Wind and Structures

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Wind flow modification by a jet roof for mitigation of snow cornice formation

  • Kumar, Ganesh (Defence Geo-Informatics Research Establishment, Defence Research and Development Organization) ;
  • Gairola, Ajay (Civil Engineering Department, Indian Institute of Technology) ;
  • Vaid, Aditya (Defence Geo-Informatics Research Establishment, Defence Research and Development Organization)
  • Received : 2019.07.03
  • Accepted : 2021.02.05
  • Published : 2021.02.25
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Abstract

The snow cornice mass on the formation zone had triggered avalanches which led to the loss of human life and property. Snow cornice is formed due to flow separation on the leeward side. Effect of lee slope is more prominent in the formation of snow cornices as compared to the windward slope. The analysis of wind flow pattern has been carried out to evaluate the performance of a jet roof. Computational Fluid Dynamics (CFD) analysis of wind flow over a 2D hill model was carried out using RNG based k-∈ turbulence models available in ANSYS Fluent. Effect of varying leeward hill slope (1:2 to 1:6) on flow separation for the given windward slope was observed and a critical slope of 1:4 was found at which the separation zone ceased to exist. The modification of wind flow over a hill due to the installation of jet roof was simulated. It was observed that jet roof had significantly modified the wind flow pattern around hill ridgeline and ultimately snow cornice formation had mitigated. The results of the wind flow pattern were validated with the wind data collected at the experimental site, Banihal Top (Jammu and Kashmir, India). The wind flow simulation over the hill and mitigation of cornice formation by the jet roof has been explained in the present paper.

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References

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