Comparison of Maximum Allowable Pump Speed in a Horizontal and Vertical Pipe of Equal Geometry at Constant Power

D. Bashar, A. Usman, M. K. Aliyu, D. S. Yawas


This work determines and compares the maximum possible velocity fluids can be transported through a vertical and horizontal pipe of the same geometry at constant pump power. The analysis involves simulation of theoretical piping equations, analysis of the pumping, frictional and static pressure with respect to flow velocity using MS excel and Matlab. Computational results obtained from MS excel and represented graphically in Matlab establishes the maximum allowable velocity – below which the fluid can be transported safely within the required flow input conditions (i.e. diameter, length and pump power) and above which it will be impossible for the fluid to be pumped to the given height or length under the same flow conditions. It was also found that the maximum allowable velocity is always greater in a horizontal pipe than in a vertical pipe but with pumping pressure higher in the later. In addition, a general equation was determined for approximate determination of the maximum fluid velocity given pipe length (height), pump power and pipe diameter.

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