Correction: At 16:40 Sec, ratio of two frequencies should be greater than sq(2), instead of less than sq(2). I wrote it wrongly. please correct. for Tr less than unity, ratio r (omega/omega_n) should be more than sq(2).
When explaining about the transmissibility curve you have mentioned as the r value increases, the transmissibilty ratio decreases(physical meaning lesser vibration transfer). And around the end of the session during explanation with the example you have told the T.R and r relation effect in vice-versa.
At 16:40 Sec, ratio of two frequencies should be greater than sq(2), instead of less than sq(2). I wrote it wrongly. please correct. for Tr less than unity, ratio r (omega/omega_n) should be more than sq(2).
derive the expression for displacement transmissibility for a single degree of freedom spring mass-dashpot system subjected to the excitation of base. plot the displacement transmissibility ratio for different amounts of damping against the frequency ratio
Dear Mr. Kumar, thank you for pointing out it, you are correct. I also observed it some days ago but not able to edit as you tube does not has some means to do so.
I am trying to add some comment at that instance or otherwise I will add a public comment here. Plz suggest If you know some means to put a comment on screen at that instance.
I donno how to do it, but I've seen corrections pop up at the top right corner from "i" symbol, at that instant of time. I found your content concise and intresting than NPTEL.
Hemanth Siva Kumar : Thank you for kind appreciation...I am also preparing vibration of continuous system and other advance topics...I will try my best to make thosw content.
Hello Ashish , I need your help for a vibration problem related with a machine . This machine is mounted on structure . Shaft of machine is vertical & unbalanced force act perpendicular to machine. Damping pad are provided below machine part . As force is horizontal - Fo sinwt & damping is vertically downwards . How to reduce the vibration of machine .
Hello Kiran, First let me repeat what I have understood from your query, there is a machine with vertical shaft, unbalance forces will be in horizontal plane, and thus the excitation will act in horizontal plane which is perpendicular to the axis of shaft. The damping pad is mounted below the machine ( I am correct?) the the machine is vibrating. Is it vibrating along vertical axis or in some different mode? Is the machine is free from the top side OR has some constrains. I guess, if it has free end type boundary at the top side, the vibration may be like transverse vibration of a pole fixed from the base. since the base has damper( rubber mounts ?) It may have vibrations there may be several reason, I can answer properly if you can share a picture or a rough diagram. My mail id is ashishpurohit1@gmail.com. Further queries are most welcomed. Plz feel free to ask any question regarding your problem.
Your understanding is correct. Damping pads are mounted below machine.Machine outer body is cylindrical . Vibrations are observed on circumference & on Top of Machine (Top Plate ) & on structure also. Vibration at any particular point is constant. Machine is free from top. Base dampers are rubber mounts (Cylindrical) . I will mail you with proper diagram. Thanks! Kiran.
in such case, addition of a dynamic vibration absorber will serve the purpose, if you can measure frequency of the vibration, you can design an absorber, which will absorb vibration of machine. If you want further details of an absorber, plz see video or I can help you if you wish.
Hi ashish very nice video. I have a problem please I need your help on the demonstration of the transmisibility concept but for a relative displacement . it would be very helpful if you can show me how. greetings from Peru :)
Dear Ro ven thank you for query...in case of explanation of transmissibility with relative motion..A vehicle on uneven road is the best example..If you are expecting a different answers..please share your mail ID ..we will discuss with pictorial way.
@@ashishpurohit9138 hellow thanks for answer me. I am investigating about base isolation and the use of relative transmisibility for my degree I would like to contact you for a specific discussion. My email is rodrigovente@gmail.com
Hi, Thanks for your query. As per my presentation, it will be 1 as it is the ratio of two forces. However, as per S S Rao, it will be zero. Nevertheless, it will not affect the results. I have taken generalized definition of transmissibility (from FUNDAMENTALS OF VIBRATIONS Leonard Meirovitch).
Hi, I have checked the formula showing F_t/kY=r^2(sqrt(............), if you have doubt between what I showed in my video and what is given in Rao, Actually both are same. actually some books says TR is just F_t/F_o, Prof. Rao has slightly different presentation.
Correction: At 16:40 Sec, ratio of two frequencies should be greater than sq(2), instead of less than sq(2). I wrote it wrongly. please correct. for Tr less than unity, ratio r (omega/omega_n) should be more than sq(2).
sir,
requesting you to please pin this comment.
and a lot of thanks to you sir for this lecture and I appreciate your efforts.
Great amd wonderful explanation, keep the good work
Quick and clear explanation! Thanks
Thank you very much
1 - 1 - 2023
1 January 2023 - Me 413 Final tonight at 7:00 P.M. in B54
This video is excellent! Much better than my professor!
Thank you
Thank you so much for making it so easy to understand cheers!!
You are the man, great explanation buddy.
yesssiiirrrrrrrr
When explaining about the transmissibility curve you have mentioned as the r value increases, the transmissibilty ratio decreases(physical meaning lesser vibration transfer).
And around the end of the session during explanation with the example you have told the T.R and r relation effect in vice-versa.
