presented in this paper relate to fire ignition, fire growth, flashover and post-flashover fully developed fires。
Fire ignition criteria
To minimize ignition, the radiant heat flux required to ignite a material is usually used as the criterion with thresholds established for various materials。 Table 1 illustrates the lower and upper values proposed for both radiant heat flux and surface temperature for ignition of some materials on use in ships。
Table 1: lower and upper limit of some deterministic criteria
1)
in the slow growth is takes the value of 1000 BTU/s (1055 kW equivalent) for 600 seconds;
2)in the medium growth is takes the value of 1000 BTU/s (1055 kW equivalent) for 300 seconds;
3)in the fast growth is takes the value of 1000 BTU/s (1055 kW equivalent) for 150 seconds;
4)in the ultra fastt growth is takes the value of 1000 BTU/s (1055 kW equivalent) for 75 seconds;
In other words these types of fires are characterized by the same maximum value, which is 1 Mw (1055 kW) and is realized in different times。
The decrement phase has the same time than that of the increment。
Type/Stage Deterministic Criteria Lower Limit Upper Limit
Ignition Radiant Heat Flux for Ignition (kW/m^2) Pilot Spontaneous Pilot Spontaneous
12 - 27 28
Surface Temperature (°C) 270 - 350 600
Flashover Time to reach flashover - - Temperature (°C) Radiation (kW/m^2)
600 20
Fire growth Glass breakage temperature (°C) Ordinary Glass Tempered Glass Ordinary Glass Tempered Glass
100 270 175 350
Life safety Convection heat (°C) 65 190
Radiation Heat (°kw/m^2) 2。5 2。5
Oxygen (%) 10 15
Carbon monoxide (ppm) 1400 1700
Carbon dioxide (%) 5 6
Visibility (m) fire compartment other rooms fire compartment other rooms
2 - 3 -
Depending on the fuel in-place, the fire may have a growth rate that is either slow, medium, fast, or ultra fast。 The fire will continue to grow with time until its heat release rate reaches a maximum level, which is governed by both the area of the fuel and the ventilation conditions。 For design purposes, the maximum heat release rate per unit fuel area may be obtained from available experimental data。 船舶设计中的消防安全性能分析英文文献和中文翻译(4):http://www.youerw.com/fanyi/lunwen_94979.html