Taylor-Dean Flow Research Articles

Transient Taylor—Dean flow in a composite annulus partially filled with porous material

Transient Taylor—Dean flow in a composite annulus partially filled with porous material

On the transition of transient growth mechanism in Taylor–Dean flow

We investigate optimal perturbation and its transient growth characteristics in Taylor–Dean flow theoretically. The parameter [Formula: see text], accounting for the ratio of average pumping velocity induced by azimuthal pressure gradient to rotating velocity by rotating cylinders, is varied from −5 to 5. The results show that for the rigid rotation case, the energy growth of optimal perturbation is increased with increasing magnitude of azimuthal pressure gradient. Further, both the main and secondary peak of the amplitude of azimuthal velocity are seen to be shifted towards the outer cylinder for wide gap case, and both are shifted oppositely towards the inner cylinder for narrow gap case. Viewing the time evolution of the energies in the three velocity components for wide gap case, anti-lift-up mechanism replaces lift-up mechanism as the dominant mechanism for energy growth, when [Formula: see text] changes from −5 to 5. While for narrow gap case, lift-up mechanism is always responsible for transient growth of axisymmetric perturbation, no matter how strong azimuthal pressure gradient is considered.

Experimental and Numerical Study of the Micromixer Using the Taylor-Dean Flow

Experimental and Numerical Study of the Micromixer Using the Taylor-Dean Flow

Experimental and Numerical Study of the Micromixer Using the Taylor-Dean Flow

Experimental and Numerical Study of the Micromixer Using the Taylor-Dean Flow

Experimental and Numerical Study of the Micromixer Using the Taylor-Dean Flow

Experimental and Numerical Study of the Micromixer Using the Taylor-Dean Flow

A Micromixer Using the Taylor-Dean Flow: Rotation Effect of Channel Walls on the Mixing

A Micromixer Using the Taylor-Dean Flow: Rotation Effect of Channel Walls on the Mixing

テイラー・ディーン流れを利用したマイクロミキサの研究

テイラー・ディーン流れを利用したマイクロミキサの研究

1308 テイラー・ディーン流れを利用したマイクロミキサの実験的研究 : 混合過程に及ぼす二次流れの影響(流体工学V)

1308 テイラー・ディーン流れを利用したマイクロミキサの実験的研究 : 混合過程に及ぼす二次流れの影響(流体工学V)

1214 テイラー・ディーン流れを利用したマイクロミキサの粒子法解析 : 混合に及ぼす流路の回転効果(流体工学III)

1214 テイラー・ディーン流れを利用したマイクロミキサの粒子法解析 : 混合に及ぼす流路の回転効果(流体工学III)

テイラー・ディーン流れを利用したマイクロミキサの研究

Chaotic mixing in three different types of curved-square channel flow has been studied experimentally and numerically. The wall of channel rotates around the center of curvature and a pressure gradient is imposed in the direction toward the exit of the channel. This flow is a kind of Taylor-Dean flow. Effects of three different types of moving walls, top and inner walls (B.C.1; Boundary Condition 1), an inner wall (B.C.2; Boundary Condition 2), and a top wall (B.C.3; Boundary Condition 3) on chaotic mixing, have been investigated experimentally and numerically. The secondary flow is measured using PIV (Particle Image Velocimetry) and LIF (Laser Induced Fluorescence) methods to examine secondary flow characteristics. Also we performed three-dimensional numerical simulations for the exactly same configuration as the experimental system to study the mechanism of chaotic mixing. It is found that good mixing performance is obtained in the case of B.C.1.

A Micromixer Using the Taylor-Dean Flow: Effects of Aspect Ratio and Inflow Condition on the Mixing

Chaotic mixing in three different types of curved-rectangular channels flow has been studied experimentally and numerically. Two walls of the channel (inner and top walls) rotate around the center of curvature and a pressure gradient are imposed in the direction toward the exit of the channel. This flow is a kind of Taylor-Dean flow. There are two parameters dominating the flow, the Dean number De (∝ the pressure gradient or the Reynolds number) and the Taylor number Tr (∝ the angular velocity of the wall rotation). In this paper, we analyze the physical mechanism of chaotic mixing in the Taylor-Dean flow by comparing experimental results and numerical ones. We produced three micromixer models of the curved channel, several centimeters long, with rectangular cross-section of a few millimeters side. The secondary flow is measured using laser induced fluorescence (LIF) method to examine secondary flow characteristics. Also we performed three-dimensional numerical simulations with the open source CFD solver, OpenFOAM, for the same configuration as the experimental system to study the mechanism of chaotic mixing. It is found that good mixing performance is obtained in the case of De ≤ 0.1 Tr, and it becomes more remarkable when the aspect ratio tends to large. And it is found that the mixing efficiency changes according to the aspect ratio and inflow condition.

