Aerodynamic potentials and a designation of their fields in ventilation networks, sub-networks and r

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Aerodynamic potentials and a designation of their fields in ventilation networks, sub-networks and regions Author: H. Bystroń The verification shows, that the aerodynamic potential (1.1) is precise. However, the potentials (1.2), (1.8), (1.10) and (1.12) are approximate. The cause is, in the case of the potential (1.2), the assumption of a non-moving atmosphere layered isentropically instead of a reversible isentropic flow; in the case of the potentials (1.8), (1.10) and (1.12) the cause is the assumption of the formulas (1.7), (1.9), (1.11) instead of a Poisson's equation in the form (2.1), respectively. Reasoning along a new way that takes advantage of a movement equation, a reversible insentropic equation (2.1), an energy equation (3.5) for the isentropic reversible flow and an equation of natural ventilation pressure (4.1), we reach the exact aerodynamic potentials (4.9), (5.5). In these potentials a pressure (4.10) and a density (5.1) in isentropic reversible flow are present, respectively. Accordingly with the field theory, we prove that the potentials (4.9), (5.5) are precise scalar potentials. The definitions of the notions appearing in the work, namely: a non-frontier region, a frontier region, a ventilation network and a sub-network are included. In a non-frontier region the fields of the potentials (6.9), (6.10) are designated, with the reference level (6.8), verified by the control pressure (6.11). In a sub-network, as well as in a network containing frontier regions the fields of the potentials (4.9), (5.5) are designated with the reference level (2.1), verified by the control pressure (4.10). According to the assumed definition, a ventilation network comprises at least two intake shafts. Typically, the parameters of air in the "0" cross-sections of the intake shafts are not the same, therefore the reference levels of the fields of potentials (4.9), (5.5) are different. So, the reference levels have to be balanced. For example, in the sub-networks and non-frontier regions in "Niwka-Modrzejów" and "Staszic" coal mines we designate respectively: the fields of potentials (4.9), (5.5) and (6.9), (6.10) as well as their reference levels (2.1) and (6.8) verified by the control pressures (4.10) and (6.11). In the network with two sub-networks containing two frontier regions in "Halemba"' and "Śląsk" coal mines and in the network comprising three sub-networks containing three frontier regions in "Halemba", "Śląsk" and "Polska-Wirek" coal mines we designate the fields of the potentials (4.9), 0(5.5) and their reference levels (2.1) verified by control pressures (4A0). Then the reference levels are balanced. A suggestion was put forward that in order to ameliorate the state of occupational safety and ventilation economy in mines, the ventilation methods basing on the following ought to be implemented: - fields of the exact potential (1.1) in planned ventilation networks, sub-networks and regions, - fields of the exact potential (4.9) lub 0(5.5) in operating ventilation networks, sub-networks and regions. Some supplementary questions relating to this work are taken up.

 

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