Thanks for this. I only heard of water hammer a fortnight to 1 month ago when it happened at our house. It just happened again today. I looked into it a bit 1 month ago and understood it a bit but I know understand a lot more about it since watching your video. You are really good at explaining it so people can understand exactly what is going on when water hammer happens.
what I can say is I'm so pleased to watch your video Eng. Mike because it made easier the introduction to water hammer. thanks for your time helping me and others
Thank you very much I have a research problem in a refinery where a sudden closure of a valve caused damage to an expansion joint I need help to calculate the pressure rise that caused the failure
A question Mr. Crowley, what about if we have a centrifugal pump working and suddenly somebody shut-off the valve very fast, this shockwave is going to act on the spiral volute of the pump or just inside the pipe.
In my industry we have been facing an unique water hammer problem which has been developed to deliver max 6bar pressure via pump automation. The logic was to turn off the pump by pressure switch when the pipe pressure reaches 6+ bar. And when the pipe end valve will open and pipe pressure drops below 3bar then the pump will start. Logically its working but we are facing water hammer problem when the pipe end valve shuts. During that phase the pressure wave oscillates violently 0 to 10 bar. It causes to turn on and off the pump via pressure switch. Point to be noted, there is a non-return valve after pump delivery point and before pressure switches. It happens for few minutes. I am thinking to place a non-return valve at pressure switch outlet point to control the reverse pressure wave, will it work?
i want to solve a transient problem in pipelines which is connected in series. three pipes r connected with each other with reducing diameter. this problem is give in the book titled hydraulic transients by streeter and wiley. but i cant able to solve this problem. please help me in this matter. thanks
before i am very thank full to professor (mike crowley) has posted about water hammer video which very help me cause i am student of mechanical engineering having thesis to analysis of fluid dynamic phenomena concerning on water hammer (creating hydraulic ram pump with harnessing water hammer as main power). But i still confusing about effect of water hammer after it is rising up the pressure causes water having supersonic velocity after the valve closed, my question actually very simple but i still cannot get the answer. "after water hammer happened, the water's behave always makes reflection cause the valve closed...and how long the reflection of water inside the pipe ?" Hopefully you can reply my question, that is big favorable to me...
Every cycle the amplitude gets a little bit less due to friction and the inelastic behavior of the pipe wall. Its a bit like a bouncing ball, after every bounce the amplitude gets less.
Mike Crowley thanks a lot proffessor for your answer, so exactly can we calculate that reflection or bounce of water inside the pipe with some equation ?
@@rizkyfarizanfiqri7920 are you asking how to calculate the frequency of the oscillation? For a single pipe system with 1 closed end, the fundamental frequency= acoustic velocity / 2 / pipe length
I am a research scholar working on water hammer analysis in the pipeline. I want to make a test rig for an experiment showing water hammer phenomena in both for rapid and slow valve closure. my operating pressure is 7 Bar. please advise me how to construct my experimental test rig.
Ive done this tests and analysis many times for aerospace applications. Instruments: standard and Piezoelectric pressure transducer, flow meter, valve voltage and current trace, DAQ rate of at least 5000 hz. Other tips: aviod high spots and deadends that could trap gas, perform your analysis before building your test stand, use method of characteristics for analysis. Good luck
The principles of water hammer can be applied to any fluid, whether it be liquid or gaseous. Indeed, if you consider the tuned manifold of an Otto Cycle engine, whether it be intake or exhaust, you'll find that most such "tuned" manifolds take advantage of either the third or fourth "harmonic" of the cycle while the valve is closed. While they were impractical for vehicle installation, Jaguar experimented with intake manifolds "tuned" to the first harmonic and achieved volumetric efficiencies well over one hundred percent. Tuned exhaust manifolds should have cones at the exits to reduce energy loss during reverse flow. WHSHOPE@EARTHLINK.NET
Thanks for this. I only heard of water hammer a fortnight to 1 month ago when it happened at our house. It just happened again today. I looked into it a bit 1 month ago and understood it a bit but I know understand a lot more about it since watching your video. You are really good at explaining it so people can understand exactly what is going on when water hammer happens.
what I can say is I'm so pleased to watch your video Eng. Mike because it made easier the introduction to water hammer. thanks for your time helping me and others
+regis banza Ntombe Thanks for your feed back
nice explanation for water hammer, we just finished covering this in my hydraulics course.
Thank you very much
I have a research problem in a refinery where a sudden closure of a valve caused damage to an expansion joint
I need help to calculate the pressure rise that caused the failure
Install a pressure gauge to detect the pressure of that point. Then you may install a pressure regulating valve prior that point.
