CFD Modelling and Simulation of Ground Storage Reservoir

Introduction

Ground Storage Reservoirs (GSRs) play a vital role in water supply systems by storing treated water until it is needed for distribution. These reservoirs help balance water supply with demand, ensuring that water is available during peak usage times. Additionally, GSRs help maintain consistent water pressure in the distribution network and provide a buffer during emergencies or maintenance activities. Effective design and operation of GSRs are crucial for ensuring reliable water delivery and maintaining water quality.



Objective

The primary objectives of this CFD analysis are:

  • The objective of the study is to analyze water flow profiles and vortex formation at different heights
  • To evaluate whether the tank achieves plug flow by checking hydraulic efficiency indices and verifying vortex presence, pre-swirl angle, and axial velocity deviation according to ANSI/HI 9.8 guidelines.
  • Advise the client if the provided baffle design can meet the design objective if not provide design suggestions and modifications.

Analysis and Conclusion

  • A 3D geometrical model of the GSR compartment was developed based on the provided 2D drawings. The fluid domain was meshed specifically for CFD simulation.
  • CFD modeling and simulation study was conducted on a Ground Storage Reservoir (GSR) to evaluate flow profiles, residence time distribution (RTD), and vortex formation.
  • The study was carried out for various scenarios and it was observed that there was acceptable plug flow and no significant impact from the surface or submerged vortices. The pre-swirl angle at the outlet was also within the acceptable limits for the scenarios carried out.
  • Overall, the updated baffle arrangement improved flow dynamics met ANSI/HI 9.8 guidelines, and confirmed the GSR’s hydraulic efficiency under both scenarios.