Study Of The Complicated Mine Ventilation Network Analysis And Its Adjustment Limits Of The Releveant Parameters

All mankind activities are in a definite circumstance. Atmosphere quality is a very important to employee in mining field, especially in underground mines. One of the aims of mine ventilation system is to provide a suitable environment to meet the sanitarian standard for the work face. Though mine aerodynamics was founded and the theory of mine atmosphere was brought forth many years ago, study of mine ventilation and technology has been conducted continuously and many achievements have made. This progress greatly promotes and enriches the mine ventilation discipline.As concerning with the history of mine ventilation network solution, Scott and Hinsley are the pioneers who use computer to resolve the problem. In recent twenty years in China, many software for mine ventilation network analysis have been developed. However, comparing with the commercial software, the interface and operation methods of software have great different in many ways. The investigation on the effect of mine network parameter changing on the whole network has not been discovered in a literature search. Accordingly, the author selected this area as the topic of investigation in the dissertation. Based on a systematic search of the existing achievements of mine ventilation analysis software in the world, the author developed a new program, and used it for a case of mine ventilation system design. Meanwhile some creative work has been done in the characteristic parameter description and ventilation network improvement. Also, the author has given some corresponding theoretic analysis to the result of the studies using the theory of dissipation structure.In summary, the dissertation included the following synopses.1. Many mine ventilation software invented in the recent years, including their operation platform, user interface, language storage type of data structure and function, were summarized. Based on this review, the contents of the dissertation were put forward.2. Depending on the relevant mine ventilation network analysis theory, a software of mine ventilation network analysis has been developed using Visual C++ language basing on windows, which has some distinct characters, such as visual interface, simple operation and convenience to user.3. An example of complicated mine ventilation was solved by this program. The results meet the aims of optimization of the mine ventilation system.4. Depending upon numerical experiment in computer, the relationship of relevant parameters during mine ventilation network analysis, such as branch number, node number, mesh number, computation accuracy, preliminary value of air flow-rate, iteration number, computation time, convergence and so on, was investigated based on four complicated mine ventilation systems. The results show that a high given computation accuracy greatly influences on the iteration number. Particularly, when the given accuracy reaches 10 m /s to solve a complicated mine ventilation network, the running time is too long to suffer,though a high speed computer is used. Size of the preliminary given value of air flow-rate has little effect on the iteration number and any value except zero can be set. Structure of a network has also some effect on the iteration number. When resistant of a branch in a network is increased to a very big value like setting a sealing in the branch, the whole network analysis results are still in normal and the iteration technique can play the same function.5. By using the theory of dissipative structure and from the relevant parameters of a mine ventilation system, the paper briefly describes the forming process of a mine ventilation system and the system balance. On the base of this approach, a series of results have been drawn out, which may be used to optimize and control the mine ventilation system.