Cauchy's equation in terms of material acceleration

AI Thread Summary
The discussion focuses on transforming Cauchy's equation in terms of material acceleration, specifically addressing the right-hand side of the equation involving the dot product of del and the second-order tensor (rho*V V). Participants emphasize that the problem involves applying the derivative of a product rule in vector contexts. A suggested approach to verify the identity is to express it in Cartesian component form. The conversation highlights the importance of understanding vector calculus in this context. Overall, the thread aims to clarify the mathematical formulation related to material acceleration in fluid dynamics.
Adam Venter
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Does anyone know which formula is used or how to arrive at the righthand side of the equation below, which is the dot product of del and rho*a 2nd order tensor(V V).
. represents dot product
and X a vector quantity
This problem is in connection with transforming cauchy's equation in terms of the material acceleration

del . (rho*V V) = {V*del . (rho*V) } + {rho*(V . del)*V}

Thanks
 
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Adam Venter said:
Does anyone know which formula is used or how to arrive at the righthand side of the equation below, which is the dot product of del and rho*a 2nd order tensor(V V).
. represents dot product
and X a vector quantity
This problem is in connection with transforming cauchy's equation in terms of the material acceleration

del . (rho*V V) = {V*del . (rho*V) } + {rho*(V . del)*V}

Thanks
It's basically application of the derivative of a product rule in a situation in which you are dealing with vectors. The easiest way to prove to yourself that the identity is correct is to write it out in cartesian component form.

Chet
 
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Chestermiller said:
It's basically application of the derivative of a product rule in a situation in which you are dealing with vectors. The easiest way to prove to yourself that the identity is correct is to write it out in cartesian component form.

Chet
Thanks will give that a go
 
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