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David R Dowling - One of the best experts on this subject based on the ideXlab platform.
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turbulence profiles from a Smooth Flat Plate turbulent boundary layer at high reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications (Rex ∼ 108–1010), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 (Rex from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished (k+
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Turbulence profiles from a Smooth Flat-Plate turbulent boundary layer at high Reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications ( Re x ∼ 10 8 –10 10 ), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 ( Re x from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished ( k + −1 . The TBL on the model developed in a mild favorable pressure gradient having an acceleration parameter K ∼ 10 −10 . When plotted with the usual inner and outer scalings, the stream-wise velocity variance profiles display a Reynolds number dependence that is consistent with prior lower Reynolds-number zero-pressure-gradient TBL measurements. However, using the same normalizations, the profiles of wall-normal velocity variance and Reynolds shear stress are found to be Reynolds number independent, or nearly so, when experimental uncertainties are considered.
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the mean velocity profile of a Smooth Flat Plate turbulent boundary layer at high reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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The mean velocity profile of a Smooth-Flat-Plate turbulent boundary layer at high Reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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High-Reynolds-number turbulent-boundary-layer wall pressure fluctuations with skin-friction reduction by air injection
The Journal of the Acoustical Society of America, 2008Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, Brian R. Elbing, David R DowlingAbstract:The hydrodynamic pressure fluctuations that occur on the solid surface beneath a turbulent boundary layer are a common source of flow noise. This paper reports multipoint surface pressure fluctuation measurements in water beneath a high-Reynolds-number turbulent boundary layer with wall injection of air to reduce skin-friction drag. The experiments were conducted in the U.S. Navy’s Large Cavitation Channel on a 12.9-m-long, 3.05-m-wide hydrodynamically Smooth Flat Plate at freestream speeds up to 20m∕s and downstream-distance-based Reynolds numbers exceeding 200×106. Air was injected from one of two spanwise slots through flush-mounted porous stainless steel frits (∼40μm mean pore diameter) at volume flow rates from 17.8 to 142.5l∕s per meter span. The two injectors were located 1.32 and 9.78m from the model’s leading edge and spanned the center 87% of the test model. Surface pressure measurements were made with 16 flush-mounted transducers in an “L-shaped” array located 10.7m from the Plate’s leading edg...
Eric S Winkel - One of the best experts on this subject based on the ideXlab platform.
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turbulence profiles from a Smooth Flat Plate turbulent boundary layer at high reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications (Rex ∼ 108–1010), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 (Rex from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished (k+
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Turbulence profiles from a Smooth Flat-Plate turbulent boundary layer at high Reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications ( Re x ∼ 10 8 –10 10 ), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 ( Re x from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished ( k + −1 . The TBL on the model developed in a mild favorable pressure gradient having an acceleration parameter K ∼ 10 −10 . When plotted with the usual inner and outer scalings, the stream-wise velocity variance profiles display a Reynolds number dependence that is consistent with prior lower Reynolds-number zero-pressure-gradient TBL measurements. However, using the same normalizations, the profiles of wall-normal velocity variance and Reynolds shear stress are found to be Reynolds number independent, or nearly so, when experimental uncertainties are considered.
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the mean velocity profile of a Smooth Flat Plate turbulent boundary layer at high reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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The mean velocity profile of a Smooth-Flat-Plate turbulent boundary layer at high Reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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High-Reynolds-number turbulent-boundary-layer wall pressure fluctuations with skin-friction reduction by air injection
The Journal of the Acoustical Society of America, 2008Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, Brian R. Elbing, David R DowlingAbstract:The hydrodynamic pressure fluctuations that occur on the solid surface beneath a turbulent boundary layer are a common source of flow noise. This paper reports multipoint surface pressure fluctuation measurements in water beneath a high-Reynolds-number turbulent boundary layer with wall injection of air to reduce skin-friction drag. The experiments were conducted in the U.S. Navy’s Large Cavitation Channel on a 12.9-m-long, 3.05-m-wide hydrodynamically Smooth Flat Plate at freestream speeds up to 20m∕s and downstream-distance-based Reynolds numbers exceeding 200×106. Air was injected from one of two spanwise slots through flush-mounted porous stainless steel frits (∼40μm mean pore diameter) at volume flow rates from 17.8 to 142.5l∕s per meter span. The two injectors were located 1.32 and 9.78m from the model’s leading edge and spanned the center 87% of the test model. Surface pressure measurements were made with 16 flush-mounted transducers in an “L-shaped” array located 10.7m from the Plate’s leading edg...