At 16:40 Sec, ratio of two frequencies should be greater than sq(2), instead of less than sq(2). I wrote it wrongly. please correct. for Tr less than unity, ratio r (omega/omega_n) should be more than sq(2).
is your doubt is the explanation at 16:40 sec.? please clarify..
Thank you brother. Keep uploading such videos in future too.
sum boi appreciate it my guy
Excellent video!
derive the expression for displacement transmissibility for a single degree of freedom spring mass-dashpot system subjected to the excitation of base. plot the displacement transmissibility ratio for different amounts of damping against the frequency ratio
@ 16:40 w/w(n) > root 2
Dear Mr. Kumar, thank you for pointing out it, you are correct. I also observed it some days ago but not able to edit as you tube does not has some means to do so.
I am trying to add some comment at that instance or otherwise I will add a public comment here. Plz suggest If you know some means to put a comment on screen at that instance.
I donno how to do it, but I've seen corrections pop up at the top right corner from "i" symbol, at that instant of time.
I found your content concise and intresting than NPTEL.
Hemanth Siva Kumar : Thank you for kind appreciation...I am also preparing vibration of continuous system and other advance topics...I will try my best to make thosw content.
Hello Ashish ,
I need your help for a vibration problem related with a machine . This machine is mounted on structure . Shaft of machine is vertical & unbalanced force act perpendicular to machine. Damping pad are provided below machine part .
As force is horizontal - Fo sinwt & damping is vertically downwards . How to reduce the vibration of machine .
Hello Kiran, First let me repeat what I have understood from your query, there is a machine with vertical shaft, unbalance forces will be in horizontal plane, and thus the excitation will act in horizontal plane which is perpendicular to the axis of shaft. The damping pad is mounted below the machine ( I am correct?) the the machine is vibrating. Is it vibrating along vertical axis or in some different mode?
Is the machine is free from the top side OR has some constrains. I guess, if it has free end type boundary at the top side, the vibration may be like transverse vibration of a pole fixed from the base. since the base has damper( rubber mounts ?) It may have vibrations
there may be several reason, I can answer properly if you can share a picture or a rough diagram. My mail id is ashishpurohit1@gmail.com. Further queries are most welcomed. Plz feel free to ask any question regarding your problem.
Your understanding is correct.
Damping pads are mounted below machine.Machine outer body is cylindrical . Vibrations are observed on circumference & on Top of Machine (Top Plate ) & on structure also. Vibration at any particular point is constant.
Machine is free from top. Base dampers are rubber mounts (Cylindrical) . I will mail you with proper diagram.
Thanks!
Kiran.
in such case, addition of a dynamic vibration absorber will serve the purpose, if you can measure frequency of the vibration, you can design an absorber, which will absorb vibration of machine. If you want further details of an absorber, plz see video or I can help you if you wish.
+Ashish Purohit , pls.check mail you sent to you.
+Ashish Purohit ,pls.check mail
vary good sir thankyou
Thank you
Sir motion transmissibility and displacement transmissibility are same????🙏 Plz tell
Yes
@@ashishpurohit9138 thank you ❤️
derive an expression for amplitude and phase angle vibration because of rotating unbalance???........sir can you explain this question 🙏❤️
SIR PLEASSEEEEEEE CONTINUE YOUR LECTURE SERIES ON VIBRATION
PLSSSSS
There is entire series on vibration..butcthat is up to mdof..ifcyou arw looking for continuous system..soon I will upload
Yes Sir Please do that. Thank you sooo much! Glad that I found your channel !! Your lecture is very clearcut and to the point I must say.
Very clearly explained
Thank you Mr Usmani
Rotation speed should be in RPM not in Hz. If F is 50 Hz then Omega should be 2 x pi x F.
cool!!! thank u :)
thank you
splendid tho
Hi ashish
very nice video.
I have a problem please I need your help on the demonstration of the transmisibility concept but for a relative displacement . it would be very helpful if you can show me how.
greetings from Peru :)
Dear Ro ven thank you for query...in case of explanation of transmissibility with relative motion..A vehicle on uneven road is the best example..If you are expecting a different answers..please share your mail ID ..we will discuss with pictorial way.
@@ashishpurohit9138 hellow thanks for answer me. I am investigating about base isolation and the use of relative transmisibility for my degree I would like to contact you for a specific discussion. My email is rodrigovente@gmail.com
if r=0 , can Force transmissibility be 1 , pls check?
Hi, Thanks for your query.
As per my presentation, it will be 1 as it is the ratio of two forces. However, as per S S Rao, it will be zero. Nevertheless, it will not affect the results. I have taken generalized definition of transmissibility (from FUNDAMENTALS OF VIBRATIONS Leonard Meirovitch).
pls check force transmissibility formula from SS Rao, mechanical vibrations, pg no 271, edition 4
Hi, I have checked the formula showing F_t/kY=r^2(sqrt(............), if you have doubt between what I showed in my video and what is given in Rao, Actually both are same. actually some books says TR is just F_t/F_o, Prof. Rao has slightly different presentation.
@@ashishpurohit9138 as per SS Rao force Transmissibility graph starts from Zero for r=0 . Please clarify.
@@25parthy Because in Rao's formula, r^2 is taken al the RHS, hence ar r=0, LHS become zero and graph starts from zero.
🤗🤗🤗🤗🤗