Abstract: A series of experiments on heptane pool fires were conducted in a closed compartment without vents with the inner dimensions of 1 m(L)×1 m(W)×075 m(H), focusing on flame pulsation characteristics. Different pools with the diameters of 0100, 0141, 0200 and 0300 m were investigated. Based on the fact that pulsation frequency of flame bottom area equals that of flame height, a method using flame bottom area was proposed to determine flame pulsation frequency and applied to pool fires in closed compartments with ceiling jet flames. The results show that the variation of flame pulsation frequency is small, and the flame pulsation frequency is smaller than those predicted by empirical equations developed for burnings in free atmosphere while it fits well with the scaling relationship St=026 Fr-0.532, and the expression of f=133D-0.5 is appropriate in describing the relationship between the flame pulsation frequency and pool diameter.

Key words: pool fire, closed compartment, flame pulsation