Finite Element Model of Transient Heat Conduction with Isothermal Phase Change (Two and Three Dimensional).

• Main Authors: Guymon,G L, Hromadka,T V , II
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER N H
• Format: Text
• Language: English
• Published: 1977
• Subjects: Soil Mechanics; Snow; Ice and Permafrost; Computer Programming and Software; Thermodynamics; *COMPUTERIZED SIMULATION; *COLD REGIONS; *SOIL MECHANICS; *THERMAL CONDUCTIVITY; COMPUTER PROGRAMS; PROGRAMMING MANUALS; MATHEMATICAL MODELS; TRANSIENTS; DEGRADATION; TWO DIMENSIONAL; FINITE ELEMENT ANALYSIS; THREE DIMENSIONAL; FORTRAN; PARTIAL DIFFERENTIAL EQUATIONS; FROST; ROADS; THAWING; HEAT FLUX; PERMAFROST; DAMS; PE62719A; AST42; WU006; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA047369; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA047369

The partial differential equation for transient heat conduction is solved by a finite element analog using a quadratic weighting function for the discretized spatial domain. The transient problem is solved by the Crank-Nicolson approximation. Two-dimensional and three-dimensional models incorporated in the same computer program are presented. The finite element method is reviewed, assumptions and limitations upon which the model is based are presented, and a complete derivation of the system analog is included. Certain problems can only be modeled as a three-dimensional system, e.g. thaw degradation around roadway culverts, embankment dams on permafrost where dam length is short relative to dam width, and thaw and freezeback under buildings. In most cases, however, the more economical two-dimensional model can be used. Numerical tests of both models have been accomplished but field verification has not been attempted. A user's manual and a FORTRAN IV computer listing of the program are presented. (Author)