Marc Perlin - One of the best experts on this subject based on the ideXlab platform.
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turbulence profiles from a Smooth Flat Plate turbulent boundary layer at high reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications (Rex ∼ 108–1010), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 (Rex from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished (k+
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Turbulence profiles from a Smooth Flat-Plate turbulent boundary layer at high Reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications ( Re x ∼ 10 8 –10 10 ), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 ( Re x from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished ( k + −1 . The TBL on the model developed in a mild favorable pressure gradient having an acceleration parameter K ∼ 10 −10 . When plotted with the usual inner and outer scalings, the stream-wise velocity variance profiles display a Reynolds number dependence that is consistent with prior lower Reynolds-number zero-pressure-gradient TBL measurements. However, using the same normalizations, the profiles of wall-normal velocity variance and Reynolds shear stress are found to be Reynolds number independent, or nearly so, when experimental uncertainties are considered.
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the mean velocity profile of a Smooth Flat Plate turbulent boundary layer at high reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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The mean velocity profile of a Smooth-Flat-Plate turbulent boundary layer at high Reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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High-Reynolds-number turbulent-boundary-layer wall pressure fluctuations with skin-friction reduction by air injection
The Journal of the Acoustical Society of America, 2008Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, Brian R. Elbing, David R DowlingAbstract:The hydrodynamic pressure fluctuations that occur on the solid surface beneath a turbulent boundary layer are a common source of flow noise. This paper reports multipoint surface pressure fluctuation measurements in water beneath a high-Reynolds-number turbulent boundary layer with wall injection of air to reduce skin-friction drag. The experiments were conducted in the U.S. Navy’s Large Cavitation Channel on a 12.9-m-long, 3.05-m-wide hydrodynamically Smooth Flat Plate at freestream speeds up to 20m∕s and downstream-distance-based Reynolds numbers exceeding 200×106. Air was injected from one of two spanwise slots through flush-mounted porous stainless steel frits (∼40μm mean pore diameter) at volume flow rates from 17.8 to 142.5l∕s per meter span. The two injectors were located 1.32 and 9.78m from the model’s leading edge and spanned the center 87% of the test model. Surface pressure measurements were made with 16 flush-mounted transducers in an “L-shaped” array located 10.7m from the Plate’s leading edg...
Steven L Ceccio - One of the best experts on this subject based on the ideXlab platform.
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turbulence profiles from a Smooth Flat Plate turbulent boundary layer at high reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications (Rex ∼ 108–1010), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 (Rex from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished (k+
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Turbulence profiles from a Smooth Flat-Plate turbulent boundary layer at high Reynolds number
Experimental Thermal and Fluid Science, 2012Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, James M Cutbirth, David R DowlingAbstract:Abstract Much is known about Smooth-Flat-Plate turbulent boundary layers (TBLs) at laboratory-scale Reynolds numbers because of a wealth of experimental data. However, Smooth-Flat-Plate TBL data are much less common at the high Reynolds numbers typical of aerodynamic and hydrodynamic applications ( Re x ∼ 10 8 –10 10 ), and at the even higher Reynolds numbers of many geophysical flows. This paper presents new LDV-measured profiles of the stream-wise velocity variance, the wall-normal velocity variance, and the Reynolds shear stress from the TBL that formed on a Smooth Flat Plate at Karman numbers from 15,000 to 60,000 ( Re x from 75 million to 220 million). The experiments were conducted in the William B. Morgan Large Cavitation Channel on a polished ( k + −1 . The TBL on the model developed in a mild favorable pressure gradient having an acceleration parameter K ∼ 10 −10 . When plotted with the usual inner and outer scalings, the stream-wise velocity variance profiles display a Reynolds number dependence that is consistent with prior lower Reynolds-number zero-pressure-gradient TBL measurements. However, using the same normalizations, the profiles of wall-normal velocity variance and Reynolds shear stress are found to be Reynolds number independent, or nearly so, when experimental uncertainties are considered.
