CFD Study and Investigation of the Critical Ratio for Pressure-Head Ratio inside Drainage Manholes


  • Sifa Yohana Baseka Nelson Mandela African Institution of Science and Technology, Tanzania
  • Verdiana Grace Masanja The Nelson Mandela African Institution of Science and Technology , Tanzania



Manhole to Pipe Ratio, Sewage Water, Manhole Overflow


The objective of this research is to study the pressure-head rising inside a manhole in pipelines, in relationship with the ratio from manhole diameters to its pipes diameters. The research team adopted CFD to simulate the manhole flows, at different conditions of varying inlet and outlet pipes diameter and manhole diameters. The risk of manhole overflow can also be reduced by controlling how fast is the rate of pressure-head rise per given flow rate. To reduce the peak and rate of rising of pressure-head column inside the manhole to be attained, the ratio between manhole widths (diameter) to its pipe diameter should be taken into considerations. Based on CFD analysis it is found that ratios less than 3 are shown to have better results, producing lower peak values of pressure-head to be attained inside manholes.


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How to Cite

Sifa Yohana Baseka, & Verdiana Grace Masanja. (2022). CFD Study and Investigation of the Critical Ratio for Pressure-Head Ratio inside Drainage Manholes. International Journal of Advances in Scientific Research and Engineering (IJASRE), ISSN:2454-8006, DOI: 10.31695/IJASRE, 8(1), 52–58.