The Fluid Effects That Kill Pumps
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- Опубликовано: 2 июн 2024
- Three hydraulic effects that ruin a pump.
We collectively move incredible volumes of fresh water, drainage, and wastewater into, out of, and around our cities every day. And, we mostly do it using pumps. I love pumps. But, even though they are critical for the safety, health, and well-being of huge populations of people, there are a lot of things that can go wrong if not properly designed and operated.
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This is not engineering advice. Everything here is for informational and entertainment purposes only. Contact an engineer licensed to practice in your area if you need professional advice or services. All non-licensed clips used for fair use commentary, criticism, and educational purposes.
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Assistant Producer: Wesley Crump
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@@tafdiz He already told us about her 3:47
Just so so cute everything and best the hungry kid and the i love pumps ❤️
Grady, There is a video on the YT channel 74Gear, where the channel owner, Kelsey, was reviewing and debunking the fearmongering video "World's Most Dangerous Airports." While talking about Madeira Airport in Portugal, he missed the comment that the airport "was one of the only airports built by engineers". Also due to the nature of the geography of where the airport was built, civil engineers had to design the runway to be supported by 180 concrete pillars. The narrator stated that the runway would collapse, "if an airplane would land too hard on the runway". (Kelsey did correctly point out that should such a landing were to happen, the forces involved would destroy the airplane long before the runway would collapse.)
I would love to hear your comments about the airport (and the misinformation being spread). Here's Kelsey's video at the spot where he starts talking about Madeira Airport: ruclips.net/video/igDPP7ZwVhs/видео.html
@@obsculor Oh, and Grady didn't state if this was a 747 in the passenger or cargo configurations, either, as there are difference between the two. And, having worked in the air cargo industry a few decades ago, we also need to find out if this is "fully loaded" by weight or volume.
I think we need to bring in Kelsey from the RUclips channel 74Gear, as he's a 747 pilot who's flown both cargo and passengers.
@@jackielinde7568 I often fly to Madeira and have an house and family there. some even worked in the construction. it wasn't built by engineers. it was build by construction workers. engineers don't build anything. they just plan it alongside architects. airport is nothing special. the biggest dangers are the weather and strong wind. it's not rare that airplanes have to divert. airport is much safer now with a longer runway. it was more dangerous in the past. it's certainly a lot safer than going by ship. no one ever thinks about the pillars.
The “I love pumps” has “I love refrigerators” energy.
I love that clip! Hope someone clips it and insert it into their video every time they talk about pumps!
He needs to talk about the engineering of refrigerators now to complete the cycle.
@@okj890 Grady Connections
I love lamp.
tecnology conections wants to know where your heatpump sits
I had a desk fan at a miserable job which I labeled plainly "THIS SUCKS" on one side and "THIS BLOWS" on the other.
Net sum is zero
Actually a fan slices the air into smaller amounts and slings and pushes it away.
The mom & pop store I worked at preordered seasonal fans and heaters from a bulk shipper who got all his stuff from China. One year we got 200 box fans that had something weird with their blades. They made a ton of noise but blew very little air compared to previous models.
@@michaelrief4424 That very much depends on the type of fan. See @obsolete professor.
@@mattmurphy7030 😂😂😂
5:52 - "But it does make a bad sound when there isn't enough positive suction head at the inlet."
Pump: **UNHAPPY PUMP GARGLING**
Sound of a cavitating pump is even a lot worse.
SUCCTIONTIME SADNESS
It sounds like it's drowning
Poor Pump😔
It's amazing to me how you regularly manage to extract the gist from complex engineering fields and then present it in such a laid back and presentable fashion, disguising how much effort and research goes into each video. I salute you.
Nilex: He makes this look easy, a phenomenon of elite performance. Did you ever see Carl Lewis run? This is the Carl Lewis of RUclips engineering videos.
Me: * google carl Lewis running
I like big pumps, and I cannot lie!
No infrastructure can deny…
When a pump walks in with an impeller and a shroud, you get spun.
Baby got flow!
Nice work fellas!
@@danacoleman4007 Indeed!
Two guys with better rhymes than the whole mainstream industry^^
Which is easy but... Still great :D
This T-shirt idea is one Grady can't pass.
Can you cover sewage treatment pants? I'm curious how they deal with solids in the pump paths.