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the mean velocity profile of a Smooth Flat Plate turbulent boundary layer at high reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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The mean velocity profile of a Smooth-Flat-Plate turbulent boundary layer at high Reynolds number
Journal of Fluid Mechanics, 2010Co-Authors: Ghanem F Oweis, Eric S Winkel, James M Cutbrith, Steven L Ceccio, Marc Perlin, David R DowlingAbstract:Afzal N, 2001, ACTA MECH, V151, P195, DOI 10.1007-BF01246918; Barenblatt GI, 2000, PHYS FLUIDS, V12, P2159, DOI 10.1063-1.1287613; BENEDICT RP, 1984, FUNDAMENTALS TEMPERA, P340; Bourassa C, 2009, J FLUID MECH, V634, P359, DOI 10.1017-S0022112009007289; Buschmann MH, 2003, AIAA J, V41, P565, DOI 10.2514-2.1994; Compton DA, 1996, EXP FLUIDS, V22, P111, DOI 10.1007-s003480050028; Compton DA, 1997, J FLUID MECH, V350, P189, DOI 10.1017-S0022112097007106; DeGraaff DB, 2000, J FLUID MECH, V422, P319, DOI 10.1017-S0022112000001713; Elbing BR, 2008, J FLUID MECH, V612, P201, DOI 10.1017-S0022112008003029; Etter RJ, 2005, MEAS SCI TECHNOL, V16, P1701, DOI 10.1088-0957-0233-16-9-001; Fernholz HH, 1996, PROG AEROSP SCI, V32, P245, DOI 10.1016-0376-0421(95)00007-0; FERNHOLZ HH, 1995, PHYS FLUIDS, V7, P1275, DOI 10.1063-1.868516; Fife P, 2005, J FLUID MECH, V532, P165, DOI 10.1017-S0022112005003988; Gad-el-Hak M., 1994, APPL MECH REV, V47, P307, DOI DOI 10.1115-1.3111083; George W. K., 1997, APPL MECH REV, V50, P689, DOI [10.1115-1.3101858, DOI 10.1115-1.3101858]; Knobloch K, 2002, IUTAM S REYN NUMB SC, P11; Kunkel GJ, 2006, J FLUID MECH, V548, P375, DOI 10.1017-S0022112005007780; Launder B. E., 1972, MATH MODELS TURBULEN; LINDGREN B, 2004, A H M M H J A V H J, V502, P127; Marusic I, 1997, PHYS FLUIDS, V9, P3718, DOI 10.1063-1.869509; Marusic I, 2010, PHYS FLUIDS, V22, DOI 10.1063-1.3453711; Marusic I, 2003, PHYS FLUIDS, V15, P2461, DOI 10.1063-1.1589014; McKeon BJ, 2007, PHILOS T R SOC A, V365, P635, DOI 10.1098-rsta.2006.1952; Metzger MM, 2001, PHYS FLUIDS, V13, P692, DOI 10.1063-1.1344894; Metzger MM, 2001, PHYS FLUIDS, V13, P1819, DOI 10.1063-1.1368852; Monkewitz PA, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.2972935; Monkewitz PA, 2007, PHYS FLUIDS, V19, DOI 10.1063-1.2780196; Nagib HM, 2008, PHYS FLUIDS, V20, DOI 10.1063-1.3006423; Nagib HM, 2004, IUTAM S 100 YEARS BO, P383; Osterlund JM, 2000, PHYS FLUIDS, V12, P2360, DOI 10.1063-1.1287660; OSTERLUND JM, 2000, A H M H, V12, P1; OSTERLUND JM, 1999, 30 AIAA FLUID DYN C; PANTON RC, 2002, PHYS FLUIDS, V14, P180; Park J. T., 2003, P 4 ASME JSME JOINT; Pope S. B., 2000, TURBULENT FLOWS; SADDOUGHI SG, 1994, J FLUID MECH, V268, P333, DOI 10.1017-S0022112094001370; Sanders WC, 2006, J FLUID MECH, V552, P353, DOI 10.1017-S0022112006008688; SCHULTZGRUNOW F, 1941, 1718 NACA, P1; Sreenivasan K. R., 1989, EXP FLUID, V46, P159; Wei T, 2005, J FLUID MECH, V522, P303, DOI 10.1017-S0022112004001958; White F. M., 2006, VISCOUS FLUID FLOW; Winkel ES, 2009, J FLUID MECH, V621, P259, DOI 10.1017-S0022112008004874
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High-Reynolds-number turbulent-boundary-layer wall pressure fluctuations with skin-friction reduction by air injection
