Numerical analysis of lamination effect in a vortex micro T-mixer with non-aligned inputs

Rabani, Ramin; Talebi, Shahriar; Rabani, Mehrdad

doi:10.1007/s00231-015-1584-5

Cited by 15 publications

(5 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This region can be identified as a stratified flow regime instead of a segregated flow regime due to the nonexistence of a certain segregation of the fluid streams. Unlike the liquid mixing in nonaligned T-jet reactors, 31,34 vortex flow emerges at Re = 70. At 70 ≤ Re ≤ 230, the vortex flow of the fluid streams can be easily observed (the animation in Supporting Information Video 5).…”

Section: Piv Setup and Measurementsmentioning

confidence: 94%

“…The effect of stratification was found to be decreased in the engulfment regime since the convection overruled the diffusion . Recently, in addition to these conventional mixer geometries, liquid mixing in T-mixers with nonaligned inputs has been studied. − It was found that vortex flow is formed at Re > 40 in these nonaligned reactors. Similarly, the flow regime is divided into three regions including segregated flow, steady engulfment flow (40 < Re < 215), and unsteady engulfment flow ( Re > 215) …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Gas Flow Hydrodynamics in Vortex Mixers: Flow Visualization and PIV Flow Field Characterization

Gecim

Erkoç

2021

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The gas flow hydrodynamics in a vortex mixer was investigated using flow visualization and particle image velocimetry (PIV) techniques for several Reynolds numbers ranging from Re = 20 to 280 and equal momentum of the jets. The flow regime transition of two methane gas streams coming from two tangential jets was analyzed by the detection of the critical Reynolds number of the flow. This critical point was determined from time-averaged and instantaneous flow images, velocity fluctuations, and hence turbulence intensity values of the vortex mixer. Results show that the flow gained the swirl motion at Re = 70 and the instabilities in the flow started at around Re = 230, where the gas flow hydrodynamics was diffusion controlled. Beyond Re = 230, the flow was unsteady and chaotic flow overruled the molecular diffusion and the ensemble mixing of the gases dependent on the convection was achieved starting from this point. This study sheds light on the gas flow hydrodynamics of a vortex mixer and points out the flow regime transitions.

show abstract

Section: Piv Setup and Measurementsmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 99%

Gas Flow Hydrodynamics in Vortex Mixers: Flow Visualization and PIV Flow Field Characterization

Gecim

Erkoç

2021

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…Usually these mixers are characterized by the jets tangential to the main mixing chamber, which can be prismatic or cylindrical. While prismatic chambers were studied only for liquids as microreactors, − cylindrical chambers in small diameters (with a jet diameter of 1mm and a chamber diameter of 2–4 mm) were used to manufacture nanoparticles using liquid precursors. , …”

Section: Introductionmentioning

confidence: 99%

Hydrodynamics of Similar Gases in Vortex Mixers: Effect of Physical Properties on the Onset of Instability

Gecim

Erkoç

2022

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The effect of physical properties of gases on the flow hydrodynamics and on the onset of instability was studied to acquire information on how to design fast mixers specific for relevant operations where complete and improved gas mixing is important. To assess the effect of physical properties on the gas flow dynamics in vortex mixers, three gases hydrogen, nitrogen, and argon were chosen because of the viscosity and density differences they provide. Using flow visualization and PIV flow-field characterization techniques, critical Reynolds numbers of flow regime changes were identified from segregated to engulfment flow regimes for three pairs of gases. It was shown that the first critical point of the flow, where the gases have a full rotation in the chamber, depends on the inertial force in terms of dynamic pressure. While hydrogen having the highest kinematic viscosity had a full rotation at Re = 40, nitrogen and argon gases had their full rotation at Re = 70. After these points, a steady rotational flow as a consequence of the balance between the centrifugal and centripetal forces was observed. Similarly, the onset of the engulfment regime was observed earlier for hydrogen, at Re = 150, while it was at Re = 200 for nitrogen and Re = 220 for argon. The present study shows that the gas properties are effective parameters not only on the critical points but also on the shape of the swirling flow pattern formed in the mixer.

show abstract

“…Rabani et al 30 studied how mixing performance improved by geometry lamination at the inlet of the micromixer. It has been concluded that lamination increases the interface of the fluids which creates more fluid flow rotations.…”

Section: Introductionmentioning

confidence: 99%

Numerical analysis of non-aligned inputs M-type micromixers with different shaped obstacles for biomedical applications

Irfan

Shah

Niazi³

et al. 2021

Proceedings of the Institution of Mechanical Engineers, Part E:

View full text Add to dashboard Cite

Fluid mixing in lab-on-a-chip devices at laminar flow conditions result in a low mixing index. The reason is dominant diffusion over the convection process. The mixing index can be improved by certain changes in the micromixer structural design like introducing obstacles in the path of fluid flow. These obstacles will make dominant the advection process over the diffusion process. The main contribution of this work is based on proposing the novel hybrid type micromixer design for enhancing the mixing quality. Three non-aligned M-type and non-aligned M-type with obstacles passive type micromixers are analyzed by COMSOL5.5. These designs are hybrid types because different structural changes are combined in a single design for mixing improvement. First of all the straight non-aligned inlets, M-type passive micromixer (SMTM) is analyzed. It is observed that mixing performance is improved because of M-shaped mixing units and non-aligned inlets. This improvement is deemed to be not enough so different shaped obstacles are introduced in the micromixer design. These designs based on obstacles are named horizontal rectangular M-type micromixer, square M-type micromixer, and vertical rectangular M-type micromixer. The mixing index for SMTM, square M-type micromixer, horizontal rectangular M-type micromixer, and vertical rectangular M-type micromixer at Reynolds number Re = 60 is respectively given by 71.1%, 83.21%, 84.45%, and 89.99%. The mixing index of vertical rectangular M-type micromixer was 59.34% − 87.65% for Re = 0.5–100. Vertical rectangular M-type micromixer is concluded with the better-mixing capability design among the proposed ones. Based on these simulation results, the vertical rectangular M-type micromixer design can be utilized for mixing purposes in biomedical applications like nanoparticle synthesis and biomedical sample preparation for drug delivery.

show abstract

Numerical analysis of lamination effect in a vortex micro T-mixer with non-aligned inputs

Cited by 15 publications

References 22 publications

Gas Flow Hydrodynamics in Vortex Mixers: Flow Visualization and PIV Flow Field Characterization

Gas Flow Hydrodynamics in Vortex Mixers: Flow Visualization and PIV Flow Field Characterization

Hydrodynamics of Similar Gases in Vortex Mixers: Effect of Physical Properties on the Onset of Instability

Numerical analysis of non-aligned inputs M-type micromixers with different shaped obstacles for biomedical applications

Contact Info

Product

Resources

About