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View Full Version : Q about PEDs>>> I need some help


thepioneerm
Apr29-09, 09:38 AM
Please:


http://www.physicsforums.com/attachment.php?attachmentid=18691&stc=1&d=1241015698

coomast
Apr29-09, 01:22 PM
I had a look at it and after a few minutes I got a transformed result, but indeed it is not the one given. However there seems to be a term missing in the left hand side containing the time t. After using the transformation I got (without the term with the time):

u^*\frac{\partial u^*}{\partial x^*}+ v^*\frac{\partial u^*}{\partial y^*}= m\cdot \frac{U^{n-1}}{L^n}\cdot \left[M\cdot \theta + \frac{\partial}{\partial y^*} \left[\left|\frac{\partial u^*}{\partial y^*}\right| ^{n-1} \right]\cdot \frac{\partial u^*}{\partial y^*}\right]

Maybe the term with t can shed some light on the necessary next step, otherwise I do not see how to reach the end result.

coomast

thepioneerm
Apr29-09, 02:11 PM
coomast

thank you very much

but how do you reach this result ??!!!

please can you explain it to me

even I don't know how to get

http://www.physicsforums.com/attachment.php?attachmentid=18694&stc=1&d=1241032119

coomast
May4-09, 01:20 PM
coomast

thank you very much

but how do you reach this result ??!!!

please can you explain it to me

even I don't know how to get




pfff.....the preview gives a different formula then the one I'm typing, I assume the latex is still broken


This is done in the same way as before, you have:

v\frac{\partial u}{\partial y}=v^*U\frac{\partial u^*U}{\partial y^*L} = \frac{U^2}{L} v^*\frac{\partial u^*}{\partial y^*}

After doing this to the other terms as well, you end up with the result I gave earlier. Beware of the error in the question, you will not be able to reach the solution given.

remark 1: sorry for the late reply, I had a busy week
remark 2: don't use a font this big, it looks as if you are shouting which is not the intention I suppose, instead look at learning the basics of latex, it will be helpfull in producing the nice formula's out here :-) [if the bloody thing works, lol]

seems the latex is OK after all.... this does not follow a mathematical rule, perhaps something chaotic...could be me as well...

best regards,

coomast

thepioneerm
May4-09, 02:23 PM
coomast

thank thank thank you very very very much

and I will not use a font this big ^-^

and I will try to learn the basics of latex

thank you