Numerical study on dust movement and dust distribution for hybrid ventilation system in a laneway of coal mine

Suppressing and removing mine dust from the working face is an important task for underground mines worldwide. In this paper, a numerical study was carried out to investigate the influence of ventilation arrangement on the mechanism of dust distribution. The Woxi Pithead of Hunan Chenzhou Mining Co., Ltd, China, was used as a case study, which adopted a widely used far-pressing-near-absorption (FPNA) ventilation system. Based on the theory of gas-solid two-phase flow, the program ANSYS Fluent was utilized, and the three-dimensional airflow migration and dust diffusion numerical models were simulated. The established computational fluid dynamics (CFD) models were validated using the airflow velocity data and the dust concentration data monitored at different positions from the operating coal mine. A comprehensive sensitivity study was conducted to investigate the influence of four parameters on dust suppression, including the distance of pressure air duct outlet from working face (Lp-outlet), the distance of exhaust air duct inlet from working face (Le-inlet), the ratio of pressing air volume to lab sorption air volume (K), and the installation height of the air duct (H). The optimum ventilation layout parameters were obtained through the simulation of the wind field and dust behaviour. The results show that there were four regions during the airflow field, namely, the jet zone, the recirculation zone, the vortex zone, and the mixing zone of pressure and exhaust airflow. All four parameters were found to have an important influence on the mass concentration of dust, and the optimum ventilation layout parameters were determined to be Lp-outlet = 18 m, Le-inlet = 3 m, K = 1.2, and H = 1.6 m.

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Numerical study and field performance of rockbolt support schemes in TBM-excavated coal mine roadways: A case study

Tunnelling and Underground Space Technology ◽

10.1016/j.tust.2021.104053 ◽

2021 ◽

Vol 115 ◽

pp. 104053

Author(s):

Bin Tang ◽

Mathias Yeboah ◽

Hua Cheng ◽

Yongzhi Tang ◽

Zhishu Yao ◽

...

Keyword(s):

Coal Mine ◽

Numerical Study ◽

Field Performance ◽

Mine Roadways ◽

Rockbolt Support

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Economic feasibility of fan-assisted hybrid ventilation system in apartment housings in Korea

Advances in Civil, Architectural, Structural and Constructional Engineering ◽

10.1201/b19961-32 ◽

2016 ◽

pp. 139-142

Author(s):

Y Kim ◽

J Lee ◽

G Choi

Keyword(s):

Ventilation System ◽

Economic Feasibility ◽

Hybrid Ventilation

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The Optimum Arrangement of Working Face Ventilation System for Coal Mine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.1691 ◽

2012 ◽

Vol 482-484 ◽

pp. 1691-1694

Author(s):

Ning He ◽

Qiu Ju Ma ◽

Yu Zhu Shi

Keyword(s):

Coal Mine ◽

Ventilation System ◽

Dynamics Simulation ◽

Practical Significance ◽

Gas Migration ◽

Optimal Layout ◽

High Concentration ◽

Working Surface ◽

Working Face ◽

Optimum Arrangement

It was most effective and practical that using computational fluid dynamics simulation to analyze the distribution of flow field in gob for studying optimal layout scheme of the working face ventilation system. In this paper, numerical simulation was applied for studying the migration laws and high concentration of gas gathering area of N1201 working face in Tunliu Coal Mine; the gob of robbing working surface gas migration laws and high concentration of gas gathering area was obtained; the optimum arrangement of ventilation system for the working face was given. The conclusions had a certain theoretical value and practical significance for controlling the working face gas.