The Journal of the Acoustical Society of America, 2008Co-Authors: Eric S Winkel, Steven L Ceccio, Marc Perlin, Brian R. Elbing, David R DowlingAbstract:The hydrodynamic pressure fluctuations that occur on the solid surface beneath a turbulent boundary layer are a common source of flow noise. This paper reports multipoint surface pressure fluctuation measurements in water beneath a high-Reynolds-number turbulent boundary layer with wall injection of air to reduce skin-friction drag. The experiments were conducted in the U.S. Navy’s Large Cavitation Channel on a 12.9-m-long, 3.05-m-wide hydrodynamically Smooth Flat Plate at freestream speeds up to 20m∕s and downstream-distance-based Reynolds numbers exceeding 200×106. Air was injected from one of two spanwise slots through flush-mounted porous stainless steel frits (∼40μm mean pore diameter) at volume flow rates from 17.8 to 142.5l∕s per meter span. The two injectors were located 1.32 and 9.78m from the model’s leading edge and spanned the center 87% of the test model. Surface pressure measurements were made with 16 flush-mounted transducers in an “L-shaped” array located 10.7m from the Plate’s leading edg...
S V Prabhu - One of the best experts on this subject based on the ideXlab platform.
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Experimental investigation on the local heat transfer with a circular jet impinging on a metal foamed Flat Plate
International Journal of Heat and Mass Transfer, 2020Co-Authors: Ketan Yogi, Mayur Manik Godase, Mikhil Shetty, Shankar Krishnan, S V PrabhuAbstract:Abstract The present study is concerned with an experimental investigation of the local heat transfer coefficient for an air jet impinging on a metal foamed Flat Plate having different pore densities using a thin metal foil technique. The augmentation of heat transfer caused by the metal foams in comparison with heat transfer on a Flat Plate is quantified. The experiments are performed to measure the temperature distribution of the metal foamed Flat Plate with the help of an infrared themal camera. Alunumium metal foams having 8 mm thickness and pore densities of 10, 20 and 40 pores per inch (PPI) are studied. The porosity and thickness of the each aluminum metal foam is 92 %. The range of the Reynolds number (based on the nozzle diameter) covered in the study is 10000 to 25000 and the nozzle to Plate spacing varied from 2 to 10 nozzle diameter. The local Nusselt number is highest at the stagnation region, and it decreases in the radial direction away from the stagnation point. Metal foamed Flat Plate enhances the heat transfer performance compared to a Smooth Flat Plate irrespective of metal foam pore density (pores per inch). The stagnation Nusselt number and average Nusselt number for the metal foamed Flat Plate is consistently higher compared to the Smooth Flat Plate. A metal foamed Flat Plate with a pore density of 10 PPI results in higher augmentation of the stagnation and average Nusselt number compared to metal foamed Flat Plates with a pore density of 20 and 40 PPI. Metal foamed Flat Plate shows little decrement in the stagnation Nusselt number with an increase in the nozzle to Plate spacing irrespective of the pore density. The average Nusselt number seems to be insensitive to the nozzle to Plate spacing. Region wise semi-empirical correlations of the local Nusselt number based on the Reynolds number (Re), non-dimensional radial distance (r/d) and non-diamnesional nozzle to Plate spacing (r/d) are proposed.
