Presenter/Author Information

Sarah Jane Wakes, University of OtagoFollow

Keywords

Snow fences; Computational Fluid Dynamics; turbulence models

Location

Session H6: Environmental Fluid Mechanics - Theoretical, Modeling and Experimental Approaches

Start Date

17-6-2014 2:00 PM

End Date

17-6-2014 3:20 PM

Abstract

The predominant reason for controlling snow deposition using fences is to keep roads and areas around buildings clear of snow during winter months. Empirical guidelines exist but little work has been done optimising fencing design for specific purpose and location. An alternative use of snow fences in New Zealand has been to control the position of drifting snow to simulate changing climatic conditions for plant research over 30 years. This has been of varied success due to lack of design guidelines and the difficulty of gathering field data for snow deposition for validation. Initial work uses Computational Fluid Dynamics (CFD) to gain deeper understanding of the wind flow and snow deposition needed to optimise the fence design. The use of numerical modelling as a tool in the design process relies on understanding the effectiveness of the tool, the level of accuracy required, as well as the relationship between the models used in the simulations and the physics of the specific situation. The relationship between the snow patterns, fence design, turbulence model and wind velocity is explored. Idealised models of a snow fence were simulated using a mixture multiphase model and two turbulence models. The turbulence model was found to make a significant difference in the snow deposition and is an important modelling choice in such simulations for design purposes. CFD is found to be an effective tool in the initial design of snow fences, although more work is needed to optimise the modelling parameters.

 
Jun 17th, 2:00 PM Jun 17th, 3:20 PM

Use of CFD in the initial design of a snow fence

Session H6: Environmental Fluid Mechanics - Theoretical, Modeling and Experimental Approaches

The predominant reason for controlling snow deposition using fences is to keep roads and areas around buildings clear of snow during winter months. Empirical guidelines exist but little work has been done optimising fencing design for specific purpose and location. An alternative use of snow fences in New Zealand has been to control the position of drifting snow to simulate changing climatic conditions for plant research over 30 years. This has been of varied success due to lack of design guidelines and the difficulty of gathering field data for snow deposition for validation. Initial work uses Computational Fluid Dynamics (CFD) to gain deeper understanding of the wind flow and snow deposition needed to optimise the fence design. The use of numerical modelling as a tool in the design process relies on understanding the effectiveness of the tool, the level of accuracy required, as well as the relationship between the models used in the simulations and the physics of the specific situation. The relationship between the snow patterns, fence design, turbulence model and wind velocity is explored. Idealised models of a snow fence were simulated using a mixture multiphase model and two turbulence models. The turbulence model was found to make a significant difference in the snow deposition and is an important modelling choice in such simulations for design purposes. CFD is found to be an effective tool in the initial design of snow fences, although more work is needed to optimise the modelling parameters.