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The Ventilation Performance Analysis of a Fan-assisted Hybrid Ventilation System

Journal of The Korean Society of Living Environmental System ◽

10.21086/ksles.2015.06.22.3.454 ◽

2015 ◽

Vol 22 (3) ◽

pp. 454

Author(s):

Jong-Eun Lee ◽

Jae-Sik Kang ◽

Yu-Min Kim

Keyword(s):

Performance Analysis ◽

Ventilation System ◽

Hybrid Ventilation ◽

Ventilation Performance

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Numerical study of the air distribution in the Crew Quarters on board of the International Space Station

E3S Web of Conferences ◽

10.1051/e3sconf/20198502015 ◽

2019 ◽

Vol 85 ◽

pp. 02015 ◽

Cited By ~ 1

Author(s):

Charles Berville ◽

Matei-Răzvan Georgescu ◽

Ilinca Năstase

Keyword(s):

Numerical Simulations ◽

International Space Station ◽

Numerical Study ◽

Ventilation System ◽

Space Station ◽

Air Distribution ◽

Thermal Manikin ◽

Airflow Rate ◽

International Space ◽

Airflow Distribution

The current concept of Crew Quarters on board of the International Space Station has several issues according to the crew member’s feedback. Major issues concern noise levels, the accumulation of CO2 and the quality of the air distribution. Our study targets the airflow distribution, to diagnose this issue, we realise a series of numerical simulations (CFD) based on a real scale replica of the Crew Quarters. Simulations were set with a zero-gravity mode and with the theoretical air parameters inside the SSI. The geometry includes a thermal manikin having the neutral posture of a body in the absence of gravity. Numerical simulations were run for the three different air flow rates provided by the current ventilation system. Results have shown that the air distribution inside the Crew Quarter is insufficient for low airflow rates but becomes acceptable for the higher airflow rate, however the higher airflow rate can potentially produce draught discomfort.

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Numerical Assessment of Fan-Ducting Coupling for Gas Turbine Ventilation Systems

Volume 1: Aircraft Engine; Fans and Blowers; Marine ◽

10.1115/gt2015-42449 ◽

2015 ◽

Cited By ~ 1

Author(s):

Alessandro Corsini ◽

Giovanni Delibra ◽

Stefano Minotti ◽

Stefano Rossin

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Static Pressure ◽

Numerical Study ◽

Characteristic Curve ◽

Ventilation System ◽

Maximum Pressure ◽

Term Operation ◽

Axial Fans ◽

Pressure Discontinuity

Gas turbines enclosures entail a high number of auxiliary systems which must be preserved from heat, ensuring therefore the long term operation of the internal instrumentation and of the data acquisition system. A dedicated ventilation system is designed to keep the enclosure environment sufficiently cool and dilute any gas coming from potential internal leakage to limiting explosion risks. These systems are equipped with axial fans, usually fed with air coming from the filter house which provides air to the gas turbine combustion system, through dedicated filters. The axial fans are embedded in a ducting system which discharges fresh air inside the enclosure where the gas turbine is housed. As the operations of the gas turbine need to be guaranteed in the event of fan failure, a backup redundant system is located in a duct parallel to the main one. One of the main requirements of a ventilation fan is the reliability over the years as the gas turbine can be installed in remote areas or unmanned offshore platforms with limited accessibility for unplanned maintenance. For such reasons, the robustness of the ventilation system and a proper understanding of coupling phenomena with the axial fan is a key aspect to be addressed when designing a gas-turbine system. Here a numerical study of a ventilation system carried out with RANS and LES based methodologies will be presented where the presence of the fan is synthetized by means of static pressure discontinuity. Different operations of the fans are investigated by means of RANS in order to compare the different operating points, corresponding to 1) clean and 2) dirty filters operations, 3) minimum and 4) maximum pressure at the discharge section. Large Eddy Simulations of the same duct were carried out in the maximum loading condition for the fan to investigate the unsteady response of the system and validate its correct arrangement. All the simulations were carried out using OpenFOAM, a finite volume open source code for CFD analysis, treating the filters as a porous medium and the fan as a static pressure discontinuity according to the manufacturer’s characteristic curve. RANS modelling was based on the cubic k-ε model of Lien et al. while sub-grid scale modelling in LES was based on the 1 equation model of Davidson. Computations highlighted that the ventilation system was able to work in similarity for flow rates between 15 m3/s and 23.2 m3/s and that the flow conditions onto the fan suggest that the aerodynamic stress on the device could be reduced introducing in the duct flow straighteners or inlet guided vanes.

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