Improvement of the mine fire simulation program MFIRE.

摘要

Fire represents one of the most severe hazards to underground mines. A good understanding of the interaction between a mine fire and the mine ventilation network would be very crucial for fire emergency planning and hazard control. MFIRE, an underground mine fire simulation program developed in 1980's, is a tool that can be used to simulate the impacts of a mine fire event to a mine ventilation network. However, the lack of the abilities to simulate some of the important mine fire phenomena realistically hindered its wide applications. This research has been carried out to improve the MFIRE program. The new program, named as MFIRE 2.30, incorporated the following improvements to make is more useful in mine fire simulation: (1) A time-dependent fire model, a t-squared fire, is introduced and incorporated into MFIRE. The t-squared fire model was validated with a fuel fire test conducted in 1990. It has been shown that predicted temperatures of the t-squared fire model agreed well with the measured temperatures. (2) Smoke rollback is a phenomenon in underground mine fire and it could hinder the firefighting efforts and endanger the fire fighters. A semi-empirical model based on a large-scale experiment conducted in a real coal mine entry has been selected to identify the smoke rollback in MFIRE 2.30. The distance of smoke rollback is also estimated and output as an important result of MFIRE 2.30. (3) A moving fire source model to represent a conveyor belt fire has been proposed based on experimental studies on belt fires. The model predicts the flame spread rate along the conveyor belt based on the airflow velocity and the thermal properties of the conveyor belt. Two types of moving fire, a constant spread rate moving fire and non-constant spread rate moving fire were defined. The proposed model has been incorporated into the MFIRE 2.30 program. In addition, a fire can start at any location in a branch, not only at the starting junction of a branch as prescribed in the original MFIRE program.In order to facilitate the continued support and development of the MFIRE program, the program is recoded using an object-oriented programming (OOP) language, Visual C++ (Note: the original MFIRE was coded in FORTRAN 77). A public database interface has been created for the flexible data access. Graphical user interfaces were also provided for easy data input and display of the program outputs.