0
Research Papers: Fundamental Issues and Canonical Flows

Investigation in the Near-Field of a Row of Interacting Jets

[+] Author and Article Information
Shahriar Ghahremanian

Department of Building, Energy
and Environmental Engineering,
Faculty of Engineering and
Sustainable Development,
University of Gävle,
Gävle 801 76, Sweden
Division of Energy Systems,
Department of Management and Engineering,
Linköping University,
Linköping 581 83, Sweden
e-mail: shahriar.ghahremanian@liu.se

Bahram Moshfegh

Department of Building, Energy
and Environmental Engineering,
Faculty of Engineering and
Sustainable Development,
University of Gävle,
Gävle 801 76, Sweden
Division of Energy Systems,
Department of Management and Engineering,
Linköping University,
Linköping 581 83, Sweden
e-mail: bahram.moshfegh@hig.se

Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received December 9, 2014; final manuscript received June 4, 2015; published online August 6, 2015. Assoc. Editor: Samuel Paolucci.

J. Fluids Eng 137(12), 121202 (Aug 06, 2015) (18 pages) Paper No: FE-14-1738; doi: 10.1115/1.4031014 History: Received December 09, 2014

Multiple interacting jets (confluent jets) are employed in many engineering applications, and the significant design factors must be investigated. Computational fluid dynamics (CFD) is used to numerically predict the flow field in the proximal region of a single row of round jets. The numerical results that are obtained when using the low Reynolds k-ε are validated with the experimental data that are acquired by particle image velocimetry (PIV). PIV was used to measure mean velocity and turbulence properties in the proximal region of a row of six parallel coplanar round air jets with equidistant spacing at low Reynolds number (Re = 3290). The low Reynolds k-ε underpredicts the streamwise velocity in the onset of the jets' decay. The characteristic points are determined for various regions between two neighboring jets. The comparison of the merging point (MP) and the combined point (CP) computed from measurements and simulations shows good agreement in the different regions between the jets. In this study, a computational parametric study is also conducted to determine the main effects of three design factors and the interactions between them on the flow field development using response surface method (RSM). The influences of the inlet velocity, the spacing between the nozzles, and the diameter of the nozzles on the locations of the characteristic points are presented in the form of correlations (regression equations). CFD is used to numerically predict the characteristic points for a set of required studies, for which the design values of the simulation cases are determined by the Box–Behnken method. The results indicate that the spacing between the nozzles has a major impact on the flow characteristics in the near-field region of multiple interacting jets. The RSM shows that the inlet velocity has a marginal effect on the merging and CPs. All of the square terms are removed from the response equations of MP, and only one two-way interaction term between inlet velocity and spacing remains in the regression model with a marginal effect. The square of the nozzle diameter contributes in the regression equations of CP in some regions between the jets.

Copyright © 2015 by ASME
Your Session has timed out. Please sign back in to continue.

