Assessement of uncertainity analysis of mine fans by studing ventilation network design

Abstract

The objective of a ventilation network system is to provide the desire quantity of airflows throughout the mine such that the workers can work underground in a safe and healthy environment at the level specified by the mining regulations. In coal mines the ventilation network system has a greater impact on safety and production. The selections of mine fan and air quantity calculation at different working places are generally decided by solving the ventilation network using iterative Hardy-Cross method. In this thesis, an approach was adopted to simulating the ventilation network considering the airways resistances as uncertain variables. A Monte-Carlo simulation-based approach was followed to generate random set of resistance values from the distribution functions of the airways resistances. The VENTSIM software was used to solve the Hardy-Cross method for ventilation network simulation using one set of random resistance values. The Monte-Carlo simulation based approach helps to analysis the uncertainty of air quantity at specific working faces as well as total quantity required for ventilating the mine. The major focus of the thesis is towards the quantity of air in the working face generated by the mine main fan and the risk involve with the selection of mine main fan for a coal mine. The methodology for the ventilation network design proposed in this thesis was applied in a underground coalmine in Eastern part of India. The airways resistances are calculated by measuring the values at different places in same airways. The mean and standard deviation used for Monte-Carlo simulation assuming the distribution is Gaussian. A total number of 71 airways are simulated in the case study mine. A risk analysis of quantity of air reaching at face was performed at 3 working faces by generating 200 realizations.The results in this thesis was validated my measuring quantity at different measuring station in this mine.