahadqureshi9713]

Excellent video.

[@TheScreamingFrog916]

So It's a giant swamp cooler, like the one on my trailer. Go figure, LOL

[@alonzodesantis6989]

That's exactly what I thought swamp cooler

[@oa_math]

This is awesome, thank you!

[@ryandelong6504]

Excellent video, extremely informative and detailed. Thoroughly enjoyed the video. Just one tidbit bit of information jumped out at me.. "Forced draft cooling towers are rarely, if ever used" They're actually quite popular in the Oil and Gas refinery processing plants ! Albeit they are usually a different design, but they are out there ! :)

[@letstry7010]

Awesome vedio.... It clears my many concepts... Please keep on adding such 3D type vedioes... I am gonna to watch all 😍😍

[@letstry7010]

@@savree-3d already done

[@EatRawGarlic]

It's an interesting topic, but the same information could've easily been covered in half the time.

[@markproulx1472]

Good grief, no kidding!!!!!

[@akhirulfajar]

This video is part of a courses, that's why he's doing 7 minutes recap after 12:00

[@EatRawGarlic]

@@akhirulfajar The information density is low from the start.

[@DaveBeaven-tx2tp]

The plastic fill is similar to what was used in the cooling towers at Thorpe Marsh near Doncaster. The fill at the cooling Towers at Drakelow power Station was asbestos. I would love to get some technical information on the cooling system that was used at the cooling towers at Willington in Derbyshire. I think it could have been an old Marley Davenport cooling system at Willington given the age of the towers.

[@richardking6066]

Interesting! I'm curious to also know what the temperature gradient is across the system - ie by how many degrees is it cooled?

[@jasmynebrown1068]

40°C to 20°C

[@aaronmarkstaller]

Wait, why does the hyperboloid shape accelerate the air more than a cylinder if it expands at the top? And what makes the hyperboloid more cost effective than a cylinder or a frustrum? Also, why dos the concrete extend so far up past the drift eliminator? Thanks

[@aaronmarkstaller]

@@savree-3d Right, so would a frustrum have the same effect? And same strength?

[@ee4231]

Bernoulli's principle

[@THEL05]

Excellent !

[@ComputerWhiz_]

Excellent video! Very easy to understand.

[@MrChewmore]

Thank you for the video

[@amiraboodi2075]

thank you very very much. your videos are brilliant. please create more free videos for your youtube students.😊🌾

[@davidmizak4642]

You deliver excellent content to your audience. It's very interesting material. All of your effort put into creating this video is much appreciated. I'm truly grateful for your help!

[@savree-3d]

You are most welcome!

[@sarcasmo57]

We walked day and night by the big cooling tower, they have the plant but we have the power.

[@lingarajmishra8981]

Video was very informative,kindly make a video on the following points:- Range, Approach,cycle of concentration, NDCT heat load calculations and chemical dosing for tube scaling and biological fouling.

[@charlesdlamini8126]

Thank you very much

[@allezvenga7617]

Thanks for your sharing

[@maestrovso]

Thanks for making the video. Love the content. It is simple in principle but the complexities came towards the end - freezing, bacteria growth, and probably calcification. The pumps, and/or the infusion water of the entire system probably needs to be modulated to regulate the basin water temperature.

[@thijshuiberts2604]

why aren't the internals at the slim part of the tower? you would expect the velocity to be highest there right? so wouldn't that give a better cooling effect?

[@henryh.448]

@15:12 "The reason is, the water molecules are heavier than air." H2O molecule has a mass of 18u. O2 molecule has a mass of 32u. N2 molecule has a mass of 28u. Argon molecule has a mass of 40u. CO2 molecule has a mass of 44u. (u = mass of proton, which is also almost exactly the mass of a neutron.) So actually, the water molecule is lighter than all other common constituents of air. What is the real reason that water has a harder time ascending the u-bend in the drift-eliminator?

[@cs7160]

My guess is that the drift eliminator provides lots of contact area for the fine water mist to form droplets and for those droplets to agglomerate into bigger droplets. Once the droplets are a certain size, they cannot be carried by the air anymore and drip down. The shape of the drift eliminator is a trade off between offering lots of contact area for droplets to form, but not creating too much drag which will slow down the rising air.

[@matiasblanco2555]

Excellent video! Thank you.