I need to get me some of those "sewage treatment pants".
@@petehiggins33 Sci-fi high tech diapers!
@@petehiggins33 Hahaha! Your comment is too funny. I'm gonna leave the typo
Can you discuss sludge pumps? Why they can pump tons of sand. Even rock, what kind of impeller is used and what are the parameters needed to make them function. Thanks
@@randomshitbekker yep diaphragm pumps are pretty intense. Can literally pump steel ball bearings lol
Wildland firefighter trick. You’ll often see an empty water or Gatorade bottle floating on the top of the portable tanks when we’re drafting water from them. It disrupts any vortex that starts to form, thus preventing loss of prime.
If we have a booster line available, we remove the nozzle from it and use that as a return line when we use a drop tank in rural structural firefighting.
That does double duty in preventing a vortex and loss of prime plus increasing the cooling capacity for the pump when the attack crew isn't actively flowing water.
However, it's rare our department uses drop tanks. We usually prefer to nurse feed the engine, giving us more water available faster than setting up a drop tank with our limited manpower, then letting the next arriving tankers keep ours full.
@@leehuff2330 How does the return line prevent a vortex from forming? If anything I would think it would cause a circular flow which could help produce a vortex.
Agreed, when we draft from drop tanks we will throw a water bottle in to stop this vortex
...What if you used an empty Prime bottle? The lack of Prime prevents it from losing prime!
@@alexandermcclure6185 i knew this pun was coming
"Honey! The neighbors are pumping water up a ladder again!"
The twinkle in his eye when he said "I love pumps" made me smile and laugh.
he gets pumped about pumps lol
You can absolutely see his excitement for this topic
I live in The Netherlands and this subject really gets me pumped
Ikr. The build up in the video is strong.
A nation where the pump engineers are gods.
As a citizen of Flevoland, i'll happily sing "pump up the volume .. of water"
Reminds me of what my grandad used to tell me: “Oklahoma is so windy because Texas sucks and Kansas blows.” Lol!
LMAO
Yup....living in KS and it does blow....also lived in TX before moving here and it does suck.
Similarly, for why the prevailing winds blow west to wast in Pennsylvania... Philadelphia ducks and Pittsburgh blows.
Thats funny
1 guy sucks and 1 girl blows. Okay.
Rockets often have vortexing problems in their propellent tanks particularly as the tanks empty. They often solve it with special vanes with carefully arranged patterns of holes in them that slow and break up the vortices and prevent gas ingress.
They need some people in there with giant scissors, cutting off the tails of the vortices, easy fix!
@sehhi vooty why do you have such a fake account when you're typing an actual real comment? (unless it was copied from someone else)
Is this the nerd behind the scam account talking?
EDIT: nvm, i just found the real comment you copied..
FrankH 4 months ago
On scale models: There's a model of the entire Mississippi river system somewhere (now abandoned), and also one of the SF Bay / Sacramento Delta.
Even that comment has one of you fake bots copying another person's joke underneath it.
Gah.... this is so sad.
@@Games_and_Music There's a tool made by a RUclipsr called ThioJoe that can automatically scan for and report spam comments. It's a little complex to setup but not too bad. ThioJoe used to make fake/scammy 'help' videos but turned himself around and started making really helpful and informative videos. Been trying to spread the word around as the more people that report these spammers the faster their spam can get deleted. Channel owners/moderators can also use the tool to directly delete spam comments.
Chao mang dao fin lai, suk chom lai fao dong. Laer bo bai mou himsongfaibo. Chom sing duk dao!
I wonder if collapsible type containers can be used to avoid the creation of empty space while sucking the gases or fluids out, like a syringe type mechanism that never allows the formation of space by constantly matching/adjusting to the level of the fluid.
I clicked on the video so quickly it made a water hammer.
I cavitated that like button
I was primed to the subscribe button.
The quality of word play here has slowed to a trickle.....
¯\_(ツ)_/¯
Vortice all ziz?
@@gus473 All the humour got drained away.
Aquariums:-
What I see: flora & fauna
What Grady sees: pumps, vortices & NPSH
I love pumps lol
On scale models: There's a model of the entire Mississippi river system somewhere (now abandoned), and also one of the SF Bay / Sacramento Delta.
I visited the scale model, it was awesome!
It was in the U.S. Army Corps of Engineers building right across the bridge.
