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Volumn 127, Issue 5, 2005, Pages 544-552

Impingement heat transfer: Correlations and numerical modeling

Author keywords

[No Author keywords available]

Indexed keywords

COMPUTER SIMULATION; JETS; MATHEMATICAL MODELS; NUMERICAL ANALYSIS; REYNOLDS NUMBER; SHEAR STRESS; TURBINES;

EID: 22744447182     PISSN: 00221481     EISSN: None     Source Type: Journal    
DOI: 10.1115/1.1861921     Document Type: Review
Times cited : (314)

References (54)
  • 1
    • 0037431482 scopus 로고    scopus 로고
    • "An Evaluation of Gas Quenching of Steel Rings by Multiple-jet Impingement"
    • Ferrari, J., Lior, N., and Slycke, J., 2003, "An Evaluation of Gas Quenching of Steel Rings by Multiple-jet Impingement," J. Mater. Process. Technol., 136(1-3), pp. 190-201.
    • (2003) J. Mater. Process. Technol. , vol.136 , Issue.1-3 , pp. 190-201
    • Ferrari, J.1    Lior, N.2    Slycke, J.3
  • 2
    • 34548506954 scopus 로고
    • "Heat and Mass Transfer between Impinging Gas Jets and Solid Surfaces"
    • Martin, H., 1977, "Heat and Mass Transfer between Impinging Gas Jets and Solid Surfaces," Adv. Heat Transfer, 13, pp. 1-60.
    • (1977) Adv. Heat Transfer , vol.13 , pp. 1-60
    • Martin, H.1
  • 3
    • 0026883597 scopus 로고
    • "A Review of Heat Transfer Data for Single Circular Jet Impingement"
    • Jambunathan, K., Lai, E., Moss, M. A., and Button, B. L., 1992, "A Review of Heat Transfer Data for Single Circular Jet Impingement," Int. J. Heat Fluid Flow, 13(2), pp. 106-115.
    • (1992) Int. J. Heat Fluid Flow , vol.13 , Issue.2 , pp. 106-115
    • Jambunathan, K.1    Lai, E.2    Moss, M.A.3    Button, B.L.4
  • 4
    • 84928153194 scopus 로고
    • "A Study of Free Jet Impingement. Mean Properties of Free and Impinging Jets"
    • Donaldson, C. D., and Snedeker, R. S., 1971, "A Study of Free Jet Impingement. Part 1. Mean Properties of Free and Impinging Jets," J. Fluid Mech., 45(2), pp. 281-319.
    • (1971) J. Fluid Mech. , vol.45 , Issue.2 PART 1 , pp. 281-319
    • Donaldson, C.D.1    Snedeker, R.S.2
  • 5
    • 0027545215 scopus 로고
    • "Heat Transfer to Impinging Isothermal Gas and Flame Jets"
    • Viskanta, R., 1993, "Heat Transfer to Impinging Isothermal Gas and Flame Jets," Exp. Therm. Fluid Sci., 6, pp. 111-134.
    • (1993) Exp. Therm. Fluid Sci. , vol.6 , pp. 111-134
    • Viskanta, R.1
  • 7
    • 0034227971 scopus 로고    scopus 로고
    • "Power Generation Analysis for High Temperature Gas Turbine in Thermodynamic Process"
    • Taniguchi, H., Miyamae, S., Arai, N., and Lior, N., 2000, "Power Generation Analysis for High Temperature Gas Turbine in Thermodynamic Process," AIAA J., 16, pp. 557-561.
    • (2000) AIAA J. , vol.16 , pp. 557-561
    • Taniguchi, H.1    Miyamae, S.2    Arai, N.3    Lior, N.4
  • 8
    • 0033930917 scopus 로고    scopus 로고
    • "The Effect of Nozzle Configuration on Stagnation Region Heat Transfer Enhancement of Axisymmetric Jet Impingement"
    • Lee, J., and Lee, S, 2000, "The Effect of Nozzle Configuration on Stagnation Region Heat Transfer Enhancement of Axisymmetric Jet Impingement," Int. J. Heat Mass Transfer, 43, pp. 3497-3509.
