Investigation of k-ε Turbulent Models and Their Effects on Offset Jet Flow Simulation

Mohammad Reza Boroomand, Amirhossein Mohammadi

Abstract


In the case in which relatively low thickness and high-velocity flow enter into the lower velocity fluid, the resulting interference field of these two flows is called the jet. This phenomenon is the dominant output of power plants and some of the dams. The jets can be divided into two categories of free jets and confined jets, caused by the distance from the discharge to limited boundaries points. The offset jet is a type of confined jet in which both free surface and wall boundaries are near the diffusion location. The jet flow due to the extreme curvature in the main flow path and the proximal portion of this flow with solid boundaries have characteristics that make it difficult to solve with simple turbulence models.

In this research, the offset jet phenomenon and related issues have been investigated. For this purpose, the offset jet flow pattern and probable factors in the complexity of this model have been simulated using Fluent software which analyses fluid flow in a two dimensional and three dimensional finite volume method. The simulation of offset jet flow pattern has been performed with a focus on investigating different models of turbulence k-ε, also boundary conditions, various wall functions and other effective coefficients in the numerical model and the model results compared with test case data findings and validating results, the necessary approaches in numerical simulation of this phenomenon for using in the next stages had been taken.


Keywords


k-ε; Turbulence; Offset Jet; Numerical Simulation.

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References


M.R. Boroomand, A. A. Salehi-Neyshaboury, K. Aghajanloo. “Numerical Simulation of Sediment Transport and Scouring by an Offset Jet” Canadian Journal of Civil Eng 34 (2007) 1267-1275. doi: 10.1139/l07-050.

A. Nasr, J. Lai, “A Turbulent Plane Offset Jet with Small Offset Ratio” Experiments in Fluids 24 (1998) 47–57. doi: 10.1007/s003480050149.

C. Bourque, B. G. Newman, “Reattachment of a Tow-Dimensional Incompressible Jet to an Adjacent Flat Plate” Aeronautical Quarterly 11 (2016) 201-232.doi: 10.1017/s0001925900001797.

R. A. Sawyer, “The Flow Due to a 2D Jet Issuing Parallel to a Flat Plate” Journal of Fluid Mechanic 9 (1960) 543-561.doi: 10.1017/s0022112060001304.

D. I. McRee, H. I. Moses, “The Effect of Aspect Ratio and Offset Ratio on Nozzle Flow and Jet Reattachment” Advances in Fluids, ASME Press, New York, 1967, pp. 142-161.

C. C. Perry, “Two-Dimensional Jet Reattachment” PhD thesis, University of Michigan, Michigan, 1967.

N. Rajaratnam, N. Subramanya, “Plane Turbulent Reattachment Wall Jet” Journal of Hydraulic Division, 1968, (94) 95-112.

K. Ayukawa, T. Shakouchi. “Analysis of a Jet Attaching to an Offset Parallel Plate” Bulletin of the JSME 19 (130) 395-401.doi: 10.1299/jsme1958.19.395.

A. J. Johnston, “Experimental Study of Shallow Submerged Turbulent Jets”, Ph. D Thesis, University of Liverpool, Liverpool, 1978.

T. Nozaki, K. Hatta, N. Satu, H. Matsumua, “Reattachment Flow Issuing From a Finite Nozzle” Bulletin of The JSME 24 (1981) 363-369.doi: 10.1299/jsme1958.24.363.

J. Hoch, M. Jiji, “Tow-Dimensional Turbulent Offset Jet Boundary Interaction”, Transactions of The ASME, Journal of Fluids Engineering 103 (1981) 154-161.doi: 10.1115/1.3240766.

A. A. Salehi Neyshabouri, “Impingement of Offset Jets on Rigid and Movable Beds” Ph. D Thesis, University of Liverpool, Liverpool, 1988.

A. A. Salehi Neyshabouri, K. H. M. Ali, “Flow Field of an Offset Jet” Proceedings of the International Conference on Physical Modeling of Transport and Dispersion, Massachusetts, Cambridge University Press , 1990, pp.13-18.

D. S. Kim, S. H. Yoon, D. H. Lee, K. CH. Kim, “Flow and Heat Transfer Measurements of a Wall Attaching Offset Jet” International Journal of Heat Mass Transfer 39 (1996) 2910-2913.doi: 10.1016/j.ijheatmasstransfer.2014.07.008.

H. B. Song, S. H. Yoon, D. H. Lee, “Flow and Heat Transfer Characteristics of a Two-Dimensional Oblique Wall Attaching Offset Jet” International Journal of Heat and Mass Transfer 43 (2000) 2395-2404.doi: 10.1016/s0017-9310(99)00312-9.

M. Miozzi, F. Lalli, G. P. Romano, “Experimental investigation of a free-surface turbulent jet with Coanda effect” Experiments in Fluids 49 (2010) 341-353.doi: 10.1007/s00348-010-0885-1.

Ali Assoudi, A., S. Habli, N. M. Saïd , H. Bournot, and G. Le Palec, “Experimental and numerical study of an offset jet with different velocity and offset ratios”, Engineering Applications of Computational Fluid Mechanics (2015): 490–512.doi: 10.1080/19942060.2015.1071525

Ali Assoudi, A., S. Habli, N. M. Saïd , H. Bournot, and G. Le Palec, “Three-dimensional study of turbulent flow characteristics of an offset plane jet with variable density”, International Journal of Heat and Mass Transfer 52 (2016) 2327–2343.doi: 10.1007/s00231-015-1750-9.

Mohammadaliha, N., H. Afshin, and B. Farahanieh, “Numerical Investigation of Nozzle Geometry Effect onTurbulent 3-D Water Offset Jet Flows” Journal of Applied Fluid Mechanics 9 (2016): 2083-2095. doi: 10.18869/acadpub.jafm.68.235.21386.

Balázs, B., and Z. Szánthó, , “Experimental and Numerical Investigation of an Offset Jet Using Tangential Air Distribution System”, Periodica Polytechnica Mechanical Engineering (2016): 129–136.doi: 10.3311/PPme.8017.

Wu W., Rodi W., Wenka T., “3D Numerical Modeling of Flow And Sediment Transport In Open Channel” Journal of Hydraulic Engineering, Vol. 126, No. 1, 2000.doi: 10.1061/(asce)0733-9429(2000)126:1(4).




DOI: https://doi.org/10.28991/cej-2019-03091231

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