Call number:
ZSP-201-86/3
In:
CRREL Report, 86-3
Description / Table of Contents:
Experiments to study the melting of a horizontal ice sheet with a flow of water above it were conducted in a 35 m long refrigerated flume with a cross section of 1.2x1.2 m. Water depth, temperature, and velocity were varied as well as the temperature and initial surface profile of the ice sheet. The heat transfer regimes were found to consist of forced turbulent flow at high Reynolds numbers with a transition to free convection heat transfer. There was no convincing evidence of a forced laminar regime. The data were correlated for each of the regimes, with the Reynolds number, Re, or the Grashof number combined with the Reynolds number as Gr/Re to the 2.5 power used to characterize the different kinds of heat transfer. For water flowing over a horizontal ice sheet, the melting heat flux, for low flow velocities, was not found to drop below the value for the free convection case-488.5 W/sq m-as long as the water temperature exceeds 3.4 C. This is significant since the free convection melt values far exceed those for laminar forced convection. At the low flow velocities, the melting flux was not dependent upon the fluid temperature until the water temperature dropped below 3.4 C, when q sub c = 135.7 (Delta T). In general, the heat transfer was found to significantly exceed that of non-melting systems for the same regimes. This was attributed to increased free stream turbulence, thermal instability due to the density maximum of water near 4 C, and the turbulent eddies associated with the generation of a wavy ice surface during the melting.
Type of Medium:
Series available for loan
Pages:
vii, 85 Seiten
,
Illustrationen
Series Statement:
CRREL Report 86-3
URL:
https://apps.dtic.mil/docs/citations/ADA170427
URL:
https://erdc-library.erdc.dren.mil/jspui/bitstream/11681/9438/1/CR-86-3.pdf
Language:
English
Note:
CONTENTS
Abstract
Preface
Nomenclature
Introduction
Non-melting heat transfer relations for horizontal surfaces
Heat transfer for melting horizontal ice sheets
Instrument setup, data acquisition and test procedures
General
Instrumentation
Data acquisition
Computer software
Test procedures
Data output from computer
Equations used for data analysis
Control volume and melting surface
Control of variables
Error analysis
Experimental results and discussion
Wave formation
Temperature and velocity profiles in open channel flow
Correlation of data
Summary
Literature cited
Appendix A: Conversion equations for data acquisition equipment
Appendix B: Computer code for data acquisition and analysis
Appendix C: Typical test output
Appendix D: Thermal properties of water and ice
Appendix E: Error analysis
Appendix F: Summary of test conditions
Appendix G: Experimental data and calculated quantities, with inlet length
Location:
AWI Archive
Branch Library:
AWI Library
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