Wind limit [Maximum reliable wind speed]

n. The theoretical mid-flame wind speed above which increases in wind speed do not increase rate of spread or fireline intensity when using the Rothermel (1972) fire spread model.

 

  • Discussion

 

Wind limit is also called “maximum reliable wind speed” in the BehavePlus fire modeling system . Wind limit is currently used in most fire behavior simulation applications that rely on Rothermel's surface fire rate of spread model, inlcuding BehavePlus, FARSITE, FlamMap, and NEXUS, as well as in nomographs for estimating surface fire rate of spread without use of a computer.

 

  • Units

     

    The wind limit is expressed as a mid-flame wind speed.

     

    Preferred units for wind speed are km/hr in technical reports and papers. Fire Management in the United States still uses the English units mi/hr. Engineering and physics applications may use units of m/s or ft/s. See the following wind speed units conversion table for conversion factors.

     

  • References

    • Rothermel, R.C. 1972. A mathematical model for predicting fire spread in wildland fuels. Res. Pap. INT-115. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station. 42 p.

     

  • See Also

  • Notes

    • Author 

      Joe Scott, Research Forester

      Systems for Environmental Management