Coal And Gas Outburst Shock Wave Experimental Study

Starting from the characteristics of frequent and complexity about accidents of china's coal and gas outburst, this paper researches coal and gas outburst and the resulting shock wave from the theoretical analysis and experimental research, and has a systematic simulation study on the coal and gas pipeline after the experimental shock wave propagation within a prominent. Meanwhile, on the roadway within the coal and gas outburst shock wave propagation characteristics are studied and summarized.This paper contains four parts: theoretical analysis, establishing experimental system under the guidance of theory , experimental test structures, comparison and summary of experimental results and theoretical analysis. Firstly, under the guidance of the similarity theory a test system is designed on coal and gas outburst. The system consists of two parts of outbursting achievement system and data acquisition system. The prominent coal and gas is completed through an analog system of implementation experiment,and then signals which do Pressure Transmitter collect through the dynamic data acquisition system were transmitted into digital signals,in order to test the characteristics pressure changes which shock wave generated; Secondly, according to aerodynamic theory,the article analysises outbursting occurrence and development to the impacting factor of the shock wave propagation(the amount of coal highlighting, the amount of gas t and gas pressure, the layout of test pipe and the level of roughness, etc.);by intermittent relationship based on shock wave ,gas equation of state is established,thus overpressure shock wave transmission formula and the expression rate of shock wave front is derived. In Experimental research section, the theoretical analysis of coal and gas outburst on the conclusions of shock wave transmission is verified in experiment. Through simulation experiments, in which give different amount of coal, different gas pressure, different gases and different gas in case of prominent roadway layout, the results analysis the impacting relationship between highlighting shock wave in these types of cases.The results show that the entire experimental system of independent design could simulated this complex dynamic phenomena of coal and gas outburst,and simulated the developing process of a prominent place in the roadway successfully. Futher, there are many impacting factors of producing shock wave size,which of the most important is the expansion energy of coal gas stored in the body(the strength degree of coal and gas outburst),and the initial overpressure generated by Coal and gas outburst is closely related to gas pressure which can also be verified by overpressure shock wave equation and Shock wave airflow propagation velocity formulas. This research has provided an important theoretical and technical support for coal and gas outburst accident prevention and investigation and prevention of the disaster expansion after the occurrence of coal and gas outburst.