UID:
kobvindex_GFZ20190724150404
Format:
v, 30 Seiten
,
Illustrationen
Series Statement:
CRREL Report 88-2
Content:
While many materials undergo phase change at a fixed temperature, soil systems exhibit a definite zone of phase change. The variation of unfrozen water with temperature causes a soil system to freeze of thaw over a finite temperature range. Exact and approximate solutions are given for conduction phase change of plane layers of soil with unfrozen water contents that vary linearly and quadratically with temperature. The temperature and phase change depths were found to vary significantly from those predicted for the constant-temperature or Neumann problem. The thermal conductivity and specific heat of the soil within the mushy zone varied as a function of unfrozen water content. It was found that the effect of specific heat is negligible, while the effect of variable thermal conductivity can be accounted for by a proper choice of thermal properties used in the constant-thermal-property solution.
Note:
CONTENTS
Abstract
Nomenclature
Preface
Introduction
Basic equations
Two-zone problems
Linear unfrozen water function
Quadratic unfrozen water function
Three-zone problems
Linear unfrozen water function
Quadratic unfrozen water function
Conclusions
Literature cited
Appendix A: Derivation of the mushy zone equation
Appendix B: Solution of the two-zone problem with a linear t and variable thermal properties
In:
CRREL Report, 88-2
Language:
English
Keywords:
Forschungsbericht
URL:
https://apps.dtic.mil/docs/citations/ADA195343
URL:
https://hdl.handle.net/11681/9076