References

Tanaka, E. , 1970, “The Interference of Two-Dimensional Parallel Jets: 1st Report, Experiments on Dual Jet,” Bull. JSME, 13(56), pp. 272–280. [CrossRef]
Awbi, H. B. , 2003, Ventilation of Buildings, Spon Press, New York.
Cho, Y. , Awbi, H. B. , and Karimipanah, T. , 2008, “Theoretical and Experimental Investigation of Wall Confluent Jets Ventilation and Comparison With Wall Displacement Ventilation,” Build. Environ., 43(6), pp. 1091–1100. [CrossRef]
Janbakhsh, S. , Moshfegh, B. , and Ghahremanian, S. , 2010, “A Newly Designed Supply Diffuser for Industrial Premises,” Int. J. Vent., 9(1), pp. 59–68.
Ghahremanian, S. , and Moshfegh, B. , 2014, “Evaluation of RANS Models in Predicting Low Reynolds, Free, Turbulent Round Jet,” ASME J. Fluids Eng., 136(1), pp. 1–13.
Olsson, M. , and Fuchs, L. , 1996, “Large Eddy Simulation of the Proximal Region of a Spatially Developing Circular Jet,” Phys. Fluids, 8(8), pp. 2125–2137. [CrossRef]
Quinn, W. R. , and Militzer, J. , 1989, “Effects of Nonparallel Exit Flow on Round Turbulent Free Jets,” Int. J. Heat Fluid Flow, 10(2), pp. 139–145. [CrossRef]
Mi, J. , Nathan, G. J. , and Nobes, D. S. , 2001, “Mixing Characteristics of Axisymmetric Free Jets From a Contoured Nozzle, an Orifice Plate and a Pipe,” ASME J. Fluids Eng., 123(4), pp. 878–883. [CrossRef]
Sami, S. , Carmody, T. , and Rouse, H. , 1967, “Jet Diffusion in the Region of Flow Establishment,” J. Fluid Mech., 27(2), pp. 231–252. [CrossRef]
Hill, B. J. , 1972, “Measurement of Local Entrainment Rate in the Initial Region of Axisymmetric Turbulent Air Jets,” J. Fluid Mech., 51(4), pp. 773–779. [CrossRef]
Boguslawski, L. , and Popiel, C. O. , 1979, “Flow Structure of the Free Round Turbulent Jet in the Initial Region,” J. Fluid Mech., 90(3), pp. 531–539. [CrossRef]
Obot, N. T. , Graska, M. L. , and Trabold, T. A. , 1984, “The Near Field Behavior of Round Jets at Moderate Reynolds Numbers,” Can. J. Chem. Eng., 62(5), pp. 587–593. [CrossRef]
Ball, C. G. , Fellouah, H. , and Pollard, A. , 2012, “The Flow Field in Turbulent Round Free Jets,” Prog. Aeosp. Sci., 50, pp. 1–26. [CrossRef]
Wygnanski, I. , and Fiedler, H. , 1969, “Some Measurements in the Self-Preserving Jet,” J. Fluid Mech., 38(3), pp. 577–612. [CrossRef]
Rodi, W. , 1975, “A New Method of Analysing Hot-Wire Signals in Highly Turbulent Flow, and Its Evaluation in a Round Jet,” DISA Inf., 17, pp. 9–18.
Panchapakesan, N. R. , and Lumley, J. L. , 1993, “Turbulence Measurements in Axisymmetric Jets of Air and Helium. Part 1: Air Jet,” J. Fluid Mech., 246(1), pp. 197–223. [CrossRef]
Hussein, J. H. , Capp, S. P. , and George, W. K. , 1994, “Velocity Measurements in a High-Reynolds-Number, Momentum-Conserving, Axisymmetric, Turbulent Jet,” J. Fluid Mech., 258, pp. 31–75. [CrossRef]
Ewing, D. , Frohnapfel, B. , George, W. K. , Pedersen, J. M. , and Westerweel, J. , 2007, “Two-Point Similarity in the Round Jet,” J. Fluid Mech., 577, pp. 309–330. [CrossRef]
Miller, D. R. , and Comings, E. W. , 1960, “Force-Momentum Fields in a Dual-Jet Flow,” J. Fluid Mech., 7(2), pp. 237–256. [CrossRef]
Tanaka, E. , 1974, “The Interference of Two-Dimensional Parallel Jets: 2nd Report, Experiments on the Combined Flow of Dual Jet,” Bull. JSME, 17(109), pp. 920–927. [CrossRef]
Okamoto, T. , Yagita, M. , Watanabe, A. , and Kawamura, K. , 1985, “Interaction of Twin Turbulent Circular Jet,” Bull. JSME, 28(238), pp. 617–622. [CrossRef]
Yin, Z. , Zhang, H. , and Lin, J. , 2007, “Experimental Study on the Flow Field Characteristics in the Mixing Region of Twin Jets,” J. Hydrodyn., Ser. B, 19(3), pp. 309–313. [CrossRef]
Nasr, A. , and Lai, J. C. S. , 1997, “Two Parallel Plane Jets: Mean Flow and Effects of Acoustic Excitation,” Exp. Fluids, 22(3), pp. 251–260. [CrossRef]
Vouros, A. , and Panidis, T. , 2008, “Influence of a Secondary, Parallel, Low Reynolds Number, Round Jet on a Turbulent Axisymmetric Jet,” Exp. Therm. Fluid Sci., 32(8), pp. 1455–1467. [CrossRef]
Fujisawa, N. , Nakamura, K. , and Srinivas, K. , 2004, “Interaction of Two Parallel Plane Jets of Different Velocities,” J. Visualization, 7(2), pp. 135–142. [CrossRef]
Anderson, E. A. , and Spall, R. E. , 2001, “Experimental and Numerical Investigation of Two-Dimensional Parallel Jets,” ASME J. Fluids Eng., 123(2), pp. 401–406. [CrossRef]
