Safe and energy-efficient ventilation in mines – application of the golden ratio method in designing forced air distribution for ventilation networks

Abstract

Mine ventilation networks are often designed with branches with dependent air currents. Among these, branches connecting the subnetworks of main ventilation fans may be distinguished. Their presence in the ventilation network allows to obtain an infinite number of air distribution variants fulfilling the imposed requirements of distribution. The distributions differ not only in terms of air flow rate in branches, but also in terms of main fan parameters, including their effective power. From the point of view of energy savings, it is beneficial to find such air distribution in which the effective power of the fans exhibits the lowest value.The paper presents an algorithm based on the golden ratio method, allowing to find the optimal air distribution with a certain degree of precision. The presented algorithm is applicable in all ventilation networks with two main fans with interconnected subnetworks.The paper includes an example of a ventilation network in which the method in concern was applied. The effective power of the fans in the network referred to above in the less advantageous scenario amounted to 379.5 kW, while after the optimization, an air distribution variant was found in which the power was limited to 149 kW.