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Old   December 16, 2009, 10:14
Default a simple differential operation question
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Pei-Ying Hsieh
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Dear CFD experts,

Can someone post websites that shows differential operations in cartesian/cylindrical coordinates?

What I am looking for specifcally is

grad(H^2), where H is a vector field. Thanks!

phsieh
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Old   December 17, 2009, 12:52
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Any classical Fluid Mechanics book should have the expression for gradient, divergence and rotor in cartesian, cylindrical and spherical coordinates.

Check for example the book of White - Fluid Mechanics

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Old   December 20, 2009, 13:27
Default del differential operator
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Hi,

Thanks for the reply! I do not have White handy. But, could not find what I am looking for in other Fluid Mechanics textbooks or internet.

Actually, what I am actually looking for is:

del (H^2), where H is a vector field and del is nabla. How do I write out the differential operation in Cartesian Coordinates?

Can someone help?

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Old   December 20, 2009, 23:44
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Or ... you can try Google (it generally works):

http://en.wikipedia.org/wiki/Del_in_...al_coordinates

Here you have all your operators gradient, rotor and divergence in Cartesian, Cylindrical and Spherical coordinates.
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Old   December 20, 2009, 23:53
Default Gradient rule
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Probably what you are looking for is:

\nablafg=f\nablag + g\nablaf

where you will use f=v and g=v.
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Old   December 21, 2009, 08:36
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Hi, DoHander,

Thanks!

phsieh2005
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