The progress of micro electric devices at the present day has made it possible to plan mine ventilation real time control which is one of the effective methods for safety in mine. The development of not only hardwear but also softwear will be required for real time control of mine ventilation. In this paper, some factors about a softwear for this purpose are explained.
Main results are as follows;
1) A new method of solving airflow rates in a network by combinating quadratic equation method and ‘The Hardy Cross method’ converges more rapidly than a method by using ‘The Hardy Cross method’ only.
2) Making a depression diagram and a depression loss-airflow rate (H-Q) diagram from mine ventilation analysis, the condition of ventilation in a network is shown graphically.
3) When natural ventilation pressure “HN” acts at a closed circuit “C” in a network, energy “FQ” supplied by a fan depends on aerodynamic resistances of branch in “C”. To make energy “FQ” less, it is profitable that airflow in a branch having small aerodynamic resistance is the same direction as “HN” and airflow in a branch having large one is the contrary.
4) Aerodynamic resistance of branch in a network can be determined, approximately, by simulation method from working points of fans and airflow rate measurement at all the branches under different condition of the network.