Durve, A. , Patwardhan, A. W. , Banarjee, I. , Padmakumar, G. , and Vaidyanathan, G. , 2012, “Numerical Investigation of Mixing in Parallel Jets,” Nucl. Eng. Des., 242, pp. 78–90. [CrossRef]
Corrsin, S. , 1944, “Investigation of the Behavior of Parallel Two-Dimensional Air Jets,” NASA, Report No. 4H24.
Knystautas, R. , 1962, “The Turbulent Jet From a Series of Holes in Line,” McGill University, Montréal, Canada, MERL Report No. 62-1.
Marsters, G. F. , 1979, “Measurements in the Flow Field of a Linear Array of Rectangular Nozzles,” J. Aircr., 17(11), pp. 774–780. [CrossRef]
Pani, B. , and Dash, R. , 1983, “Three-Dimensional Single and Multiple Free Jets,” J. Hydraul. Eng., 109(2), pp. 254–269. [CrossRef]
Villermaux, E. , and Hopfinger, E. J. , 1994, “Periodically Arranged Co-Flowing Jets,” J. Fluid Mech., 263, pp. 63–92. [CrossRef]
Larraona, G. S. , Rivas, A. , Antón, R. , Ramos, J. C. , Pastor, I. , and Moshfegh, B. , 2013, “Computational Parametric Study of an Impinging Jet in a Cross-Flow Configuration for Electronics Cooling Applications,” Appl. Therm. Eng., 52(2), pp. 428–438. [CrossRef]
Bell, J. H. , and Mehta, R. D. , 1988, “Contraction Design for Small Low-Speed Wind Tunnels,” National Aeronautics and Space Administration, AMES Research Center; Stanford University, Department of Aeronautics and Astronautics, Joint Institute for Aeronautics and Acoustics, Report No. NASA CR-182747.
Bell, J. H. , and Mehta, R. D. , 1989, “Boundary-Layer Predictions for Small Low-Speed Contractions,” AIAA J., 27(3), pp. 372–374. [CrossRef]
Ghahremanian, S. , Svensson, K. , Tummers, M. J. , and Moshfegh, B. , 2014, “Near-Field Development of a Row of Round Jets at Low Reynolds Numbers,” Exp. Fluids, 55(8), pp. 1–18. [CrossRef]
Ghahremanian, S. , and Moshfegh, B. , 2014, “A Study on Proximal Region of Low Reynolds Confluent Jets. Part 1: Evaluation of Turbulence Models in Prediction of Inlet Boundary Conditions,” ASHRAE Trans., 120(1), pp. 256–270.
Ghahremanian, S. , and Moshfegh, B. , 2014, “A Study on Proximal Region of Low Reynolds Confluent Jets. Part 2: Numerical Verification of the Flow Field,” ASHRAE Trans., 120(1), pp. 271–285.
Adrian, R. J. , and Westerweel, J. , 2010, Particle Image Velocimetry, Cambridge University Press, New York.
Khuri, A. I. , and Mukhopadhyay, S. , 2010, “Response Surface Methodology,” Wiley Interdiscip. Rev.: Comput. Stat., 2(2), pp. 128–149. [CrossRef]
Ferreira, S. L. C. , Bruns, R. E. , Ferreira, H. S. , Matos, G. D. , David, J. M. , Brandão, G. C. , da Silva, E. G. P. , Portugal, L. A. , dos Reis, P. S. , Souza, A. S. , and dos Santos, W. N. L. , 2007, “Box-Behnken Design: An Alternative for the Optimization of Analytical Methods,” Anal. Chim. Acta, 597(2), pp. 179–186. [CrossRef] [PubMed]
Todde, V. , Spazzini, P. G. , and Sandberg, M. , 2009, “Experimental Analysis of Low-Reynolds Number Free Jets: Evolution Along the Jet Centerline and Reynolds Number Effects,” Exp. Fluids, 47(2), pp. 279–294. [CrossRef]
Knystautas, R. , 1964, “The Turbulent Jet From a Series of Holes in Line,” Aeronaut. Q., 15, pp. 1–28.
Launder, B. E. , and Sharma, B. I. , 1974, “Application of the Energy-Dissipation Model of Turbulence to the Calculation of Flow Near a Spinning Disc,” Lett. Heat Mass Transfer, 1(2), pp. 131–137. [CrossRef]
Ghahremanian, S. , and Moshfegh, B. , 2011, “Numerical and Experimental Verification of Initial, Transitional and Turbulent Regions of Free Turbulent Round Jet,” AIAA Paper No. 2011-3697.
Pope, S. B. , 1978, “An Explanation of the Turbulent Round-Jet/Plane-Jet Anomaly,” AIAA J., 16(3), pp. 279–281. [CrossRef]
Wilcox, D. C. , 2010, Turbulence Modeling for CFD, DCW Industries, La Cañada Flintridge, CA.
Ghahremanian, S. , Svensson, K. , Tummers, M. J. , and Moshfegh, B. , 2014, “Near-Field Mixing of Jets Issuing From an Array of Round Nozzles,” Int. J. Heat Fluid Flow, 47, pp. 84–100. [CrossRef]
Nasr, A. , and Lai, J. C. S. , 1997, “Comparison of Flow Characteristics in the Near Field of Two Parallel Plane Jets and an Offset Plane Jet,” Phys. Fluids, 9(10), pp. 2919–2931. [CrossRef]
Yimer, I. , Becker, H. A. , and Grandmaison, E. W. , 1996, “Development of Flow From Multiple-Jet Burners,” Can. J. Chem. Eng., 74(6), pp. 840–851. [CrossRef]
Lin, Y. F. , and Sheu, M. J. , 1990, “Investigation of Two Plane Parallel Unventilated Jets,” Exp. Fluids, 10(1), pp. 17–22. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Top-view sketch of the wind tunnel, test chamber, and instrumentation