@@nater308 The model of the complete Mississippi R basin was in a field east of Vicksburg, MS. It included all of the rivers emptying into the Mississippi from the Rocky Mountains on the west to the Appalachians on the east. The model at Vicksburg was of the lower Mississippi basin from around Arkansas to the Gulf of Mexico and included the Atchafalaya R and floodway to Morgan City, LA. This one is not exactly small by itself.
I've been inside the West Closure complex. I was a reporter at the time and I was sent to the first test of the pump. It was an incredible experience.
If anyone hasn't looked into it, check out the history of London's sewer pumping stations and the story behind the construction of that tunnel network. It's pretty incredible.
There's a great documentary about it:
en.wikipedia.org/wiki/Seven_Wonders_of_the_Industrial_World#The_Sewer_King
The entire series is worth watching. So is this one:
en.wikipedia.org/wiki/What_the_Industrial_Revolution_Did_for_Us
True. And boy was it necessary ^^
@@peterfireflylund I remember that show!
I wouldn't mind seeing a Jay Foreman video on the topic.
That is a unique way to water your lawn; pump on a ladder!
As always, thanks for sharing such great information and demonstrations!
I ran into one of these videos by accident like a year ago, and now here I am, a fully fledged infrastructure nerd. I don't even know when the transition happened.
These vortexes have interesting positive implementations too. Vortex Flow Control systems are used to have a fixed outflow of a storm water system regardless of the water pressure at the inflow. The higer the water rises, the bigger the vortex gets and the more air gets 'pumped' through the opening. Thus hindering the water and capping the outflow.
In Belgium we use these since we want to create buffers for storm water and waterway managers don't want to big of an inflow in their streams.
Another great video! I like how you mentioned the depth of the pump suction piping, then almost immediately mentioned raw water intakes. As a water treatment plant operator, this is something we deal with first hand. Our source (raw) water intake pumps are set in a wet well that collects river sludge rather quickly. We do have this wet well cleaned annually, so we never have issues with the sludge reaching the pumps. But, if the pumps were mounted too low, it would easily start sucking in foreign objects until inevitable pump failure. We are able to get about 25,000 hours out of these pumps with river conditions of 0-300 NTU, then they must be replaced. This typically costs around $50k to replace a pump, balance the shafts, and go through the motor. Anyway, I’ll stop rambling. Thank you for posting these great videos!
That's decent hours. I look after dewatering on a large gold mine with multiple surface and underground operations within the one mine on a salt lake with hyper saline water. The water is so salty we have to flush the pumps and lines with fresh water twice a day for half an hour each just to maintain flow. All of the surface pumps are diesel driven with the wet ends getting at best 5000 hours before needing rebuilt or replaced.
"Capable of lifting the equivalent of fully loaded Boeing 747 every second" - Ah yes, freedom units!
What's the equivalent of that in airbus🤔
America, the only country so uncomfortable with metric, we'll literally measure with anything.
Be grateful he converted pizza baking time into seconds so we SI users can understand
@@taktuscat4250 what do you mean? African or European passengers?
@@OrionMelodyMusic Random sample of both
I remember when I started my current job in the boiler room at a local small-town plant (no engineering background - only basic college physics and some calculus). I noticed that the feedwater pumps regularly had issues, and I eventually figured out that air kept getting trapped in multiple locations in and around the pumps, causing poor flow, hammering, and cavitation. Once I became the lead boiler operator a few years later, I made some modifications. Since the deaerator tank sat about 10 feet above the pump platform, it provided decent enough head pressure that I was able to add 1/4" diameter vent pipes at each high point that allowed anyone to open up the valves and let the water push the trapped air out. It's been _years_ since we've had to replace an impeller that was turned into swiss cheese by cavitation.
One of my favorite vortex solutions was a tennis ball. The floating ball would be drawn toward the low pressure (where the vortex is beginning) and would then prevent air being drawn down into the pump inlet. The buoyancy of the ball was enough to overcome the low pressure.
Very interesting! In one of my dialysis clinics we have a 200gal. storage tank for RO water, and when I run that tank down to about the 40 gal level to add disinfectant, I begin to worry about pump cavitation at that lower water level. I wonder if an appropriate-sized hollow plastic ball (polypro or teflon) left in the storage tank would offer that same protection. I had been thinking of adding some vertical vanes in a starburst pattern in the bottom of the tank to do the same thing, but a single hollow plastic ball is a much simpler solution!