    • (2000) Int. J. Heat Mass Transfer , vol.43 , pp. 3497-3509
    • Lee, J.1    Lee, S.2
  • 10
    • 0026913828 scopus 로고
    • "Flow and Heat Transfer to a Circular Cylinder with a Hot Impinging Jet"
    • Kang, S. H., and Greif, R., 1992, "Flow and Heat Transfer to a Circular Cylinder with a Hot Impinging Jet," Int. J. Heat Mass Transfer, 35, pp. 2173-2183.
    • (1992) Int. J. Heat Mass Transfer , vol.35 , pp. 2173-2183
    • Kang, S.H.1    Greif, R.2
  • 11
    • 0036937525 scopus 로고    scopus 로고
    • "Large Eddy Simulation of a Plane Impinging Jet"
    • Beaubert, F., and Viazzo, S., 2002, "Large Eddy Simulation of a Plane Impinging Jet," C. R. Mecanique, 330, pp. 803-810.
    • (2002) C. R. Mecanique , vol.330 , pp. 803-810
    • Beaubert, F.1    Viazzo, S.2
  • 12
    • 0029389315 scopus 로고
    • "Large-eddy Simulation of Turbulent Heat Transport in Enclosed Impinging Jets"
    • Gao, S., and Voke, P. R., 1995, "Large-eddy Simulation of Turbulent Heat Transport in Enclosed Impinging Jets," Int. J. Heat Fluid Flow, 16, pp. 349-356.
    • (1995) Int. J. Heat Fluid Flow , vol.16 , pp. 349-356
    • Gao, S.1    Voke, P.R.2
  • 13
    • 21544482114 scopus 로고    scopus 로고
    • "Numerical Study of Impinging Jets with Heat Transfer"
    • Licentiate Thesis, Royal Institute of Technology, Stockholm, Sweden
    • Hällqvist, T., 2003, "Numerical Study of Impinging Jets with Heat Transfer," Licentiate Thesis, Royal Institute of Technology, Stockholm, Sweden.
    • (2003)
    • Hällqvist, T.1
  • 14
    • 0032004091 scopus 로고    scopus 로고
    • "Large Eddy Simulations of a Forced Semiconfined Circular Impinging Jet"
    • Olsson, M., and Fuchs, L., 1998, "Large Eddy Simulations of a Forced Semiconfined Circular Impinging Jet," Phys. Fluids, 10(2), pp. 476-486.
    • (1998) Phys. Fluids , vol.10 , Issue.2 , pp. 476-486
    • Olsson, M.1    Fuchs, L.2
  • 15
    • 0035479186 scopus 로고    scopus 로고
    • "Large-Eddy Simulation of Flow and Heat Transfer in an Impinging Slot Jet"
    • Cziesla, T., Biswas, G., Chattopadhyay, H., and Mitra, N. K., 2001, "Large-Eddy Simulation of Flow and Heat Transfer in an Impinging Slot Jet," Int. J. Heat Fluid Flow, 22, pp. 500-508.
    • (2001) Int. J. Heat Fluid Flow , vol.22 , pp. 500-508
    • Cziesla, T.1    Biswas, G.2    Chattopadhyay, H.3    Mitra, N.K.4
  • 17
    • 0027628293 scopus 로고
    • "Impinging Jet Studies for Turbulence Model Assessment - II. An Examination of the Performance of Four Turbulence Models"
    • Craft, T. J., Graham, L. J. W., and Launder, B. E., 1993, "Impinging Jet Studies for Turbulence Model Assessment - II. An Examination of the Performance of Four Turbulence Models," Int. J. Heat Mass Transfer, 36, pp. 2685-2697.
    • (1993) Int. J. Heat Mass Transfer , vol.36 , pp. 2685-2697
    • Craft, T.J.1    Graham, L.J.W.2    Launder, B.E.3
  • 18
    • 0031467335 scopus 로고    scopus 로고
    • "Numerical Study of the Wall Shear Stress Produced by the Impingement of a Plane Turbulent Jet on a Plate"
    • Bouainouche, M., Bourabaa, N., Desmet, B., 1997, "Numerical Study of the Wall Shear Stress Produced by the Impingement of a Plane Turbulent Jet on a Plate," Int. J. Numer. Methods Heat Fluid Flow, 7, pp. 548-564.
