A STUDY OF DEW AND FROST FORMATION ON RETRO-REFLECTORS

THE FORMATION OF DEW AND, AT SUBFREEZING TEMPERATURES, FROST, ON RETRO-REFLECTIVE MATERIALS, WHICH DEPEND ON COLLIMATED INCIDENT LIGHT FOR EFFICIENT REFLECTION, REFRACTS AND SCATTERS THE LIGHT BEAM, RENDERING THEM LESS BRIGHT, MEANS OF RELIEF WERE STUDIED. YEARLY INCIDENCE OF DEW AND FROST WAS DESIRED TOGETHER WITH HOURLY PROGRESS, UNDER CIRCUMSTANCES THAT WOULD PERMIT SIMULTANEOUS DIRECT COMPARISON OF ALL MATERIALS WHENEVER DEW OCCURRED. THE TEST SITE IS LOCATED IN WASHINGTON COUNTY MINNESOTA. THE FINDING AT THIS SITE CAN LIKELY BE COMPARED ONLY TO LOCALITIES HAVING SIMILAR AVERAGE CLIMATOLOGICAL DATA, RELATIVE ELEVATION AND EXPOSURE. TWO GENERAL APPROACHES OF INHIBITING DEW FORMATION ARE /1/ TO CHANGE THE DEW PARTICLE FROM A SPHERICAL DROPLET TO A FILM, AND /2/ REPLACEMENT OF HEAT LOST BY RADIATION. A CHEMICAL SURFACTANT WAS EXPERIMENTALLY. MASSIVE HEAT CONDUCTIVE BACKINGS ILLUSTRATE THAT INTERNAL HEAT STORAGE IS POSSIBLE.

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/hrr/1965/70/70-007.pdf
• Supplemental Notes:
  • 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:
  • WOLTMAN, H L
• Publication Date: 1965

Media Info

• Media Type: Print
• Features: Figures; Tables;
• Pagination: pp 63-66
• Monograph Title: Night Visibility 1963 and 1964
• Serial:
  • Highway Research Record
  • Issue Number: 70
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Alternatives analysis; Conduction; Field tests; Forming; Frost; Heat; Materials; Reflectivity; Reflectorized materials; Retroreflection; Studies; Traffic congestion
• Uncontrolled Terms: Dew; Reflectance
• Geographic Terms: Washington County (Minnesota)
• Old TRIS Terms: Backups; Chemical surfactant; Retrodirective reflection
• Subject Areas: Highways; Materials; Safety and Human Factors;

Filing Info

• Accession Number: 00219549
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Dec 12 1994 12:00AM