Effects of forced-air volume and suction region on the migration and dust suppression of air curtain during fully mechanized tunneling process

Actuality of Research. Scientific works proved that the greater the volume of the lungs, the better the physical abilities of athletes. So researching of the functional state of organism, namely the level of lung capacity of volleyball players is very important. The aim of the Researching. Determining of the level of lung capacity, forced air volume in 1 second and peak expiratory flow rate in volleyball qualifications. Results. The average rate of lung capacity of volleyball players is – 3,98 l, Forced air volume in 1 second – 3,32 liters, peak expiratory flow rate 5,77 – l/sec. Conclusions. The results of researching indicate that the level of vital capacity in girls is rather higher. So volleyball players (girls) have a high level of fitness of the body, providing adaptation to hight loads and hight endurance.

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CFD-Based Determination of the Optimal Blowing and Suction Air Volume Ratio of Dual-Radial Swirl Shielding Ventilation in a Fully Mechanized Excavation Face

Geofluids ◽

10.1155/2021/5473256 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Kuan Wu ◽

Shiliang Shi ◽

Yijie Shi ◽

Yong Chen

Keyword(s):

Ventilation System ◽

Volume Ratio ◽

Simulation Method ◽

Dust Concentration ◽

Dust Control ◽

Underground Mines ◽

Physical And Mental Health ◽

Control Effect ◽

Air Curtain ◽

Air Volume

Dust is one of the main pollutants in coal mines, which seriously affects the physical and mental health of workers, as well as the safe production in underground mines. Dual-radial swirl shielding ventilation is a new ventilation method for a fully mechanized excavation face and can effectively reduce the dust concentration in the underground. The dust control effect of dual-radial swirl shielding ventilation is mainly affected by the thickness and integrity of the shielding air curtain, as well as the disturbance of the flow field near the air curtain. By changing the blowing and suction air volume ratio of the air duct, the strength of the radial air curtain can be improved, and the dust control effect of the dual-radial swirl shielding ventilation system can be effectively improved. In order to determine the optimal operating parameters of the dual-radial swirl shielding ventilation system, a numerical simulation method was used to conduct an in-depth study on the blowing and suction air volume ratio of the system. The results showed that when the blowing and suction air volume ratio of the air duct was 1.5, the radial air curtain had the highest strength. Under this condition, the dust concentration at the driver’s position of the roadheader was the lowest, and the dual-radial swirl shielding ventilation system can achieve an ideal dust control effect.

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The Rijnlandroute bored tunnel – Continuously improving the mechanized tunneling process

Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art ◽

10.4324/9781003031635-18 ◽

2020 ◽

pp. 2723-2733

Author(s):

H. Mortier ◽

M. Brugman ◽

B. Peerdeman ◽

T. Schubert

Keyword(s):

Tunneling Process ◽

Mechanized Tunneling

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The Rijnlandroute bored tunnel – Continuously improving the mechanized tunneling process

Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art ◽

10.1201/9780429424441-288 ◽

2019 ◽

pp. 2723-2733

Author(s):

H. Mortier ◽

M. Brugman ◽

B. Peerdeman ◽

T. Schubert

Keyword(s):

Tunneling Process ◽

Mechanized Tunneling

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Influence of the strip-shaped air-out slits’ width in the fully mechanized working face under wallattached swirling ventilation condition

E3S Web of Conferences ◽

10.1051/e3sconf/20198101016 ◽

2019 ◽

Vol 81 ◽

pp. 01016 ◽

Cited By ~ 1

Author(s):

Yongjun Li ◽

Pengfei Wang ◽

Ronghua Liu ◽

Han Han ◽

Xuanhao Tan ◽

...

Keyword(s):

Control Effect ◽

Control Block ◽

Air Curtain ◽

Ventilation Condition ◽

Air Volume ◽

Working Face ◽

Airflow Field ◽

Fluent Software ◽

Dust Diffusion ◽

Bag Precipitator

For the purpose of mastering the influence of the strip-shaped air-out slits’ width in the fully mechanized working face under wallattached swirling ventilation condition, By using fluent software, numerical simulation of airflow field and dust diffusion in fully mechanized working face under different strip-shaped air-out slits’ width conditions was carried out. The results show that the wall-attached swirling ventilation can effectively control the dust diffusion in the fully mechanized working face, improve the dust collecting effect of the bag precipitator fan, and reduce the particle mass concentration at the driver and the rear of the tunnel; Increasing the air volume of the strip-shaped airout slits can improve the control effect of the swirling air curtain on the dust, appropriate air volume can make the swirling air curtain control the dusty airflow and push it to the end of the heading surface to control, block and propel the dust; When the width of the strip-shaped air-out slits is 0.06 m, the dust collecting effect of the exhaust air cylinder on the dust and the effect of the wall-attached swirling on the plugging of the dust are best.

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Influence of forced air volume on water evaporation during sewage sludge bio-drying

Water Research ◽

10.1016/j.watres.2013.03.048 ◽

2013 ◽

Vol 47 (13) ◽

pp. 4767-4773 ◽

Cited By ~ 42

Author(s):

Lu Cai ◽

Tong-Bin Chen ◽

Ding Gao ◽

Guo-Di Zheng ◽

Hong-Tao Liu ◽

...

Keyword(s):

Sewage Sludge ◽

Water Evaporation ◽

Air Volume ◽

Forced Air

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Study on the influence of air curtain barrier efficiency on infiltration air volume and temperature distribution in large space in winter

Procedia Engineering ◽

10.1016/j.proeng.2017.09.982 ◽

2017 ◽

Vol 205 ◽

pp. 2509-2516 ◽

Cited By ~ 1

Author(s):

Hong Ye ◽

Jinghua Yu ◽

Biaobiao Wang ◽

Yunxi Liu ◽

Hui Guo ◽

...

Keyword(s):

Temperature Distribution ◽

Large Space ◽

Air Curtain ◽

Air Volume ◽

Barrier Efficiency

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Determination of optimal blowing-to-suction flow ratio in mechanized excavation face with wall-mounted swirling ventilation using numerical simulations

International Journal of Coal Science & Technology ◽

10.1007/s40789-020-00384-3 ◽

2021 ◽

Author(s):

Runze Gao ◽

Pengfei Wang ◽

Yongjun Li ◽

Ronghua Liu

Keyword(s):

Ventilation System ◽

Simulation Models ◽

Distribution Patterns ◽

Flow Ratio ◽

Discrete Phase Model ◽

Dust Suppression ◽

Air Curtain ◽

Suppression Effect ◽

Airflow Field ◽

Suction Flow

AbstractWall-mounted swirling ventilation is a new type of system in mechanized excavation faces with a dust suppression performance that is closely related to the blowing-to-suction flow ratio. Physical and simulation models were developed according to the No. C103 mechanized excavation face in the Nahe Coal Mine of the Baise Mining Bureau, Guangxi Province to optimize the blowing-to-suction flow ratio for wall-mounted swirling ventilation. Both the k-ε turbulence model and the discrete phase model were utilized to simulate airflow field structures and dust concentration distribution patterns at various blowing-to-suction flow ratios. The results suggest that higher blowing-to-suction flow ratios increase the airflow field disturbance around the working face and weaken the intensity of the axial air curtain. On the other hand, both the intensity of the radial air curtain and the dust suppression effect are enhanced. At a blowing-to-suction flow ratio of 0.8, the wall-mounted swirling ventilation system achieved the most favorable dust suppression performance. Both the total dust and respirable dust had their lowest concentrations with maximum efficiencies of reducing both types at 90.33% and 87.16%, respectively.

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