    • (1997) Int. J. Numer. Methods Heat Fluid Flow , vol.7 , pp. 548-564
    • Bouainouche, M.1    Bourabaa, N.2    Desmet, B.3
  • 19
    • 0030214591 scopus 로고    scopus 로고
    • "Heat Transfer in Separated and Impinging Turbulent Flows"
    • Heyerichs, K., and Pollard, A., 1996, "Heat Transfer in Separated and Impinging Turbulent Flows," Int. J. Heat Mass Transfer, 39, pp. 2385-2400.
    • (1996) Int. J. Heat Mass Transfer , vol.39 , pp. 2385-2400
    • Heyerichs, K.1    Pollard, A.2
  • 20
    • 0027628292 scopus 로고
    • "Impinging Jet Studies for Turbulence Model Assessment - I. Flow-field Experiments"
    • Cooper, D., Jackson, C., Launder, B. E., and Liao, G. X., 1993, "Impinging Jet Studies for Turbulence Model Assessment - I. Flow-field Experiments," Int. J. Heat Mass Transfer, 36, pp. 2675-2684.
    • (1993) Int. J. Heat Mass Transfer , vol.36 , pp. 2675-2684
    • Cooper, D.1    Jackson, C.2    Launder, B.E.3    Liao, G.X.4
  • 21
    • 0030130491 scopus 로고    scopus 로고
    • "Development and Application of a Cubic Eddy-Viscosity Model of Turbulence"
    • Craft, T. J., Launder, B. E., and Suga, K., 1996, "Development and Application of a Cubic Eddy-Viscosity Model of Turbulence," Int. J. Heat Fluid Flow, 17, pp. 108-115.
    • (1996) Int. J. Heat Fluid Flow , vol.17 , pp. 108-115
    • Craft, T.J.1    Launder, B.E.2    Suga, K.3
  • 22
    • 0035596377 scopus 로고    scopus 로고
    • "Verification and Validation of Adaptive Finite Element Method for Impingement Heat Transfer"
    • Turgeon, E., and Pelletier, D., 2001, "Verification and Validation of Adaptive Finite Element Method for Impingement Heat Transfer," J. Thermophys. Heat Transfer, 15, pp. 284-292.
    • (2001) J. Thermophys. Heat Transfer , vol.15 , pp. 284-292
    • Turgeon, E.1    Pelletier, D.2
  • 23
    • 0037268775 scopus 로고    scopus 로고
    • "Numerical Simulation of Heat Transfer of Turbulent Impinging Jets with Two-Equation Turbulence Models"
    • Merci, B., Vierendeels, I., DeLange, C., and Dick, E., 2003, "Numerical Simulation of Heat Transfer of Turbulent Impinging Jets with Two-Equation Turbulence Models," Int. J. Numer. Methods Heat Fluid Flow, 13, pp. 110-132.
    • (2003) Int. J. Numer. Methods Heat Fluid Flow , vol.13 , pp. 110-132
    • Merci, B.1    Vierendeels, I.2    DeLange, C.3    Dick, E.4
  • 24
    • 0036577030 scopus 로고    scopus 로고
    • "Study of Impinging Turbulent Jet Flows Using the Isotropic Low-Reynolds Number and the Algebraic Stress Methods"
    • Souris, N., Liakos, H., Founti, M., Palyvos, J., and Markatos, N., 2002, "Study of Impinging Turbulent Jet Flows Using the Isotropic Low-Reynolds Number and the Algebraic Stress Methods," Comput. Mech., 28, pp. 381-389.
    • (2002) Comput. Mech. , vol.28 , pp. 381-389
    • Souris, N.1    Liakos, H.2    Founti, M.3    Palyvos, J.4    Markatos, N.5
  • 27
    • 0141683855 scopus 로고    scopus 로고
    • "Streamline Upwind Numerical Simulation of Two-Dimensional Confined Impinging Slot Jets"
    • Park, T. H., Choi, H. G., Yoo, J. Y., and Kim, S. J., 2003, "Streamline Upwind Numerical Simulation of Two-Dimensional Confined Impinging Slot Jets," Int. J. Heat Mass Transfer, 46, pp. 251-262.
