TWO-DIMENSIONAL FINITE DIFFERENCE TECHNIQUES APPLIED TO TRANSIENT TEMPERATURE CALCULATIONS IN HOT-MIX ASPHALT CONCRETE WINDROWS

THE APPLICATION OF FINITE-DIFFERENCE TECHNIQUES TO A PROBLEM IRRESOLVABLE BY ANALYTICAL METHODS, REVEALED SIGNIFICANT QUANTITATIVE INFORMATION ABOUT COOLING RATES OF HOT-MIX ASPHALT CONCRETE WINDROWS UNDER VARIED ENVIRONMENTAL CONDITIONS. THIS STUDY CALCULATES THE CHANGES WITH TIME IN AVERAGE BULK TEMPERATURE OF SUCH WINDROWS OF DIFFERENT SIZES AND INITIAL TEMPERATURES UNDER THE FOLLOWING ENVIRONMENTAL CONDITIONS: THE BASE MATERIAL TEMPERATURE, THE AMBIENT TEMPERATURES, THE NET ABSORBED SOLAR RADIATION, AND THE WIND VELOCITY. THE ANALYTICAL SOLUTION OF THE MATHEMATICAL MODEL DESCRIBING THE WINDROW AND ITS IMMEDIATE SURROUNDINGS CANNOT BE OBTAINED. THEREFORE, THE APPROACH USED WAS A 2-DIMENSIONAL TRANSIENT HEAT BALANCE MODEL FORMULATED BY EXPLICIT FINITE-DIFFERENCE TECHNIQUES IN FORTRAN-IV. THE RESULTS OF THE FINITE-DIFFERENCE SOLUTION WERE THOSE READILY PREDICTED BY THE LAWS OF HEAT TRANSFER. THE MOST SIGNIFICANT VARIABLE AFFECTING THE COOLING RATES WAS THE SIZE OF THE WINDROW. THE LARGE WINDROWS, HAVE A LOWER SURFACE-TO-VOLUME RATIO THAN SMALLER WINDROWS, WERE LESS AFFECTED BY ALL ENVIRONMENTAL CONDITIONS (THE MOST SEVERE CASE USED WAS 10 F BASE TEMPERATURE, 10 F AMBIENT TEMPERATURE, OVERCAST DAY, AND STILL WIND), THE TEMPERATURE DROP AFTER 30 MINUTES WAS 67 F FOR A 2- BY 1-FT WINDROW BUT ONLY 24 F FOR A 6- BY 3-FT WINDROW. THE COMPUTER PROGRAMS DEVELOPED IN THE STUDY MAY BE USED TO CALCULATE BULK TEMPERATURE VERSUS TIME CURVES FOR AN ALMOST LIMITLESS NUMBER OF COMBINATIONS OF WINDROW SIZES, INITIAL TEMPERATURES, ENVIRONMENTAL CONDITIONS, AND COOLING TIMES.

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/hrr/1973/454/454-004.pdf
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0309021871
• Supplemental Notes:
  • Publication of this paper sponsored by Committee on Flexible Pavement Construction. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Authors:
  • Fishback, J W
  • Dickson, P F
• Conference:
  • 52nd Annual Meeting of the Highway Research Board
  • Location: Washington District of Columbia, United States
  • Date: 1973-1-22 to 1973-1-26
• Publication Date: 1973

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: pp 32-38
• Monograph Title: Construction
• Serial:
  • Highway Research Record
  • Issue Number: 454
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Asphalt concrete; Computer programs; Deposits (Geology); Finite differences; Hot mix asphalt; Mathematical models; Solar energy; Temperature; Velocity; Wind
• Identifier Terms: FORTRAN (Computer program language)
• Old TRIS Terms: Wind velocity; Windrows
• Subject Areas: Construction; Geotechnology; Highways;

Filing Info

• Accession Number: 00215688
• Record Type: Publication
• ISBN: 0309021871
• Files: TRIS, TRB
• Created Date: Jun 5 1974 12:00AM