Fluid Mechanics Questions & Answers  


Yes, you can assume that $f$ is constant for a Reynolds number higher than $10^8$ for the range of $e/D$ shown on the right axis of the Moody diagram. I think this is kind of obvious from the figure.. So I'll give you just 1 point bonus boost for your question.


 Bonus boost added to the scoresheet




This is a good observation. But, the drawing on the board was meant as a schematic to give a rough idea of how the system looks like. The schematic is not meant to say that there are 4 bends at 90 degrees and a fifth at 45 degrees. It is meant to say there are 5 bends. Exactly what the turning angle is for each bend is not known — all we know is the loss coefficient. I'll give you 1.5 points bonus boost for your question.




Hmm, you can not use a figure this way. Figures are reserved for drawings and schematics, and shouldn't be used for mathematics. Use LATEX to typeset the mathematics and get rid of the figure. Then I'll answer your question.


OK, I see you edited your post and I will answer your question. The terms proportional to $1/R^2$ are those where there is a second derivative with respect to $r$ or those proportional to $1/r^2$. Likewise, the terms with a second derivative with respect to $z$ scale with $1/H^2$. I think I explained this in class already, so I'll give you just 1 point bonus boost for your question.





$\pi$ 