Numerical simulation of three-dimensional velocity fields in pressurized and non-pressurized Nye channels

PD Bates*, MJ Siegert, V Lee, BP Hubbard, PW Nienow

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference Contribution (Conference Proceeding)

Abstract

Channels incised into bedrock, or Nye channels, of tell form an important component of subglacial drainage at temperate glaciers, and their structure exerts control over patterns and rates of (a) channel erosion, (b) water flow-velocity and (c) water pressure. The latter, in turn, exerts a strong control over basal traction and, thus, ice dynamics. In order to investigate these controls, it is necessary to quantify detailed flow processes in subglacial Nye channels. However, it is effectively impossible to acquire such measurements from fully pressurized, subglacial channels. To solve this problem, we here apply a three-dimensional, finite-volume solution of the Reynolds averaged Navier-Stokes (RANS) equations with a one-equation mixing-length turbulence closure to simulate flow in a 3 in long section of an active Nye channel located in the immediate foreground of Glacier de Tsanfleuron, Switzerland. Numerical model output permits high-resolution visualization of water flow through the channel reach, and enables evaluation of the experimental manipulation of the pressure field adopted across the overlying ice lid. This yields an increased theoretical understanding of the hydraulic behaviour of Nye channels, and, in the future, of their effect on glacier drainage, geomorphology and ice dynamics.

Original languageEnglish
Title of host publicationANNALS OF GLACIOLOGY, VOL 37
EditorsP Duval
Place of PublicationCAMBRIDGE
PublisherINT GLACIOLOGICAL SOC
Pages281-285
Number of pages5
ISBN (Print)0-946417-32-6
Publication statusPublished - 2003
EventInternational Symposium on Physical and Mechanical Processes om Ice in Relation to Glacier and Ice-Sheet Modelling - Chamonix, France
Duration: 25 Aug 200230 Aug 2002

Publication series

NameANNALS OF GLACIOLOGY
PublisherINT GLACIOLOGICAL SOC
Volume37
ISSN (Print)0260-3055

Conference

ConferenceInternational Symposium on Physical and Mechanical Processes om Ice in Relation to Glacier and Ice-Sheet Modelling
CountryFrance
CityChamonix
Period25/08/0230/08/02

Keywords

  • GLACIER
  • ROUGHNESS
  • COMPUTATIONAL FLUID-DYNAMICS
  • RIVER

Cite this