    • (2003) Int. J. Heat Mass Transfer , vol.46 , pp. 251-262
    • Park, T.H.1    Choi, H.G.2    Yoo, J.Y.3    Kim, S.J.4
  • 28
    • 0344628844 scopus 로고    scopus 로고
    • "Mass Transfer in Turbulent Impinging Slot Jet"
    • Chen, Q., and Modi, V., 1999, "Mass Transfer in Turbulent Impinging Slot Jets," Int. J. Heat Mass Transfer, 42, pp. 873-887.
    • (1999) Int. J. Heat Mass Transfer , vol.42 , pp. 873-887
    • Chen, Q.1    Modi, V.2
  • 29
    • 0029277647 scopus 로고
    • "A New k-ε Eddy-Viscosity Model for High Reynolds Number Turbulent Flows - Model Development and Validation"
    • Shih, T.-H., Liou, W. W., Shabbir, A., Yang, Z., and Zhu, J., 1995, "A New k-ε Eddy-Viscosity Model for High Reynolds Number Turbulent Flows - Model Development and Validation," Comput. Fluids, 24(3), pp. 227-238.
    • (1995) Comput. Fluids , vol.24 , Issue.3 , pp. 227-238
    • Shih, T.-H.1    Liou, W.W.2    Shabbir, A.3    Yang, Z.4    Zhu, J.5
  • 30
    • 0000017266 scopus 로고    scopus 로고
    • "Numerical Investigation of Impingement Heat Transfer using Linear and Nonlinear Two-Equation Turbulence Models"
    • Abdon, A,, and Sunden, B., 2001, "Numerical Investigation of Impingement Heat Transfer using Linear and Nonlinear Two-Equation Turbulence Models," Numer. Heat Transfer, Part A, 40, pp. 563-578.
    • (2001) Numer. Heat Transfer , vol.40 , Issue.PART A , pp. 563-578
    • Abdon, A.1    Sunden, B.2
  • 31
    • 0035241742 scopus 로고    scopus 로고
    • "Development of a Near-wall Turbulence Model and Application to Jet Impingement Heat Transfer"
    • Park, T. S., and Sung, H. J., 2001, "Development of a Near-wall Turbulence Model and Application to Jet Impingement Heat Transfer," Int. J. Heat Fluid Flow, 22, pp. 10-18.
    • (2001) Int. J. Heat Fluid Flow , vol.22 , pp. 10-18
    • Park, T.S.1    Sung, H.J.2
  • 33
    • 0346335507 scopus 로고    scopus 로고
    • "Systematic Numerical Studies on Heat Transfer and Aerodynamic Characteristics of Impingement Cooling Devices Combined with Pins"
    • 16-19 June 2003, Atlanta, GA
    • Funazaki, K., and Hachiya, K., 2003 "Systematic Numerical Studies on Heat Transfer and Aerodynamic Characteristics of Impingement Cooling Devices Combined with Pins," Proceedings of ASME Turbo Expo 2003, 16-19 June 2003, Atlanta, GA.
    • (2003) Proceedings of ASME Turbo Expo 2003
    • Funazaki, K.1    Hachiya, K.2
  • 34
    • 33044490295 scopus 로고
    • "Calculations of 3D Impinging Jets in Crossflow with Reynolds Stress Models"
    • R. J. Goldstein, D. E. Metzger, A. I. Leontiev, eds., Begell House, New York
    • Demuren, A. O., 1994, "Calculations of 3D Impinging Jets in Crossflow with Reynolds Stress Models," Heat Transfer in Turbomachinery, R. J. Goldstein, D. E. Metzger, A. I. Leontiev, eds., Begell House, New York, pp. 527-540.
    • (1994) Heat Transfer in Turbomachinery , pp. 527-540
    • Demuren, A.O.1
  • 35
    • 0037019691 scopus 로고    scopus 로고
    • "Computational Study of Impingement Heat Transfer under a Turbulent Slot Jet"
    • Shi, Y., Ray, M. B., and Mujumdar, A. S., 2002, "Computational Study of Impingement Heat Transfer under a Turbulent Slot Jet," Ind. Eng. Chem. Res., 41, pp. 4643-4651.
    • (2002) Ind. Eng. Chem. Res. , vol.41 , pp. 4643-4651
    • Shi, Y.1    Ray, M.B.2    Mujumdar, A.S.3
  • 36
    • 0032103511 scopus 로고    scopus 로고
    • "Prediction of Heat Transfer in an Axisymmetric Turbulent Jet Impinging on a Flat Plate"
    • Behnia, M., Parneix, S., Durbin, P. A., 1998, "Prediction of Heat Transfer in an Axisymmetric Turbulent Jet Impinging on a Flat Plate," Int. J. Heat Mass Transfer, 41, pp. 1845-1855.
