changes.mady.by.user Arthur Aslanyan (Nafta College)
Saved on Nov 25, 2019
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{\rm Nu}=3.66 + \frac{ 0.065 \cdot {\rm Re} \cdot {\rm Pr} \cdot {D/L} }{ 1 + 0.04 \cdot ({\rm Re} \cdot {\rm Pr} \cdot {D/L})^{2/3} }
Laminar flow in pipeline with diameter
{\rm Nu}=\frac{ (f/8) \, ({\rm Re} - 1000) {\rm Pr} }{ 1 + 12.7 \, (f/8)^{1/2} \, ({\rm Pr}^{2/3} -1) }
Gnielinski
Laminar-turbulent transition and turbulent flow in pipeline
{\rm Nu}=0.3 + \frac{0.62 \, \mbox{Re}^{1/2} \, \mbox{Pr}^{1/3} } {\left[ 1+ (0.4/\mbox{Pr})^{2/3} \right]^{1/4}} \left[ 1 + \left( \frac{\mbox{Re}}{282000} \right)^{5/8}\right]^{4/5}
Churchill–Bernstein
Accuracy