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Velocity measurements using hot-wire anemometry - measuring equipment in the mines |
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Velocity measurements using hot-wire anemometry - measuring equipment in the mines Authors: P. Ligęza, E. Poleszczyk
The paper explores the applications of the method of gas flow velocity measurements in mines using the thermal anemometry. The specificity of flow parameters in mines is associated with air contamination, humidity, non-stationary character of flows, variable temperatures. Besides, in outburst-prone mines the safety parameters of the measuring devices are vital (spark protection). For over 40 years the Laboratory of Flow Metrology has been engaged in research work aimed to develop and improve the velocity measurement techniques, with the main emphasis on thermal anemometry. On account of the variety of its application this method might be well employed to solve problems i associated with mine ventilation, airing of mine galleries and improvement of work safety conditions. Measurements of time-variant and transient flows in ventilation networks might be taken with thermal/hot wire anemometers with very wide transmission bands, of the order of several hundred kilohertz. Minute probes enable nearly point-by-point measurements and the velocity and temperature fields are only slightly distorted. The authors provide several solutions of the measuring apparatus specially designed for the mining sector. The paper briefly outlines the newly developed and currently investigated modified method of airflow velocity measurements, well suited to working conditions in the mines and utilising the state-of-the art. measurement techniques.
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2011