Now this is a RUclips video that doesn't create a pressure differential between its intake and output side (it neither sucks nor blows)!
Tom Scott did an interesting short on the Ruhr Valley pump system. Because of underground mining, land in parts of the valley have dropped. They have to pump water from the Boye River up into another river otherwise a huge chunk of the valley will flood.
Same in loads of the Netherlands really. Even Amsterdam. That's what you get when you drain areas and then extract the peat to burn for warmth.
@@woutervanr what does peat do?
@@joeyknight8272 It holds water really well. It was more about first draining a bit and then digging up even more and then building there that is the issue. Be it peat that is dug up or anything else.
@@woutervanr can we grow back peat?
@@joeyknight8272 Well yes in the same way that we can grow back coal. Peat is an earlier "life stage" of coal. I'm not an expert but coal takes millions of year I think, peat maybe "only" some 10000. Google a bit around if you want to know more.
3:45 Grady's commitment to "one side sucks and one side blows" has earned him even greater respect and honor 😆
As a young civil engineer, I'd love someone like you as a mentor. The way you explain things, making them easy to understand is a skill! Another great video 👌🏼
So pumped up for this video!
"One side sucks and one side blows"
I usually do own thing while listening, and this caught me off guard. I had to stop and think for a sec here.
As someone who manages water and Wastewater infrastructure construction projects I love videos like this!
10:14 Oh wow I didn't know they came with edible recipe cards. Truly efficient packaging.
0:15
translation for non americans:
fully loaded beoing 747 can be 333 t to 397 t, depending on the model. I assumed that fully loaded meant the maximum take-off weight
Outside the US there aren't any airplanes nor airports.
So we all wild canibals living off civilisation thank you so much for your worthy explanation.
@@pleindespoir even in America there are no planes. It's just cgi to fool you into thinking we are superior.
Seriously though, "as much as a 747" is just a roughly understandable scale that's just a little more accurate than "more than a car, less than a mountain"
@@pleindespoir or you could just say thank you (because you didn't know how much a fully loaded Boeing 747 weighed and someone did the math for you).
@@glasstuna "more than a car, less than a mountain"
I'm so sorry, but due to my life in wilderness on another continent than America, I don't even know the meaning of "a car".
Hello from a non yankey, thanks for the numbers😂
This also applies to oil pumps. When I dropped my motorcycle, air from the sump got into the oil pump, and the 'low oil pressure' light came on. The solution was to 'burp' the filter by temporarily loosening it so that the trapped air could escape.
I'm doing an internship at an HVAC equipment supply company selecting hydronic equipment. I've definitely learned to love pumps 👍
I have noticed at work that when vortices form in the coffee urns when we clean them, they drain much more slowly.
"She's gone from SUCK, to BLOW!"
-Spaceballs: the comment.
Spaceball One transforms to Mega Maid.
1-2-3-4-5 That's the combination on my luggage!
At least I'm not surrounded by A holes in this thread.
;-)
We've lost the bleeps, the sweeps, and the creeps!
When building small scale models, is everything is just scaled down in size, or things like density of water, surface tension etc are taken into account?
You need a degree to answer all of the scale factors: density, viscosity, etc.
We use the Buckingham π theorem to scale models in fluid dynamics
As Vlododymr says, Buckingham Pi theory allows for the use of non dimensionalised parameters to map the characteristics of the model system to the real world system. These non dimensional parameters depend on what parameters (and their dimensions) are relevant to the real world system. I think a video on it would be nice, but I don't think it would suit Grady's style.
@@terminus.est. what
When my Dad was doing the design studies for a beach foreshore storm defence he was searching for a suitable scale media to represent the sands and gravels in the bay. In the end the best substitute turned out to be windblown sand, so a truckload was ordered for the 100’ x 100’ outdoor wave tank. It worked, the beach has survived since the early ‘60’s.
3:46
A new legend is born
For the vortex problem:
My friend is a fireman in a rural area where there is no water distribution or hydrants, but lots of lakes and streams. A common way they get water is to to get a portable gas powered pump to the lake or stream. They send water into a portable pool like reservoir that the pumper truck pulls from. The pool acts like an accumulator as they'll often run several pumps. However, vortices often form in the pool. Their solution: they have a compartment in the firetruck full of volleyballs. Toss a volleyball into the pool and it "plugs" the vortex preventing it from reaching the inlet hose!
