Transformation of Reynolds Equation from Cartesian to cylindrical

AI Thread Summary
The discussion focuses on transforming the Reynolds Equation from Cartesian to cylindrical coordinates, highlighting the mathematical expressions involved. The original equation is presented in Cartesian form, followed by its cylindrical counterpart, emphasizing the need for careful conversion. Participants suggest reviewing the steps taken in the Cartesian derivation before attempting the cylindrical transformation to ensure accuracy. This approach is recommended as a systematic way to tackle the problem. Understanding these transformations is crucial for fluid dynamics applications in cylindrical geometries.
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How to convert the Reynolds equation from Cartesian coordinate (equation1) to cylindrical coordinate (equation2)? by showing the steps?
∂/∂x ((ρh^3)/12μ ∂p/∂x) + ∂/∂z ((ρh^3)/12μ ∂p/∂z) = ∂/∂x (ρh (U_1+U_2)/2) + ∂/∂z (ρh (W_1+W_2)/2) + (∂(ρh))/∂t (1)

1/r ∂/∂r (r (ρh^3)/12μ ∂p/∂r) + 1/r ∂/∂θ ((ρh^3)/12μ ∂p/r∂θ) = rω/2 ∂(ρh)/r∂θ + (∂(ρh))/∂t (2)
 
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Rather than attempt a conversion, why not review the steps in the Cartesian derivation, and then attempt to repeat the equivalent steps in cylindrical coordinates? I think that is the way I would approach this problem.
 
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