A question Mr. Crowley, what about if we have a centrifugal pump working and suddenly somebody shut-off the valve very fast, this shockwave is going to act on the spiral volute of the pump or just inside the pipe.
In my industry we have been facing an unique water hammer problem which has been developed to deliver max 6bar pressure via pump automation.
The logic was to turn off the pump by pressure switch when the pipe pressure reaches 6+ bar. And when the pipe end valve will open and pipe pressure drops below 3bar then the pump will start. Logically its working but we are facing water hammer problem when the pipe end valve shuts. During that phase the pressure wave oscillates violently 0 to 10 bar. It causes to turn on and off the pump via pressure switch.
Point to be noted, there is a non-return valve after pump delivery point and before pressure switches. It happens for few minutes.
I am thinking to place a non-return valve at pressure switch outlet point to control the reverse pressure wave, will it work?
Great lecture, thank you for the amazingly detailed description.
You say in a video that "g" is a gravational constant at 3:35 listen it
Gravational constant and acceleration due to gravity are different.
hello!!!! is it the same study to calculate the pressure that will build up inside a bottle of a ram pump.... is there a video about this? thanks
Air will absorb if not pipe will burst
i want to solve a transient problem in pipelines which is connected in series. three pipes r connected with each other with reducing diameter. this problem is give in the book titled hydraulic transients by streeter and wiley. but i cant able to solve this problem. please help me in this matter.
thanks
I want solution of differential equation of water hammer problem.
before i am very thank full to professor (mike crowley) has posted about water hammer video which very help me cause i am student of mechanical engineering having thesis to analysis of fluid dynamic phenomena concerning on water hammer (creating hydraulic ram pump with harnessing water hammer as main power). But i still confusing about effect of water hammer after it is rising up the pressure causes water having supersonic velocity after the valve closed, my question actually very simple but i still cannot get the answer.
"after water hammer happened, the water's behave always makes reflection cause the valve closed...and how long the reflection of water inside the pipe ?"
Hopefully you can reply my question, that is big favorable to me...
Every cycle the amplitude gets a little bit less due to friction and the inelastic behavior of the pipe wall. Its a bit like a bouncing ball, after every bounce the amplitude gets less.
Mike Crowley thanks a lot proffessor for your answer, so exactly can we calculate that reflection or bounce of water inside the pipe with some equation ?
@@rizkyfarizanfiqri7920 bounce will burst pipe in empty air chamber or absorbed in air chamber
@@rizkyfarizanfiqri7920 are you asking how to calculate the frequency of the oscillation? For a single pipe system with 1 closed end, the fundamental frequency= acoustic velocity / 2 / pipe length
thanks for your easy explain ,many thanks from SYRIA
Thank you very much. Its very good and clear explanation.
I am a research scholar working on water hammer analysis in the pipeline. I want to make a test rig for an experiment showing water hammer phenomena in both for rapid and slow valve closure. my operating pressure is 7 Bar. please advise me how to construct my experimental test rig.
Ive done this tests and analysis many times for aerospace applications. Instruments: standard and Piezoelectric pressure transducer, flow meter, valve voltage and current trace, DAQ rate of at least 5000 hz. Other tips: aviod high spots and deadends that could trap gas, perform your analysis before building your test stand, use method of characteristics for analysis. Good luck
thanks a lot from Egypt
Many thanks from Kenya
great explanation
Thx from Chile!
Thanks from India
Thanks from Thailand
Very helpful, thank you
Thanks from UAE
Thanks from New York city
many thanx from india
g is not gravational constant
It's a acceleration due to gravity
Value of gravational constant is 6.67×10^-11
On the surface of the earth it is relatively constant at 9.81 m/s^2
thanks from spain
who can help me plz
The principles of water hammer can be applied to any fluid, whether it be liquid or gaseous. Indeed, if you consider the tuned manifold of an Otto Cycle engine, whether it be intake or exhaust, you'll find that most such "tuned" manifolds take advantage of either the third or fourth "harmonic" of the cycle while the valve is closed. While they were impractical for vehicle installation, Jaguar experimented with intake manifolds "tuned" to the first harmonic and achieved volumetric efficiencies well over one hundred percent. Tuned exhaust manifolds should have cones at the exits to reduce energy loss during reverse flow. WHSHOPE@EARTHLINK.NET
thanks you for share :D
So speed of sound equalls speed of hammer interesting
TKs from VIetnamese