Grady: "You can't just indiscriminately oversize expensive infrastructure."
AASHTO: "Hold my beer."
If it's worth building, it's worth overbuilding.
I had the chance while studying to visit one of those scale hydraulic model facility. My favorite part was the fact that they use very, very fine sand (in fact, it's calibrated to respect the scale order) in order to replicate the behaviour the sand would have in real life
Excellent video! I'm a civil engineer and have designed pumping stations for raw water, potable water (including municipal well pumps), sanitary sewage, and storm drainage. I have also debugged more than a half dozen pumping stations that didn't work correctly due to poor design.
The worst I dealt with was six grit removal pumps at a brand new wastewater treatment plant where a design error (the engineer had assumed much too low a suction head, so the pump moved right on its performance curve), two construction errors (the contractor free-lanced a change in the discharge piping that reduced head losses, causing the pump to move even further to the right, plus setting too low a pressure on the flush water for the mechanical seal, which allowed grit to enter the seals and damage them), and a programming error (the grit chambers had a pressurized air feed to keep the grit fluidized when the pumps were off, but the programmer flipped it so air was pumped in only when the pumps were on, which meant air entered the pump suction). Unfortunately, the pump engineer and the programmer were from the company I was with at the time and the pump engineer had left the company and the country and taken his design files with him. However, I figured out his error and we worked through the others. The plant lost five of the six pumps before I could even get to the site to investigate. The remaining pump sounded like a popcorn popper and the volute was probably 20 degrees above ambient. Fun times.
As a pool guy you dont know how often I have to tell my clients if the pump runs dry... the seal overheats and fails.... and the watery bits gets to mix with the electrical bits... THIS IS BAD!
Love your videos ... keep up the good work!
This was pretty cool. I would have liked more detail on the geometric elements used to suppress vortex formation, but otherwise incredibly interesting.
The moment you realize the comment section is filled with a bunch of 14 year olds giggling at the specific words Grady used.
Hey, at least they're here because they're interested in engineering topics!
He takes Engineering and Science SERIOUSLY. Just another reason the USA is falling behind in these areas when those watching this video think it’s amusing and find it funny. Maybe those folks would be better off watching Crank Yankers.
@@michaelrief4424 Oof. No fun allowed in the USA. Glad I don't live there. ;)
I'm 28 :< And come on, it's just fun ;) And the important thing is that we all watched the whole video to learn something about pumps. Our youth should be more interested in science and engineering.
@@michaelrief4424 You know that people can combine fun with science and engineering ;)
I work at a large wastewater plant and use pumps of all kinds. The last interesting thing I’ve pumped was crystalline struvite in a slurry with a positive displacement pump. The pump is 100hp, the 10” pipe is five and a half miles long and the discharge is 14 feet below the pump.
Struvite is the bane of anaerobic digestion!
I'm a Power Engineer, your video is thorough and concise enough to explain weeks of schooling. I'm surprised you didn't mention the implication of a foot valve, a check valve to hold prime. Otherwise amazing video!
Definition of pump:
"ONE SIDE SUCKS AND ONE SIDE BLOWS."
.... Grady 2021
He deserves a place in meme history for this and the memes who will follow
"I love pumps."
I dunno, Grady--You look like more of a sneakers guy to me, but you do you.
buahahaha. Bet he did not expect that to be perceived from this.
I can’t even begin to tell you how useful your videos are to understanding engineering concepts which aren’t usually very clear in written descriptions found elsewhere. Thank you very much for making them.
Im so happy you're talking about pumps! so many people have no idea what goes on behind the scenes and how complex they can be. Thank you for all of this.
"It's hard to predict when and where a vortex will form, even with advanced computer modeling"
Reason #162 why I became an electrical engineer.
Electricity and electronics I understand. Mechanics and mechanical devices I understand. Hydraulics and fluid dynamics are voodoo.
Tell me about eddy currents? :)
@@AlexanderBurgers Give me a thumbs-up with your right hand and call your thumb "Eddy".
@@AlexanderBurgers lookup non-destructive inspection and you'll find your answer.
Has to do with magnets....however the heck those work....
ammirite fellas?