[@savree-3d]

Glad it was helpful!

[@davidrenz5886]

Great stuff, thank you🙂...

[@jasmynebrown1068]

Very informative video

[@skunkjobb]

At 14:50 you describe the drift eliminator as if it catches water molecules due to their heavier weight compared to "air molecules". That is not the case. With a molecular mass (M) of 18, a water molecule is lighter than the dominant gases of air like N2 with M=28 and O2 with M=32. The drift eliminator does not catch water molecules in gas form (vapor), only droplets of liquid water. The water that has been evaporated in order to cool the larger portion of the water passes through the drift eliminator together with the air and condenses partially in contact with cooler surrounding air. Without the drift eliminator, there would be a greater loss of water that has not evaporated, a loss that does not contribute to the cooling capacity and is therefore not wanted. The vaporized water has to leave the tower, otherwise it would not work.

[@basavaraj]

Thanks

[@jianhuihong1]

I found a mistake in the video. You said water molecular is heavier than air. That is wrong. The reason water drips back down is because the water is in the form of small liquid droplets, not in the gas phase.

[@gamingnuur6092]

very informative

[@A.Martin]

You could just bypass some of the hot water straight to the basin to warm it if it is getting too cold in winter.

[@mikeall7012]

Our lage nuke plants, at my company, us a large gate for the pump suction basin, as opposed to a drain and pipe. That is because the suction demands for the pumps is quite large(~500kgpm). The pipes a several meters in size.

[@ArnoldsDesign]

Interesting

[@sharjeellaeeq4021]

Beautiful explanation!

[@omraikar8517]

Really helpful!!

[@savree-3d]

I'm so glad!

[@이성우-n5p]

Thank you for easy and precise information!

[@savree-3d]

You are welcome!

[@ashwynn4177]

Excellent video. Please make more

[@hakeemnaa]

12:00 the shape is to replicate venturi tube because the middle has smaller area,, the air will be faster and kinitic pressure will be lower ( kintic pressure from Barnoli equation ot static pressure p=f/a so, kinitic prressre does not depend on area. it is just opposit of velocity) which mean higher evaporation ( water can be boil by reduce the pressure) faster air and more evaporation by reduce pressue ( win win situation ) at top , the area is larger, which means lower speed and higher pressure and that leads to condensation ( water can condense by increase the pressure) the whole point is to cary the water molecules by the air at bottom before the middle and condence it before the going outside the tower they longer the tower, the more exchanging heat to the air without lossing much water

[@prasadpatel6508]

Extremely helpful 👍

[@amanbharti6054]

Which designing software are you using

[@JKTCGMV13]

Nice

[@savree-3d]

Thanks

[@tgozanski]

If very little water evaporates out of the tower, how come there's so much white "fog" coming out?

[@chazwalker7156]

@@savree-3d I think you've bamboozled him - he did ask tho, nice one 😆

[@oo0Spyder0oo]

For the same reason your kettle makes so much steam but very little evaporates from it.

[@MrThemold]

Expansion ratio is great.

[@suniltalks3577]

Thank you very much to understand for better way.

[@TheScreamingFrog916]

Wonder what it takes to filter out all the dust/pollen, that gets picked up by the water, as it go's through the cycle. The thing, is like a giant air filter, humidifier.

[@JunkBondTrader]

lol that's what I was thinking when I realized the clouds were water vapor. They should put a drop or two of Lemongrass essential oils in there and make the town smell good :P

[@DrFarazHarsini]

Awesome video!

[@back1114]

Really great explanation.. I am completely new to this and you explained it very well. Often it is super hard to explain something complex in a simple way. Thanks again! Well done! I will be looking for some more details about why the towers have the shape they have. I got from your video that it has to do with improving air circulation..??? But I would to understand better how the shape helps in this. I will try to check out some of your other videos. This was the first of your videos I watched. Again, well done and thanks a lot!!!

[@Captleemo]

By what percent does one of these cooling towers drop the water temperature?

[@DerekDavis213]

YES. That is the question.

[@Detailedstream]

Can they use natural draft cooling tower at (atmosphere Vortex engine) Tornado Generator that'll sucks all the waste heat and cooling water

[@marksinthehouse1968]

I’m amazed how the are built especially when you think when the first were built

[@zionpope9491]

Great !