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influence of jet temperature and nozzle shape on the heat transfer distribution between a Smooth Plate and impinging air jets
International Journal of Thermal Sciences, 2016Co-Authors: Ravish Vinze, Sunil Chandel, M D Limaye, S V PrabhuAbstract:Abstract Experiments are performed to study the effects of nozzle shape, jet temperature and nozzle to distance (z/de) on heat transfer distribution due to impingement of air jet on a Smooth Flat Plate. Thin metal foil technique is employed in this study for measuring local wall temperature. Influence of jet temperature (70–175 °C) on local heat transfer and effectiveness is studied for different Reynolds numbers (5000–23,000) and jet to Plate distances (1–10) for circular jets. Influence of nozzle shape (circular, square and triangular) on local heat transfer distribution and effectiveness is studied for Reynolds number of 10,000 and 23,000 at different jet to Plate distances. Reynolds number is calculated on the basis of equivalent diameter (10 mm). Nusselt number measured based on equivalent diameter is the highest for a circular nozzle in comparison with square and triangular nozzles. The effect of jet temperature on heat transfer is found marginal and axis switching is observed for non-circular jets. The axis switching for triangular and square nozzles mechanism is governed by ωx dynamics.
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local heat transfer distribution on a Smooth Flat Plate impinged by a slot jet
International Journal of Heat and Mass Transfer, 2011Co-Authors: M Nirmalkumar, Vadiraj Katti, S V PrabhuAbstract:Abstract Experimental investigation of local heat transfer distribution on a Smooth Flat Plate impinged by a normal slot jet is conducted. Present study concentrates on the influence of jet-to-Plate spacing (z/b) and Reynolds number on the fluid flow and heat transfer distribution. A single slot jet with an aspect ratio (l/b) of about 50 is chosen to get the fully developed flow at the nozzle exit. Reynolds number based on slot width is varied from 4200 to 12,000 and jet-to-Plate spacing (z/b) is varied from 0.5 to 12. The local heat transfer coefficients are estimated from the thermal images obtained from infrared thermal imaging camera. Measurement for the static wall pressure is carried out for various jet-to-Plate spacings at a Reynolds number of 12,000. Normalized value of turbulence and velocity are measured using hot wire anemometer along the streamwise direction (x/b) for jet-to-Plate spacings (z/b) of 1, 2, 4, 6, 8, 10 and 12. The entire flow field is divided into three regimes namely stagnation region (laminar boundary layer associated with favorable pressure gradient), transition region (associated with increase in turbulence intensities and heat transfer) and turbulent wall jet region. Semi-empirical correlation for the Nusselt number in the stagnation region is proposed. Heat transfer characteristics in the transition region are explained based on the fluid dynamic behavior from the hot wire measurements. Semi-empirical correlation for the Nusselt number in the wall jet region is presented using the velocity profile obtained from the hot wire measurements.
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Local heat transfer distribution on a Smooth Flat Plate impinged by a slot jet
International Journal of Heat and Mass Transfer, 2011Co-Authors: M Nirmalkumar, Vadiraj Katti, S V PrabhuAbstract:Experimental investigation of local heat transfer distribution on a Smooth Flat Plate impinged by a normal slot jet is conducted. Present study concentrates on the influence of jet-to-Plate spacing (z/b) and Reynolds number on the fluid flow and heat transfer distribution. A single slot jet with an aspect ratio (l/b) of about 50 is chosen to get the fully developed flow at the nozzle exit. Reynolds number based on slot width is varied from 4200 to 12,000 and jet-to-Plate spacing (z/b) is varied from 0.5 to 12. The local heat transfer coefficients are estimated from the thermal images obtained from infrared thermal imaging camera. Measurement for the static wall pressure is carried out for various jet-to-Plate spacings at a Reynolds number of 12,000. Normalized value of turbulence and velocity are measured using hot wire anemometer along the streamwise direction (x/b) for jet-to-Plate spacings (z/b) of 1, 2, 4, 6, 8, 10 and 12. The entire flow field is divided into three regimes namely stagnation region (laminar boundary layer associated with favorable pressure gradient), transition region (associated with increase in turbulence intensities and heat transfer) and turbulent wall jet region. Semi-empirical correlation for the Nusselt number in the stagnation region is proposed. Heat transfer characteristics in the transition region are explained based on the fluid dynamic behavior from the hot wire measurements. Semi-empirical correlation for the Nusselt number in the wall jet region is presented using the velocity profile obtained from the hot wire measurements. (C) 2010 Elsevier Ltd. All rights reserved