GS52 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 流路のアスペクト比の効果

Chaotic mixing in a curved-rectangular channel flow is studied numerically. One wall of the channel (inner wall) rotate around the center of curvature and a pressure gradient is imposed in the direction toward the exit of the channel. This flow is a kind of Taylor-Dean flow. There are two parameters dominating the flow, the Dean number De (∝ the pressure gradient) and the Taylor number Tr (∝ the angular velocity of the wall rotation). In the present paper, we analyze the physical mechanism of chaotic mixing in the Taylor-Dean flow by comparing fluid mixing and velocity field. It is found that good mixing performance is obtained in the case of De/Tr ≤ 1/6. This tendency appears more strongly if aspect ratio is large.

GS51 テイラー・ディーン流れを利用したマイクロミキサの実験的研究 : 混合に及ぼす二次流れの影響

GS51 テイラー・ディーン流れを利用したマイクロミキサの実験的研究 : 混合に及ぼす二次流れの影響

1308 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼす流路の回転効果(流体工学VI)

1308 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼす流路の回転効果(流体工学VI)

A Micromixer Using the Taylor-Dean Flow: Effect of Inflow Conditions on the Mixing

Chaotic mixing in a curved-square channel flow is studied experimentally and numerically. Two walls of the channel (inner and top walls) rotate around the center of curvature and a pressure gradient is imposed in the direction toward the exit of the channel. This flow is a kind of Taylor-Dean flows. There are two parameters dominating the flow, the Dean number De (∝ the pressure gradient or the Reynolds number) and the Taylor number Tr (∝ the angular velocity of the wall rotation). In the present paper, we analyze the physical mechanism of chaotic mixing in the Taylor-Dean flow by comparing experimental and numerical results. We produced a micromixer model of the curved channel several centimeters long with square cross section of a few millimeters side. The secondary flow was measured using laser induced fluorescence (LIF) method to examine secondary flow characteristics. We also performed three-dimensional numerical simulations for the exactly same configuration as the experimental system to study the mechanism of chaotic mixing. It is found that good mixing performance is achieved for the case of De ≤ 0.1Tr, and that mixing efficiency changes according to the difference in inflow conditions. The flow is studied both experimentally and numerically, and both results agree with each other very well.

919 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼす初期条件の影響

919 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼす初期条件の影響

GS14 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼすアスペクト比と流入条件の影響

GS14 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼすアスペクト比と流入条件の影響

S0530103 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼすアスペクト比の影響([S053]内部流れ)

S0530103 テイラー・ディーン流れを利用したマイクロミキサの数値的研究 : 混合に及ぼすアスペクト比の影響([S053]内部流れ)

GS09 テイラー・ディーン流れを利用したマイクロミキサの実験的研究 : 混合過程に及ぼすアスペクト比の効果

The micromixer, which has a rotor with a curved channel, is studied experimentally. The Taylor-Dean flow in a curved channel of rectangular cross-section is investigated using PIV (Particle Image Velocimetry) and LIF (Laser Induced Fluorescence) methods. Two walls of the channel (the inner and top walls) rotate around the center of curvature and a pressure gradient is imposed in the direction of the exit of the channel. The non-dimensional parameters concerned are the Dean number De and the Taylor number Tr. Photographs of the flow in a cross-section at 180° downstream from the curved channel entrance are taken by changing the flux (De) at a constant rotational speed (Tr) of the channel walls. It is found that good mixing performance is obtained in the case of De ≤ 0.1Tr. This tendency appears more strongly if aspect ratio is large. And we have confirmed the effect of aspect ratio on the mixing process.

918 テイラー・ディーン流れを利用したマイクロミキサの実験的研究 : 混合に及ぼすアスペクト比の効果

918 テイラー・ディーン流れを利用したマイクロミキサの実験的研究 : 混合に及ぼすアスペクト比の効果