    • (1998) Int. J. Heat Mass Transfer , vol.41 , pp. 1845-1855
    • Behnia, M.1    Parneix, S.2    Durbin, P.A.3
  • 37
    • 0033080530 scopus 로고    scopus 로고
    • "Numerical Study of Turbulent Heat Transfer in Confined and Unconfined Impinging Jets"
    • Behnia, M., Parneix, S., Shabany, Y., and Durbin, P. A., 1999, "Numerical Study of Turbulent Heat Transfer in Confined and Unconfined Impinging Jets," Int. J. Heat Fluid Flow, 20, pp. 1-9.
    • (1999) Int. J. Heat Fluid Flow , vol.20 , pp. 1-9
    • Behnia, M.1    Parneix, S.2    Shabany, Y.3    Durbin, P.A.4
  • 39
    • 0038469998 scopus 로고    scopus 로고
    • "Symmetry Breaking of Flow and Heat Transfer in Multiple Impinging Jets"
    • Thielen, L., Jonker, H. J. J., and Hanjalić, K., 2003, "Symmetry Breaking of Flow and Heat Transfer in Multiple Impinging Jets," Int. J. Heat Fluid Flow, 24, pp. 444-453.
    • (2003) Int. J. Heat Fluid Flow , vol.24 , pp. 444-453
    • Thielen, L.1    Jonker, H.J.J.2    Hanjalić, K.3
  • 40
    • 0003666450 scopus 로고    scopus 로고
    • "Zonal Two Equation k-ω Turbulence Models for Aerodynamic Flows"
    • AIAA-93-2906
    • Menter, F. R., "Zonal Two Equation k-ω Turbulence Models for Aerodynamic Flows," AIAA-93-2906.
    • Menter, F.R.1
  • 42
    • 0020182755 scopus 로고
    • "Impingement of a Circular Jet With and Without Crossflow"
    • Goldstein, R. J., and Behbahani, A. I., 1982, "Impingement of a Circular Jet With and Without Crossflow," Int. J. Heat Mass Transfer, 25, pp. 1377-1382.
    • (1982) Int. J. Heat Mass Transfer , vol.25 , pp. 1377-1382
    • Goldstein, R.J.1    Behbahani, A.I.2
  • 43
    • 0022766417 scopus 로고
    • "Streamwise Distribution of the Recovery Factor and the Local Heat Transfer Coefficient to an Impinging Circular Air Jet"
    • Goldstein, R. J., Behbahani, A. I., and Heppelmann, K. K., 1986, "Streamwise Distribution of the Recovery Factor and the Local Heat Transfer Coefficient to an Impinging Circular Air Jet," Int. J. Heat Mass Transfer, 29, pp. 1227-1235.
    • (1986) Int. J. Heat Mass Transfer , vol.29 , pp. 1227-1235
    • Goldstein, R.J.1    Behbahani, A.I.2    Heppelmann, K.K.3
  • 44
    • 0028486545 scopus 로고
    • "Air Jet Impingement Heat Transfer at low Nozzle-plate Spacings"
    • Lytle, D., and Webb, B. W., 1994, "Air Jet Impingement Heat Transfer at low Nozzle-plate Spacings," Int. J. Heat Mass Transfer, 37, pp. 1687-1697.
    • (1994) Int. J. Heat Mass Transfer , vol.37 , pp. 1687-1697
    • Lytle, D.1    Webb, B.W.2
  • 45
    • 0030199428 scopus 로고    scopus 로고
    • "Influence of Shear Layer Dynamics on Impingement Heat Transfer"
    • Meola, C., de Luca, L., and Carlomagno, G. M., 1996, "Influence of Shear Layer Dynamics on Impingement Heat Transfer," Exp. Therm. Fluid Sci., 13, pp. 29-37.