Electrical currents and wave theory; why I became a Mechanical Engineer.
Happy 2 million (almost) subs to Grady and his blue water.
I love them too, at large water parks seeing the massive vertical mounted giant VFD vector driven motors PWM humming away draws my eyes to them, as their shafts go down into a pump cavity with a good 10 inches of pipes coming out both sides, just imagining how many GPM is flowing through them to keep one of our largest waterparks going... good stuff, thank you.
i was playing subnautica and had no clue what the cyclops meant when i entered flank speed, "warning, vessel caveating, excessive noise" and i recalled "oh yea, thats what kills pumps. it's when air comes out of the fluid and gos back in, creating a shockwave damaging the prop and telling the reaper right where i am"
and honestly i love watching your videos while i eat my food, its nice to learn and nourish at the same time
I love watching nominative determinism engineering with Gradient Hill House
Cities Skylines has taught me the importance of pumps, yes.
Especially sewage pumps.
@Is me ? Country roads~
Love your channel. The calm and controlled way you explain things is very effective, and easy to listen to.
One device that I see problems with when not installed properly is expansion tanks on closed loop chilled/hot water systems where there can be large fluctuations in water temperatures. Even if the system is filled/purged properly; as temps shift, pressure drops across the pumps and their pipes can vary greatly causing damage though (and you mentioned these) dead head, cavitation, seizing and/or blown seals, etc.
"How geometrically pleasing to the eye!" Sounds like you've found a kindred spirit there, Grady! Great video as always, I love how the vortex twists up and around into the pipe--so cool!
Pumping liquid propane has its own unique problems because it can change from liquid to gas with just a change in pressure.
Still better than that bastard gas butane i tell you hwat
Hahahahahahahahahahaha
So can water!
heeeeyyy i brought the pumps there, and alotta other parts as well. it has Cat C280’s V12’s that burn 250 gallons of fuel per hour and they have 11 ✌🏻also the WCC uses propeller pumps that are submerged all the time
So part of my family's vacation there next year is dependent of the parts you delivered. It's a small world.
The thing that is outstanding about this channel is that you're freely giving very, very VERY valuable information to absolutely every one. Thus giving us some understanding about the day-to-day uses of every thing that surrounds us. Information that becomes very useful in the case of an emergency. With shared knowledge, and better understanding of the things that surround us, we're able to work out solutions, and make more sensible choices.
Thank you so much, I'm learning a lot with your videos and it's incredible how clear and easy to understand your videos are. Despite the complicated topics that you go over sometimes !
Just what I needed. A fresh batch of knowledge on mechanisms that suck, blow and need a good head to work.
Everyone else here is snickering at the “one side sucks, one side blows” comment, meanwhile I’m here spitting my tea over the term “suction head”.
5:58 that there is the sound of bad head
Suction Head? Yeah, I went out with her a few times. Unfortunate nickname.
@@tncorgi92 Cheap date. All she need was a few bottles of water and some napkins.
"I love pumps" I'm sure you do Grady. I'm sure you do.
Point of clarification around the 5-minute mark. When pump manufacturers are telling you the NSPHR (Net Positive Suction Head Required), what they are really telling you is the "NPSH3", which is the NPSH at which the pump is cavitating enough to reduce the discharge head by 3%. For example, if you have a pump that is supposed to be producing 100 feet of head at a given flow rate (per its performance curve) and the NPSHR curve indicates that the pump requires 10 feet of head at said flow rate, then if you only give it 10 feet of suction head, then the pump WILL be cavitating, and you can only expect the pump to produce 97 feet of head. Typically users are required to provide the pumps with additional NPSH above the published NPSHR (NPSH3), known as NPSH margin. The margin can be measured as a fixed amount or as a percentage. To actually fully suppress ALL cavitation, the actual amount of NPSH needed could be many times higher than the published NPSH, sometimes as much as 20x higher. This is obviously impractical. Let's say that the example pump is supplied with 13 feet of NPSH, meaning it has a 3-foot NPSH margin. The pump would likely still be cavitating a small amount, but at a tolerable level where the reduction in discharge head is negligible and the life of the pump is not severely reduced.
At 5:36 - where the pump is moved to the top of ladder - it is stated "the suction pressure just about doubles". No, it doesn't. The suction pressure is actually reduced, partly because of the increased static lift (vertical distance from the water surface to the pump) and partly because of the additional friction due to the longer suction pipe the fluid has to travel through. I believe you meant to say "the suction pressure REDUCTION just about doubles."