Grahic Jump Location
Fig. 2

Location of the PIV measurement and the nozzle shape geometry

Grahic Jump Location
Fig. 3

Computational domain and nozzle shape of the validation case

Grahic Jump Location
Fig. 4

Decay of the streamwise velocity along the geometrical centerline of CJ I (left) and CJ II (right)

Grahic Jump Location
Fig. 5

Streamwise velocity (V/Vb) at different distances from the nozzles edge

Grahic Jump Location
Fig. 6

Contour plot of the velocity magnitude ((U2+V2)/Vb) in the geometrical center-plane (z = 0) measured by the PIV (left) and predicted by the low Re kϵ (right)

Grahic Jump Location
Fig. 7

Residual plots of CP1 in the region II–SJ before stepwise regression, normal probability plot of residuals (top left), residuals versus fits (top right), histogram of residuals (bottom left), and residuals for each test case (bottom right)

Grahic Jump Location
Fig. 8

Residual plots of MP in the region II–SJ after using the backward elimination method, the normal probability plot of the residuals (top left), the residuals versus the fits (top right), the histogram of the residuals (bottom left), and the residuals for each test case (bottom right)

Grahic Jump Location
Fig. 9

Comparison of numerically predicted (CFD) and statistically estimated (RSM) characteristic points (MP: top, CP1: middle, and CP2: bottom) versus the airflow rate, Q (m3/s)

Grahic Jump Location
Fig. 10

Comparison of the numerically predicted (CFD) and statistically estimated (RSM) characteristic points (MP: top, CP1: middle, and CP2: bottom) versus S/d

Grahic Jump Location
Fig. 11

Comparison of the numerically predicted (CFD) and statistically estimated (RSM) characteristic points (MP: top, CP1: middle, and CP2: bottom) versus the Reynolds number

Grahic Jump Location
Fig. 12

Contour (top) and surface (bottom) plot of MP (m) in various regions (I–I and II–SJ) versus S – V (left, d  = 0.007 m), d – V (middle, S  = 0.014 m), and d – S (right, V  = 12 m/s)

Grahic Jump Location
Fig. 13

Contour plot of the CP1 (m) in regions I–I (left), I–II (middle), and II–SJ (right) versus d – S (top, V  = 10 m/s), d – V (middle, S  = 0.014 m), and S – V (bottom, d  = 0.009 m)

Grahic Jump Location
Fig. 14

Surface plot of CP1 (m) in regions I–I (left), I–II (middle), and II–SJ (right) versus d – S (top, V  = 10 m/s), d – V (middle, S  = 0.014 m), and S – V (bottom, d  = 0.009 m)

Grahic Jump Location
Fig. 15

Contour plot of CP2 (m) in regions I–I (left), I–II (middle), and II–SJ (right) versus d – S (top, V  = 8 m/s), d – V (middle, S  = 0.012 m), and S – V (bottom, d  = 0.009 m)

Grahic Jump Location
Fig. 16

Surface plot of CP2 (m) in regions I–I (left), I–II (middle), and II–SJ (right) versus d – S (top, V = 8 m/s), d – V (middle, S = 0.012 m), and S – V (bottom, d = 0.009 m)

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In