Drag and lift forces on a rigid sphere immersed in a wall-bounded linear shear flow

Drag and lift forces acting on a spherical water droplet in a homogeneous linear shear air flow were studied by means of a three-dimensional direct numerical simulation based on a marker and cell (MAC) method. The effects of the fluid shear rate and the particle (droplet) Reynolds number on drag and lift forces acting on a spherical droplet were compared with those on a rigid sphere. The results show that the drag coefficient on a spherical droplet in a linear shear flow increases with increasing the fluid shear rate. The difference in the drag coefficient between a spherical droplet and a rigid sphere in a linear shear flow never exceeds 4%. The lift force acting on a spherical droplet changes its sign from a positive to a negative value at a particle Reynolds number of Rep ≃ 50 in a linear shear flow and it acts from the high-speed side to the low-speed side for Rep ≥ 50. The behaviour of the lift coefficient on a spherical droplet is similar to that on a stationary rigid sphere and the change of sign is caused by the decrease of the pressure lift. The viscous lift on a spherical droplet is smaller than that on a rigid sphere at the same Rep, whereas the pressure lift becomes larger. These quantitative differences are caused by the flow inside a spherical droplet.

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Drag and lift forces on a spherical particle moving on a wall in a shear flow at finite Re

Journal of Fluid Mechanics ◽

10.1017/s0022112010001382 ◽

2010 ◽

Vol 657 ◽

pp. 89-125 ◽

Cited By ~ 48

Author(s):

HYUNGOO LEE ◽

S. BALACHANDAR

Keyword(s):

Reynolds Number ◽

Shear Flow ◽

Hydrodynamic Forces ◽

Immersed Boundary ◽

Bounded Linear ◽

Number Range ◽

Linear Shear ◽

Present Composite ◽

Lift Forces ◽

Drag And Lift

Recent research (Zeng, PhD thesis, 2007; Zeng et al., Phys. Fluids, vol. 21, 2009, art. no. 033302) has shown that both the shear- and wall-induced lift contributions on a particle sharply increase as the gap between the wall and the particle is decreased. Explicit expressions that are valid over a range of finite Re were obtained for the drag and lift forces in the limiting cases of a stationary particle in wall-bounded linear flow and of a particle translating parallel to a wall in a quiescent ambient. Here we consider the more general case of a translating and rotating particle in a wall-bounded linear shear flow where shear, translational and rotational effects superpose. We have considered a modest Reynolds number range of 1–100. Direct numerical simulations using immersed boundary method were performed to systematically figure out the characteristics of hydrodynamic forces on a finite-sized particle moving while almost in contact with a wall. We present composite correlation for the hydrodynamic forces which are in agreement with all the available low-Reynolds-number theories.

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Drag and lift forces acting on a spherical bubble in a linear shear flow

International Journal of Multiphase Flow ◽

10.1016/s0301-9322(00)00073-2 ◽

2001 ◽

Vol 27 (7) ◽

pp. 1247-1258 ◽

Cited By ~ 34

Author(s):

R. Kurose ◽

R. Misumi ◽

S. Komori

Keyword(s):

Shear Flow ◽

Spherical Bubble ◽

Linear Shear ◽

Lift Forces ◽

Drag And Lift

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Drag and lift forces on a rotating sphere in a linear shear flow

Journal of Fluid Mechanics ◽

10.1017/s0022112099004164 ◽

1999 ◽

Vol 384 ◽

pp. 183-206 ◽

Cited By ~ 225

Author(s):

RYOICHI KUROSE ◽

SATORU KOMORI

Keyword(s):

Shear Flow ◽

Lift Force ◽

Fluid Velocity ◽

Reynolds Numbers ◽

Fluid Shear ◽

Rotating Sphere ◽

High Particle ◽

Linear Shear ◽

Lift Forces ◽

Drag And Lift

The drag and lift forces acting on a rotating rigid sphere in a homogeneous linear shear flow are numerically studied by means of a three-dimensional numerical simulation. The effects of both the fluid shear and rotational speed of the sphere on the drag and lift forces are estimated for particle Reynolds numbers of 1[les ]Rep[les ]500.The results show that the drag forces both on a stationary sphere in a linear shear flow and on a rotating sphere in a uniform unsheared flow increase with increasing the fluid shear and rotational speed. The lift force on a stationary sphere in a linear shear flow acts from the low-fluid-velocity side to the high-fluid-velocity side for low particle Reynolds numbers of Rep<60, whereas it acts from the high-velocity side to the low-velocity side for high particle Reynolds numbers of Rep>60. The change of the direction of the lift force can be explained well by considering the contributions of pressure and viscous forces to the total lift in terms of flow separation. The predicted direction of the lift force for high particle Reynolds numbers is also examined through a visualization experiment of an iron particle falling in a linear shear flow of a glycerin solution. On the other hand, the lift force on a rotating sphere in a uniform unsheared flow acts in the same direction independent of particle Reynolds numbers. Approximate expressions for the drag and lift coefficients for a rotating sphere in a linear shear flow are proposed over the wide range of 1[les ]Rep[les ]500.

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Drag and lift forces acting on a spherical gas bubble in homogeneous shear liquid flow

Journal of Fluid Mechanics ◽

10.1017/s002211200900651x ◽

2009 ◽

Vol 629 ◽

pp. 173-193 ◽

Cited By ~ 6

Author(s):

KEN-ICHI SUGIOKA ◽

SATORU KOMORI

Keyword(s):

Shear Rate ◽

Shear Flow ◽

Lift Force ◽

Lift Coefficient ◽

Gas Bubble ◽

Fluid Shear ◽

Air Bubble ◽

Linear Shear ◽

Lift Forces ◽

Drag And Lift

Drag and lift forces acting on a spherical gas bubble in a homogeneous linear shear flow were numerically investigated by means of a three-dimensional direct numerical simulation (DNS) based on a marker and cell (MAC) method. The effects of fluid shear rate and particle Reynolds number on drag and lift forces acting on a spherical gas bubble were compared with those on a spherical inviscid bubble. The results show that the drag force acting on a spherical air bubble in a linear shear flow increases with fluid shear rate of ambient flow. The behaviour of the lift force on a spherical air bubble is quite similar to that on a spherical inviscid bubble, but the effects of fluid shear rate on the lift force acting on an air bubble in the linear shear flow become bigger than that acting on an inviscid bubble in the particle Reynolds number region of 1≤Rep≤300. The lift coefficient on a spherical gas bubble approaches the lift coefficient on a spherical water droplet in the linear shear air-flow with increase in the internal gas viscosity.

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The lift on a small sphere in wall-bounded linear shear flows

Journal of Fluid Mechanics ◽

10.1017/s0022112093000114 ◽

1993 ◽

Vol 246 ◽

pp. 249-265 ◽

Cited By ~ 134

Author(s):

John B. McLaughlin

Keyword(s):

Shear Flow ◽

Closed Form ◽

Lift Force ◽

Closed Form Solution ◽

Analytical Form ◽

Form Solution ◽

Rigid Sphere ◽

Small Sphere ◽

Bounded Linear ◽

Linear Shear

This paper presents a closed-form solution for the inertial lift force acting on a small rigid sphere that translates parallel to a flat wall in a linear shear flow. The results provide connections between results derived by other workers for various limiting cases. An analytical form for the lift force is derived in the limit of large separations. Some new results are presented for the disturbance flow created by a small rigid sphere translating through an unbounded linear shear flow.

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