TY - JOUR

T1 - Buoyancy induced secondary vortices in the entrance section of a horizontal straight tube

AU - Sillekens, J.J.M.

AU - Rindt, C.C.M.

AU - Steenhoven, van, A.A.

PY - 1998

Y1 - 1998

N2 - Developing mixed convective flow in the entrance section of a horizontal straight tube is analyzed with special emphasis on the buoyancy-induced secondary vortices. The flow is subject to a constant wall temperature. Elliptic calculations on a half gross-section grid are performed for various Grashof numbers and two Prandtl numbers. It appears that for air (Pr=0.7) the flow exhibits a two-vortex solution for all Grashof numbers and axial positions investigated, whereas for water (Pr=5.0), secondary flow evolves from a two-vortex solution, via a four-voltex solution toward a six-voltex solution for increasing Grashof numbers and axial distances. Calculations on a full cross-section grid reveal that these solutions are axial distances. Calculations on a full cross-section grid reveal that these solutions are insensitive to white noise perturbations in the "initial" flow field.

AB - Developing mixed convective flow in the entrance section of a horizontal straight tube is analyzed with special emphasis on the buoyancy-induced secondary vortices. The flow is subject to a constant wall temperature. Elliptic calculations on a half gross-section grid are performed for various Grashof numbers and two Prandtl numbers. It appears that for air (Pr=0.7) the flow exhibits a two-vortex solution for all Grashof numbers and axial positions investigated, whereas for water (Pr=5.0), secondary flow evolves from a two-vortex solution, via a four-voltex solution toward a six-voltex solution for increasing Grashof numbers and axial distances. Calculations on a full cross-section grid reveal that these solutions are axial distances. Calculations on a full cross-section grid reveal that these solutions are insensitive to white noise perturbations in the "initial" flow field.

U2 - 10.1080/10407789808913943

DO - 10.1080/10407789808913943

M3 - Article

VL - 33

SP - 355

EP - 369

JO - Numerical Heat Transfer. Part A : Applications

JF - Numerical Heat Transfer. Part A : Applications

SN - 1040-7782

IS - 4

ER -