| Popis: |
Correlations of flame length L (or height) with the intensity of fires (kW/m2 for area sources or kW/m for line sources) have become foundational to fire behavior science (Byram 1959, Thomas 1963, Nelson and Adkins 1986, among others). Empirical data for these correlations have been based on fires fueled by wood cribs, paper strips, natural gas, and spreading fires at laboratory scales. The data and theory outlined by Thomas (1963, 1967) supported the idea that the horizontal dimension D of an infinite line fire could be neglected if L was much greater than D. Here we report on experiments with line-source fires where the energy release and flame zone dimensions were controlled independently (0.2≤L/D≤13.6), finding that increasing D significantly reduced L over the entire range of observations. Our flame length correlation was more similar to that of Thomas’ (1963) than Byram (1959) but the data clearly showed a strong dependency upon D. This finding suggests that fire behavior studies relying on correlations of L and fireline intensity must consider D to have an important effect on physical processes involved in wildfire behavior. |
