Research on Intelligent Aerial Bomb for Forest Fire Fighting
|School||Harbin Engineering University|
|Course||Mechanical Design and Theory|
|Keywords||cluster bomb TRIZ theory parachute gasbag throwing finite element method|
Forest fire is a kind of severe natural disasters. Crown fire is the most damaging forest fire in all types of forest fires, however, the current firefighting equipment cannot extinguish the fire directly and effectively. This subject derives from the project subsidized by the special fund of Harbin Engineering University "Research on intelligent aerial bomb for forest fire fighting" (PN:HEUCFZ1025) which is collaborate with CSSC Jiujiang Changan Fire Fighting Equipment CO. Ltd. The purpose of this paper is to design an intelligent aerial bomb to extinguish the crown fire which is the most difficult to fight against. The aerial bomb is a kind of cluster bomb which is carried by helicopter and airdropped over the fire ground. The series of action of cabin opening of the dispenser, ejection of the submunition, auto-throw parachute and decelerating can be completed accurately under the control of intelligent control system, which ensures the bomb explodes and disperses extinguishing agent at the height just in the crown fire, thus, the optimal fire-fighting effect can be fulfilled.The classification of the forest fire and the present development situation at home and abroad of the forest fire fighting were introduced in this paper, subsystems and conceptual model of the aerial bomb were obtained by analyzing and solving the contradiction of fire fighting process with TRIZ theory, and then the overall structure of the aerial bomb is obtained with the considering of actual situation.External ballistics model of the submunition was established to meet overall technical requirements by considering the specific conditions of flying. Parameters and curve of external ballistics was obtained via simulation with software MATLAB. The particular parameter of the parachute was obtained via calculating the external ballistics parameters. Connector between the submunition, the parachute and the projecting parachute equipment were researched according to the demand and procedure of projecting parachute.The gasbag throwing was selected as separation mode of submunition via analyzing characteristics of all kinds of separation mode. Dynamic mode of the process of submunition projecting parachute and parameters of gasbag were established by combining with external ballistic parameters. The specific design procedures of parts of separation system were described. Finally, the simulating of impacts on the system in the process of separation and parachute opening was carried out. To verify the reliability of the system, numerical simulation was carried out by means of of procedures via finite element method and software ANSYS. The result shows that intensity of system can meet all processes reliably.