thank you so much. could you please tell me what relations between laminar , turbulent , developing and fully developed flow? it is must be turbulent flow to be fully developed ? and laminar to be developing ?
Absolutely, in fact there are papers that demonstrate laminar flow at Re>100,000 for highly idealised systems! This is very much an introductory level treatment of the subject. There are many more levels of complexity on top of this (especially given that there is still no full theory of turbulence yet).
Yep! Apparently Reynolds experiment was once retested and the transition values were different. Initially it was a mystery, then it was realised that the values had changed due to vibrations from modern day traffic (the lab was under a road).
Thanks for the comment. Yes that's correct, but there are two ways to write the equation. Reynolds number is (density* diameter* mean velocity)/(dynamic viscosity), which is the same thing as the equation I was using which is (diameter* mean velocity)/(kinematic viscosity) as kinematic viscosity is defined as dynamic viscosity/density.
First for laminar flow which is parabolic continuity rule of flow rate cannot be applied in parabolic laminar flow maximum velocity is in center and zero at surface of channel. That is first indicator laminar and turbulent is invalid definition together with Re number. Second perform experiment in transparent tube with potassium permanganate which dissolves in water and with inject printer ink which very fine particles, but still are 100 times bigger than water molecules but you see that at Re
Check out new content on this channel about the flume I built in my office:
th-cam.com/video/sppaBqpIT-w/w-d-xo.html
Good explanation for people with pre-requisite knowledge
The video is really helpful and easy to understand, great job thank you sir 🙏
Thanks! I also have more recent videos on this topic!
Great explanation. Thanks
Many thanks!
Really excellent. Thank you.
thank you so much. could you please tell me what relations between laminar , turbulent , developing and fully developed flow? it is must be turbulent flow to be fully developed ? and laminar to be developing ?
It's the science of how fluids relate to their environment. Maybe they should teach a class on fluid psychology.
School tryna taste my loyalty 😂😂
Re
Absolutely, in fact there are papers that demonstrate laminar flow at Re>100,000 for highly idealised systems! This is very much an introductory level treatment of the subject. There are many more levels of complexity on top of this (especially given that there is still no full theory of turbulence yet).
@@fluidsexplained1901 is there an analogy between turbulent flow and non ideal gas models like van Der waals?
really helpful
How critical velocity proportional with radius?
So the fluid becomes a victim of disorderly conduct when a guy hits the pipe then?
Yep! Apparently Reynolds experiment was once retested and the transition values were different. Initially it was a mystery, then it was realised that the values had changed due to vibrations from modern day traffic (the lab was under a road).
@@fluidsexplained1901 other experiments about electricity and magnetism have been disrupted by power lines.
great video but is the reynolds equation not (density* diameter* mean velocitiy)/(viscosity)
Thanks for the comment. Yes that's correct, but there are two ways to write the equation. Reynolds number is (density* diameter* mean velocity)/(dynamic viscosity), which is the same thing as the equation I was using which is (diameter* mean velocity)/(kinematic viscosity) as kinematic viscosity is defined as dynamic viscosity/density.
I’ve now re-made this video with real models:
th-cam.com/video/vhDaCZZ0Sc4/w-d-xo.html
does the reynolds number equation still apply if the object is moving through a stationary fluid?
Yep! But the length-scale will be the size of the object rather than the pipe diameter.
do we have an email we can contact you on??
*Do you
First for laminar flow which is parabolic continuity rule of flow rate cannot be applied in parabolic laminar flow maximum velocity is in center and zero at surface of channel. That is first indicator laminar and turbulent is invalid definition together with Re number. Second perform experiment in transparent tube with potassium permanganate which dissolves in water and with inject printer ink which very fine particles, but still are 100 times bigger than water molecules but you see that at Re
sbbed
Good video but boring presenting tone. Fell asleep mid way
I have an improved video on laminar flow, but unfortunately I still have the same voice 😉
th-cam.com/video/vhDaCZZ0Sc4/w-d-xo.html