ASABE Technical Library - Abstract

Abstract. Artificial method to construct the fire barrier zone plays an important role in fighting against the prairie fire. The drip type igniter widely used nowadays has some problems such as low efficiency of spraying and slow speed in constructing a prairie fire barrier zone, so develop a new kind of efficient fuel injection ignition machine is very meaningful. This paper introduced a new design of fuel injection ignition machine by the theoretical calculations and experiments. The pneumatic fire extinguisher was transformed into a fuel injection igniter, by improving the air duct of the extinguisher and designing a small centrifugal nozzle. Different air ducts of extinguishers were designed and analyzed by using Fluent to simulate the flow characteristic and the wind speed of the export. The results showed that if the edge of the air duct was designed in a convex arc line and its lines was designed to be tangent to the import and export of the air duct, the export wind speed would be in a range between 23.2 to 25.6 m/s and its direction could be perpendicular to the export edge. Five grid models were constructed according to the different mounting angles（β＝11°, 15°, 19°, 23° and 28°）. From flow curves and pressure curves of the Fluent simulation, it could be concluded that when the export velocity was 23 m/s and the mounting angle of the straight type blades was 11°, the utilization rate of wind energy reached to the highest value. What’s more, the influence of the oil spraying height and the wind speed outside to the uniformity of the boom spray as well as the relation between the fuel injection quantity and the flame of prairie fire barrier zone were studied. Different spraying height had different influences on the spray uniformity under the same wind speed. Even though it is unable to measure the wind speed accurately, it is suggested that 30 cm spray nozzle height should be maintained by using the injector ignition machine to make sure the uniformity of spray. This method could provide a reference for the design of igniter.