Forecasting Temperature Change in Mine Workings at Change in Air Flow

Abstract

AbstractThe aim of this article is to assess the impact of change in base air flow, the assumed amount of air flow set during design phase of a structure, on the accuracy of air temperature forecasting at specific locations in a network of underground mine workings in the cryolithic zone. A simple analytical relationship to determine the correction coefficient was obtained as a result of data analysis. It allows to assess the degree to which change in base air flow affects air temperature change. A comparison of accuracy and reliability of the proposed approach towards assessing the air temperature changes in mine workings when airflow within them changes was conducted. In particular, it was shown that this approach allows to obtain sufficiently reliable data to assess the air temperature change in a specific location in the mine working network without requiring a demanding analysis of the status of the entire network. The value of error in the data does not exceed 10%, a boundary of error usually permitted in engineering calculations. It was determined that the correction coefficient largely changes depending on the relative increase in air flow, rather than absolute increase. At that, the larger the area of mine working’s section, the lower is the permissible increase in base airflow, regardless of initial air flow volume. The lower the base temperature in the terminal point, the stronger is the impact of increase in base air flow on air temperature. The results of variant calculations are presented in the form of 2D and 3D charts. The use of charts allows to quickly assess the values of the correction coefficient for a wide range of ventilation conditions of the underground mine workings in the cryolithic zone.KeywordsCryolithic zoneMine workingAir flowTemperatureForecastingVentilationCalculation error