Determining the depression of the natural airflow using a calculation method.

Abstract

Natural draft, as is known, is the result of the difference in the weight of the air in the intake and return airways. In accordance with this, the depression of natural draft depends on weight, i.e., on the temperature and air pressure in the outgoing and incoming air currents. Moreover, depending on the depression developed by the exhaust or forcing fan, the air density of the return or intake current can vary within significant limits, so that, along with the natural draft formed as a result of the heating of the air and changes in its composition, there is also a draft created by the fan – an “artificially created natural draft”. Currently, in addition to calculation methods, a number of methods are known for directly measuring the depression of the natural draft of an existing mine. These methods are associated with changing the ventilation regime of the mine. By blocking the entire air current with a stopping (or bulkhead), one can directly measure the natural draft depression with a micromanometer, connecting it to both sides of the stopping.

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