Dust diffusion simulation in the third layer construction of underground powerhouse

Abstract

Under forced ventilation, the dust diffusion of underground powerhouse construction is investigated using a 3D high Reynolds number k-ɛ model. The interfacial momentum transfers and the wall roughness in the wall function are considered. Ventilation in the third layer of underground powerhouse of Xiangjiaba hydropower station is used as a case. The geometric structure has a decisive effect on the airflow distribution. It is concluded that the dust concentration decreases gradually with the increase of the ventilation time. However, iso-concentration curves have the same tendency after 1 800 s. The dust concentration meets the ventilation and dust-prevention health standard after 2 300 s. The prediction by the present model is confirmed by the experimental measurement by Nakayama.

Keywords

dust concentration / construction ventilation / numerical simulation / underground powerhouse / third layer

References

[1] Ministry of China National Water ResourcesHydropower Engineering Corporation. Handbook of Construction Planning of Hydraulic and Hydroelectric Projects (Vol. II): Construction Technique[M]. 1997, Beijing: China Water Conservancy and Hydropower Press.

[2] Laslandes S., Sacé C. Transport of particles by a turbulent flow around an obstacle: A numerical and a wind tunnel approach[J]. Journal of Wind Engineering and Industrial Aerodynamics, 1998, 74(6): 577-587.

[3] Klemens R., Kosinski P., Wolanski P., et al. Numerical study of dust lifting in a channel with vertical obstacles[J]. Journal of Loss Prevention in the Process Industries, 2001, 14(6): 469-473.

[4] Yang S. L. Numerical simulation of 3-dimensional dust distribution on long wall coal faces[J]. China Safety Science Journal, 2001, 11(4): 61-64.

[5] Liu Y., Jiang Z. A., Cai W., et al. Site measurement and digital simulation of dust density distribution in fully mechanized long wall coal mining face[J]. Coal Science and Technology, 2006, 34(4): 80-82.

[6] Wang X. Z., Jiang Z. A., Wang S. W., et al. Numerical simulation of distribution regularities of dust concentration during the ventilation process of coal roadway driving[J]. Journal of China Coal Society, 2007, 32(4): 386-390.

[7] Zhang J., Wang X. L., Chen H. C., et al. Simulation on ventilation and dust diffusion on heading face of the diversion tunnel[J]. Journal of Hydroelectric Engineering, 2008, 27(1): 111-117.

[8] Gosman A. D., Issa R. I., Lekakou C., et al. Multidimensional modeling of turbulent two-phase flows in stirred vessels[J] AIChE Journal, 1992, 38(12): 1946-1956.

[9] Auton T. R., Hunt J. C. R. Prud’homme. The force exerted on a body in inviscid unsteady non-uniform rotational flow[J]. The Journal of Fluid Mechanics, 1988, 197 241-257.

[10] Lance M., Bateille J. Turbulence in liquid and phase of a uniform bubbly air-water flow[J]. Journal of Fluid Mechanics, 1991, 222(1): 95-118.

[11] Launder B. E., Spalding D. B. The numerical computation of turbulent flows[J]. Computer Methods and Engineering, 1974, 3(2): 269-289.

[12] Rodi W. Influence of buoyancy and rotation on equations for the turbulent length scale[C]. In: Proc 2nd Symp on Turbulent Shear Flows. Imperial College of London, 1979.

[13] El Tahry S. H. k-ɛ equation for compressible reciprocating engine flows[J]. AIAA J Energy, 1983, 7(4): 345-353.

[14] Nakayama S., Uchino K., Inoue M. 3 dimensional flow measurement at heading face and application of CFD dimensional flow measurement at heading face and application of CFD[J]. Journal of the Mining and Materials processing, 1996, 112(9): 639-644.

[15] Tao W. Q. Numerical Heat Transfer[M]. 2001 2 Xi’an: Xi’an Jiaotong University Press.

[16] Cebeci T., Bradshaw P. Momentum Transfer in Boundary Layers[M]. 1977, New York: Hemisphere Publishing Corporation.