Improving methods for calculating air temperature in mine workings equipped with cold water pipelines

摘要

Mining in high temperature conditions may lead to deterioration of miners' health and lower productivit) In recent years, refrigeration equipment has been increasingly used in coal mines in Russia and Ukraine t improve temperature conditions in working places. This is largely because in the last decade new model of mine refrigeration equipment have been designed. The existing methods of calculating cooling loss ii cold water pipelines are imperfect as they suggest calculating mass-transfer coefficient by using empirica dependence, without considering real humidity conditions in mine workings, which results in significan errors. In order to calculate the temperature of cold water in mine air-conditioning systems the heat balanc equation was used, which included the cooling loss to the environment. The mass-exchange processes including the pipeline surface mass-exchange, were calculated by setting the pattern of changes in relativ humidity along the whole length of the mine working. The calculated dependences for the air temperaturi in mine workings that consider the cooling loss from cold water pipelines were corrected, and calculatinj methods were recommended. In order to assess the reliability of calculation of cold water temperature ii mine workings equipped with cold water pipelines, experimental research in the mine was carried out. Thi experimental data were compared to the calculation results. It has been proved that the calculated air anc cold water temperature comply satisfactorily with field observation data and could be recommended fo practical use.