Other than these nit-picky details, your video is very well done and I think does a good job to illustrate complex concepts.
Regards, an engineer who works for a major pump company
Thank you so much for clarifying "The suction pressure just about doubles" because this was bugging me out and I went to the comments to look for someone to catch this.
Huzzah, a new video! Thank you for your time and effort in creating these videos. Even if I already understand the concepts I just enjoy your explanations. Great work, can't wait to see the next video.
3:47 “One side sucks, and one side blows.”
For a second there, I thought it meant the same thing… in different context.
You're a man of culture i see.
How about a floating object on top of the water stream to stop a vortex from forming? it will always be pulled into the center of a vortex immediately extinguishing it.
I've seen this used a lot with smaller pumps or inlets, for example in videos about homemade hydroelectric systems.
Open the pumps, HAL.
@@Misack8 I'm sorry Misac. I'm afraid i can't do that.
At my old job we had a sump pump burn out as well as three replacements before we discovered that a change in the sump pit that was made by construction workers that had done a bunch of stuff on the building made a perfect environment for a whirlpool to happen feeding air into the pump. Just taking an inch of stone from the bottom fixed the problem and the latest pump was still working when I left the company. I thought it was just a freak occurrence but turns out that it is a thing lol. Love these vids. Keep up the awesome work.
Very interesting topic indeed! Worked for over 30 years on all kinds of pumps in the nuclear waste industry.
Okay the "I love pumps" T-Shirt just has to happen.
I am so close to my Practical Engineering degree I can taste it.
The sheer excitement you get cracks me up every time man. Thanks for the awesome and informative vids!!
I really enjoy watching your Practical Engineering videos! Thank you for keeping a large group of people informed about the things we don't get to see on the daily!
"One side sucks and one side blows" my maaaan
"I've got some colored water and clear pipe in my garage..."
Aw, c'mon; now you're just readin the comments.
I always enjoy your videos! I live on the Mississippi in the same city as Carver pump company. We were fortunate to get classroom visits from engineers in science classes. They would bring cut away pumps & damaged ones. Thanks for all that you share!
Wooo. Just about 2 mil subs! Congrats!
Hope you and the family are well!
Grady: "I love pumps!"
Grady's fans: "You don't say!"
"One side sucks, one side blows", this is an Old Tony level joke!
Thank you for the amazing content Grady!
Fascinating, as always. Love your channel.
3:47 - "One side sucks, and one side blows"
-Grady Hillhouse, 2021
"Don't mash it"
My wife says the same thing to me, slightly different situation though.
Grady, I’m so incredibly happy with the more frequent uploads. Keep up the amazing work!
I sincerely thank you for the great demonstrations and explanations, as usual.
"In very simple terms, one side sucks and one side blows."
I like how you snuck a political statement into there. :)
EXCELLENT video once again. Thank you!
Great video as usual mate, Anti-vortex plate or fitting a bellmouth at the end of the suction pipe are great ways to limit the chance of surface vortices forming. In waste water (sewerage) pump stations operating the pump down to a low level once or twice a day allowing a vortex to form is actually a good way to remove surface build up which is a common issue. Very short periods say just under 10sec has limited negative affect.
3:45 "In very simple terms, one side sucks and one side blows."
So basically any 2 party political system?
Like every political system. Humans apparently can't remember more than two arguments, so even countries with multiple parties are a 2 sided system... Germany is the perfect example. Here in Switzerland it's exactly the same too.
In the east it's also a 2 party system, just with another execution (pun intended...)
"One side sucks and one side blows."
Well sometimes its the same side doing both.
really enjoying your vids!!! you bring a gentle presentation to complex physics!
Great video! Thank you guys!
“One side sucks and one side blows”? He should have said, “no pun intended” afterwards.
Please don't use 747s as a unit of mass.
He cant use football fields since they are 2d, theres nothing else he can use
I can remember when African elephants used to be the universal unit of mass or was it London double decker buses?
@@zeroskill. Olympic swimming pools would make more sense, though I'm opposed to that too.
Sounds like those freedom units
Why
These are crucial design considerations that are too often overlooked. Great content! Thank You!
nicely explained , well done