Study On Gas Explosion Suppression Method Under Flexible Constraint Conditions And Airbag Explosion Suppression System

Gas explosion is one of the frequent disasters in industrial and mining enterprises.The rapid suppression after the explosion is essential to reduce casualties and rescue and disaster relief.Aiming at the problem that the explosion suppression action time of active explosion suppression device is fixed and the flame propagation speed of the actual explosion is not matched,which leads to failure of explosion suppression sometimes.Based on the traditional Chinese philosophy of "using flexible to overcome rigid" and the principle of the automobile airbag,a method of gas explosion suppression under flexible constraints is proposed.Taking methaneexplosion as the research object,a series of experiments were carried out to restrain the gas explosion in the pipe by changing methaneconcentration,quality and type of explosive suppressor,location of explosion suppressor and opening and closing of the pipe network.In order not to influence the current pipe and the normal flow of gas inside the pipe,the explosion suppressor is connected with the pipe through a t-tee pipe.At the moment of explosion in the pipe,the anti-explosion airbag is activated by pre-position explosion characteristic monitoring system.Thus,a flexible barrier containing explosive suppressant in the turbulent state is formed in the pipe,which can directly block the explosion when the explosion shock wave is weak.When the explosion shock wave is strong,the airbag is broken,and the explosion suppressant escapes in the direction of flame propagation,making the explosion suppressant and the flame wave fully contact and mix,so as to achieve the purpose of quickly suppressing the explosion.At present,there is not any report on the explosion suppression technology of airbag at home and abroad.Therefore,explosion suppression technology of airbag proposed in this paper is an original innovation,which opens up a new direction for the research on the suppression of combustible gas explosion.Through a series of experiments,the following innovative results are obtained:(1)A widely used and effective explosion suppression method was found through experiments.The explosion-suppressing structure of airbag based on flexible rigid principle can suppress the explosion of any combustible gas in pipe,and the explosion-suppressing effect is good.This method can effectively solve the mismatch between the flame propagation velocity of methane explosion and the response time of explosion suppression device.It also can achieve consistent explosion suppression effect of methane at any concentration.It has not been reported in domestic andforeign studies.(2)It was proved that recoil effect of explosive suppressant was discovered in the experiment.The PA66 airbag formed a X-type weak plane structure with a thickness of 0.03 mm,and was combined with a certain dose of ultra-fine ABC dry powder.The flame can be completely suppressed when the pre-pressure of the explosion-suppressing airbag is less than 0.436mpa(0.872MPa-1.221 MPa for air tube).The same anti-explosion effect under the same working conditions can reduce the consumption of anti-explosion agent by at least 50%.(3)A complete set of airbag explosion suppression equipment is developed which can be used in the industrial field.The equipment includes explosion characteristic monitoring system and airbag explosion suppression system.The air bag explosion suppression system is mainly composed of gas generator,powder storage tank,ABC dry powder,sealing diaphragm and explosion suppression airbag.The system does not add additional pipe resistance in the pipeline installation.The structure of the whole system is simple and easy to maintain,which is conducive to the miniaturization and economic development of the explosion suppression system.(4)The explosion suppression mechanism of airbag with flexible constraint is analyzed.Based on the characteristics of the elastomer of the airbag,the energy absorption and explosion suppression mechanism of the airbag during the large deformation of the elastomer were analyzed.The mass transfer process between dry powder and flame wave is explained by the theory of different intersection of the same kind of micro wave.Stress intensity factor(sif)in fracture mechanics is used to establish the criterion of airbag failure.The main factors of good explosion suppression effect under the condition of flexible constraint are expounded.The paper contains 121 pictures,19 tables and 156 references.