    • (1996) Exp. Therm. Fluid Sci. , vol.13 , pp. 29-37
    • Meola, C.1    de Luca, L.2    Carlomagno, G.M.3
  • 46
    • 0027579815 scopus 로고
    • "Heat Transfer Due to a Round Jet Impinging Normal to a Flat Surface"
    • Mohanty, A. K., and Tawfek, A. A., 1993, "Heat Transfer Due to a Round Jet Impinging Normal to a Flat Surface," Int. J. Heat Mass Transfer, 36, pp. 1639-1647.
    • (1993) Int. J. Heat Mass Transfer , vol.36 , pp. 1639-1647
    • Mohanty, A.K.1    Tawfek, A.A.2
  • 47
    • 0030285839 scopus 로고    scopus 로고
    • "Heat Transfer and Pressure Distributions of an Impinging Jet on a Flat Surface"
    • Tawfek, A. A., 1996, "Heat Transfer and Pressure Distributions of an Impinging Jet on a Flat Surface," Heat Mass Transfer, 32, pp. 49-54.
    • (1996) Heat Mass Transfer , vol.32 , pp. 49-54
    • Tawfek, A.A.1
  • 48
    • 0141457547 scopus 로고    scopus 로고
    • "An Impingement Cooling on a Flat Surface by Using Circular Jet with Longitudinal Swirling Strips"
    • Wen, M.-Y., and Jang, K.-J., 2003, "An Impingement Cooling on a Flat Surface by Using Circular Jet with Longitudinal Swirling Strips," Int. J. Heat Mass Transfer, 46(24), pp. 4657-4667.
    • (2003) Int. J. Heat Mass Transfer , vol.46 , Issue.24 , pp. 4657-4667
    • Wen, M.-Y.1    Jang, K.-J.2
  • 50
    • 0019563206 scopus 로고
    • "Streamwise Flow and Heat Transfer Distributions for Jet Array Impingement with Cross-flow"
    • Florschuetz, L. W., Truman, C. R., and Metzger, D. E., 1981, "Streamwise Flow and Heat Transfer Distributions for Jet Array Impingement with Cross-flow," ASME J. Heat Transfer, 103, pp. 337-342.
    • (1981) ASME J. Heat Transfer , vol.103 , pp. 337-342
    • Florschuetz, L.W.1    Truman, C.R.2    Metzger, D.E.3
  • 51
    • 0037402230 scopus 로고    scopus 로고
    • "Optimal Slot Height in the Jet Cooling of a Circular Cylinder"
    • Gori, F., and Bossi, L., 2003, "Optimal Slot Height in the Jet Cooling of a Circular Cylinder," Appl. Therm. Eng., 23, pp. 859-870.
    • (2003) Appl. Therm. Eng. , vol.23 , pp. 859-870
    • Gori, F.1    Bossi, L.2
  • 52
    • 0028671648 scopus 로고
    • "Effect of Jet-Jet Spacing on Convective Heat Transfer to Confined, Impinging Arrays of Axisymmetric Jets"
    • Huber, A. M., and Viskanta, R., 1994, "Effect of Jet-Jet Spacing on Convective Heat Transfer to Confined, Impinging Arrays of Axisymmetric Jets," Int. J. Heat Mass Transfer, 37, pp. 2859-2869.
    • (1994) Int. J. Heat Mass Transfer , vol.37 , pp. 2859-2869
    • Huber, A.M.1    Viskanta, R.2
  • 53
    • 0035806995 scopus 로고    scopus 로고
    • "Optimum Jet-to-Jet Spacing of Heat Transfer for Staggered Arrays of Impinging Air Jets"
    • San, J. Y., and Lai, M., 2001, "Optimum Jet-to-Jet Spacing of Heat Transfer for Staggered Arrays of Impinging Air Jets," Int. J. Heat Mass Transfer, 44, pp. 3997-4007.
    • (2001) Int. J. Heat Mass Transfer , vol.44 , pp. 3997-4007
    • San, J.Y.1    Lai, M.2
  • 54
    • 0026205705 scopus 로고
    • "Heat Transfer to a Row of Impinging Circular Air Jets Including the Effect of Entrainment"
    • Goldstein, R., and Seol, W. S., 1991, "Heat Transfer to a Row of Impinging Circular Air Jets Including the Effect of Entrainment," Int. J. Heat Mass Transfer, 34, pp. 2133-2147.
    • (1991) Int. J. Heat Mass Transfer , vol.34 , pp. 2133-2147
    • Goldstein, R.1    Seol, W.S.2


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