Forced Flow of Fluids through Tubes Conduits

Forced Flow of Fluids Through Tubes (Conduits) 

For the individual (film) coefficient h for heating or cooling of fluids, without phase change, in turbulent flow through circular tubes, the following dimensionless 

The film coefficient h for turbulent flow of water through a tube can be estimated by the following dimensional equation [1]  

Flow through tubes is sometimes laminar, when fluid viscosity is very high or the conduit diameter is very small, as in the case of hollow fibers. The values of h for laminar flow through tubes can be predicted by the following dimensionless equation [1, 3]  

Equations 5.8 and 5.9 give h for straight tubes. It is known that the values of h for fluids flowing through coils increase somewhat with decreasing radius of helix. However, in practice the values of h for straight tubes can be used in this situation. 

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