Hi Professor, first of all, thank you for all these series, its definitely best on youtube 2- Can you please make video with solving questions about the topics that discussed, that will be awesome, thanks a lot again
"irrotationality implies viscosity" I have a doubt here. If the flow is irrotational, then vorticity is zero, meaning the gradients cancel each other or there are no gradients at all. In the case, where the gradients exist, but cancel each other as explained in 4:53, the viscous force need not be zero. Because the gradients exist. But the flow is irrotational because they cancel each other. So we cannot say irrotational flow always means inviscid flow, Isn't it?
Hi and sorry for the late reply! The semester got a way from me. Not sure I fully understand the comment, a main statement in this video (towards the end, unless I'm missing something) does say that irrotational flow implies inviscid. I'd like to help, can you clarify?
Good evening professor. I don't know if you intend on making more videos or not, but if you wouldn't mind to use either a smaller pen diameter or slightly more penmanship it would make differentiating some of your variables a bit easier. Love the lectures.
Hi! In this case, I don't think so. What we're doing is taking the average angular velocity of each component, where the definition of a mean is (1/n)*sum(x_1:n). So, you will notice shortly before 11:53, omega_z = 0.5*(angular velocity_1 + angular velocity_2). At 11:53, we've just put all three components together and then pulled the 1/2 out front.
Hey Rahul, this one is tough to explain through a comment. Maybe it's helpful to think about the extremes. In the case where both angles are the same, that indicates rigid body rotation and the angular velocity of the element is the same as the sides. If the angle change is equal and opposite, the particle deforms and doesn't rotate (the average is zero). Not sure if I helped or made it worse!
![Bernuolli and Laplace [Aerodynamics #8]](http://i.ytimg.com/vi/1dieMQe23N0/mqdefault.jpg)
![Bernuolli and Laplace [Aerodynamics #8]](/img/tr.png)
![Streamlines and stream function [Aerodynamics #6]](http://i.ytimg.com/vi/LWpSGsOYxPI/mqdefault.jpg)
You are an amazing teacher God Bless You !!!
mixing humor and education... i really got it, thanks to you!
I'm glad you got it!
Glad to find this series, been a great help. thank you!
happy to help!
i never had so clear understanding..........thanks thanks thanks a lot
Awesome!
Brother you are the GOAT thank you
Thanks!!
Badi maar marenge tumko, Tu hai kon re
Thanks alot..your video is the best
Simple and clear
Thank you!!
Hi Professor, first of all, thank you for all these series, its definitely best on youtube
2- Can you please make video with solving questions about the topics that discussed, that will be awesome, thanks a lot again
Definitely something to consider moving forward, thanks!!
Hi professor
Thanks for your series videos 🙂
18:41
I'm confused. If it needs to add minus to grad stream function for v velocity at y direction?
Hello! I'm afraid I don't follow the question, could you perhaps reword it?
Thank you sir , may God bless you 🙏
Thanks!
Great explanation. Thanks
Glad you liked it!
Thanks, Sir, cleared my concepts
Thanks, glad to help!
"irrotationality implies viscosity" I have a doubt here. If the flow is irrotational, then vorticity is zero, meaning the gradients cancel each other or there are no gradients at all. In the case, where the gradients exist, but cancel each other as explained in 4:53, the viscous force need not be zero. Because the gradients exist. But the flow is irrotational because they cancel each other. So we cannot say irrotational flow always means inviscid flow, Isn't it?
Hi and sorry for the late reply! The semester got a way from me.
Not sure I fully understand the comment, a main statement in this video (towards the end, unless I'm missing something) does say that irrotational flow implies inviscid. I'd like to help, can you clarify?
Amazing 👍👍
Thanks!!
Good evening professor. I don't know if you intend on making more videos or not, but if you wouldn't mind to use either a smaller pen diameter or slightly more penmanship it would make differentiating some of your variables a bit easier. Love the lectures.
Thanks! Definitely will try and be more careful in the future, unfortunately my handwriting has always been terrible.
Hi, in 11:53, average angular velocity should be written in (1/3)*(.......) , doesn't it?
Hi! In this case, I don't think so. What we're doing is taking the average angular velocity of each component, where the definition of a mean is (1/n)*sum(x_1:n). So, you will notice shortly before 11:53, omega_z = 0.5*(angular velocity_1 + angular velocity_2). At 11:53, we've just put all three components together and then pulled the 1/2 out front.
sir I have a doubt why is the angular velocity the average of both the rate of change of angles
?
Hey Rahul, this one is tough to explain through a comment. Maybe it's helpful to think about the extremes. In the case where both angles are the same, that indicates rigid body rotation and the angular velocity of the element is the same as the sides. If the angle change is equal and opposite, the particle deforms and doesn't rotate (the average is zero).
Not sure if I helped or made it worse!