In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar princ...In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar principles.Through the similar experiment and numerical simulation,the distribution of airflow field in the roadway and the spatial and temporal evolution of dust pollution under the conditions of forced ventilation were determined.The airflow field in the roadway can be divided into three zones:jet zone,vortex zone and reflux zone.The dust concentration gradually decreases from the head to the rear of the roadway.Under the forced ventilation conditions,there is a unilateral accumulation of dust,with higher dust concentrations away from the ducts.The position of the equipment has an interception effect on the dust.The maximum error between the test value and the simulation result is 12.9%,which verifies the accuracy of the experimental results.The research results can provide theoretical guidance for the application of dust removal technology in coal mine.展开更多
Forced ventilation is typically used in the construction of tunnels since it is an economical method to provide high amounts of fresh air.Air velocity and pollutant concentration near the work face are determined by t...Forced ventilation is typically used in the construction of tunnels since it is an economical method to provide high amounts of fresh air.Air velocity and pollutant concentration near the work face are determined by the ventilation arrangement.In the study,field measurement of air velocity was performed,and computational fluid dynamics(CFD)models were constructed to investigate airflow near the work face and predict the gas distribution in a gas tunnel construction.The effects of the distance between the air duct exit and the work face(L_(1))were evaluated by analyzing the flow field and pollutant concentration.The evaluation shows that the ventilation efficiency improves if L_(1) does not exceed 15 m in a road tunnel with full-face excavation.With respect to a road tunnel with benching excavation,the effects of bench length(L_(2))are analyzed,and the results of the analysis indicate that ventilation efficiency is optimal when L_(2)=5 m and L_(2)=10 m and the air-duct diameter corresponds to 1.6 m.The CFD results fit the field measurement significantly well,and the current ventilation system in the construction exhibits a relatively high efficiency.The findings of the study aid practitioners in optimizing ventilation efficiency.展开更多
基金National Key R&D Program of China(2022YFC2503200,2022YFC2503201)National Natural Science Foundation of China(52074012,52204191)+5 种基金Anhui Provincial Natural Science Foundation(2308085J19)University Distinguished Youth Foundation of Anhui Province(2022AH020057)Anhui Province University Discipline(Major)Top Talent Academic Support Project(gxbjZD2022017)Funding for academic research activities of reserve candidates for academic and technological leaders in Anhui Province(2022H301)Independent Research fund of Key Laboratory of Industrial Dust Prevention and Control&Occupational Health and Safety,Ministry of Education(Anhui University of Science and Technology)(EK20211004)Graduate Innovation Fund of Anhui University of Science and Technology(2023CX1003).
文摘In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar principles.Through the similar experiment and numerical simulation,the distribution of airflow field in the roadway and the spatial and temporal evolution of dust pollution under the conditions of forced ventilation were determined.The airflow field in the roadway can be divided into three zones:jet zone,vortex zone and reflux zone.The dust concentration gradually decreases from the head to the rear of the roadway.Under the forced ventilation conditions,there is a unilateral accumulation of dust,with higher dust concentrations away from the ducts.The position of the equipment has an interception effect on the dust.The maximum error between the test value and the simulation result is 12.9%,which verifies the accuracy of the experimental results.The research results can provide theoretical guidance for the application of dust removal technology in coal mine.
基金supported by the National Key Research and Development Program(2016YFC0802205),Chinathe National Natural Science Foundation of China(No:64051578460),Chinathe National Key Research and Development Program of China(2016YFC0802200),China.
文摘Forced ventilation is typically used in the construction of tunnels since it is an economical method to provide high amounts of fresh air.Air velocity and pollutant concentration near the work face are determined by the ventilation arrangement.In the study,field measurement of air velocity was performed,and computational fluid dynamics(CFD)models were constructed to investigate airflow near the work face and predict the gas distribution in a gas tunnel construction.The effects of the distance between the air duct exit and the work face(L_(1))were evaluated by analyzing the flow field and pollutant concentration.The evaluation shows that the ventilation efficiency improves if L_(1) does not exceed 15 m in a road tunnel with full-face excavation.With respect to a road tunnel with benching excavation,the effects of bench length(L_(2))are analyzed,and the results of the analysis indicate that ventilation efficiency is optimal when L_(2)=5 m and L_(2)=10 m and the air-duct diameter corresponds to 1.6 m.The CFD results fit the field measurement significantly well,and the current ventilation system in the construction exhibits a relatively high efficiency.The findings of the study aid practitioners in optimizing ventilation efficiency.
