TY - GEN
T1 - Characteristics of pressure distribution and skin friction within the laminar separation bubble at different Reynolds numbers
AU - Lee, Donghwi
AU - Kawai, Soshi
AU - Nonomura, Taku
AU - Oyama, Akira
AU - Fujii, Kozo
PY - 2015/1/1
Y1 - 2015/1/1
N2 -
Mechanisms behind the pressure distribution within a laminar separation bubble (LSB) are investigated by largeeddy simulations around a 5% thickness blunt flat plate. The plate length based Reynolds numbers are set to be (Re
c
) 5.0 × 10
3
, 6.1 × 10
3
, 8.0 × 10
4
, 1.1 × 10
4
, and 2.0 × 10
4
. From the results, two types of LSB are observed; steady laminar separation bubble (LSB-S) at Re
c
= 5.0 × 10
3
and 6.1 × 10
3
, and a steady-fluctuating laminar separation bubble (LSB-SF) at Re
c
= 8.0 × 10
3
, 1.1 × 10
4
, and 2.0 × 10
4
. As the Reynolds number increases, different shapes of pressure disribution appear such that a gradual pressure recovery in the LSB-S and a plateau pressure distribution followed by a rapid pressure recovery in the LSB-SF. The reasons of appearing the different shapes of pressure distributions depending on the Reynolds number are explained by deriving the Reynolds averaged pressure gradient equation. From the momentum budgets of the equation, it is confirmed that the viscous stress near the surface has an influence on determining the different shape of pressure distribution. The different viscous stress distributions near the surface are affected by grwoth of the separated laminar shear layer depending on the Reynolds number or generation of the Reynolds shear stress.
AB -
Mechanisms behind the pressure distribution within a laminar separation bubble (LSB) are investigated by largeeddy simulations around a 5% thickness blunt flat plate. The plate length based Reynolds numbers are set to be (Re
c
) 5.0 × 10
3
, 6.1 × 10
3
, 8.0 × 10
4
, 1.1 × 10
4
, and 2.0 × 10
4
. From the results, two types of LSB are observed; steady laminar separation bubble (LSB-S) at Re
c
= 5.0 × 10
3
and 6.1 × 10
3
, and a steady-fluctuating laminar separation bubble (LSB-SF) at Re
c
= 8.0 × 10
3
, 1.1 × 10
4
, and 2.0 × 10
4
. As the Reynolds number increases, different shapes of pressure disribution appear such that a gradual pressure recovery in the LSB-S and a plateau pressure distribution followed by a rapid pressure recovery in the LSB-SF. The reasons of appearing the different shapes of pressure distributions depending on the Reynolds number are explained by deriving the Reynolds averaged pressure gradient equation. From the momentum budgets of the equation, it is confirmed that the viscous stress near the surface has an influence on determining the different shape of pressure distribution. The different viscous stress distributions near the surface are affected by grwoth of the separated laminar shear layer depending on the Reynolds number or generation of the Reynolds shear stress.
UR - http://www.scopus.com/inward/record.url?scp=85034450013&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85034450013&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:85034450013
T3 - 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015
BT - 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015
PB - TSFP-9
T2 - 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015
Y2 - 30 June 2015 through 3 July 2015
ER -