V06_Chemometrics and Intelligent Laboratory Systems: Passive Diffusive Micromixers

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What is the formula for the time of residence (tr) of a particle in a channel for diffusive mixing?

tr = lchannel / vmean (correct)

tr = lchannel * vmean

tr = lchannel^2 / vmean

tr = vmean / lchannel

In the context of passive diffusive micromixers, what does the diffusion time (tD) represent?

Time taken for particles to accelerate in the channel

Time taken for particles to mix perfectly

Time taken for particles to reach the end of the channel

Time taken for particles to diffuse across the channel width (correct)

What is the minimum channel length required for complete diffusive mixing in a microfluidic system?

lchannel = D / vmean^2

lchannel = tD / vmean

lchannel = vmean / tD

lchannel = vmean^2 / D (correct)

In a Y-mixer design, what is the role of laminar flow in achieving mixing?

Laminar flow helps in maintaining particle velocity Signup and view all the answers

Which parameter determines the minimum channel length for complete mixing in a passive diffusive micromixer?

Diffusion coefficient (D) Signup and view all the answers

How can the channel length be shortened in microfluidic systems?

By incorporating layering techniques Signup and view all the answers

What happens when the diffusivity D is too small in the context of microfluidic systems?

The channel length becomes longer Signup and view all the answers

Which technique is used for passive mixing by interdigitated lamella in microfluidic systems?

Layering technique Signup and view all the answers

How is the minimum channel length reduced by layering techniques in microfluidic systems?

By stacking channels on top of each other Signup and view all the answers

In the context of microfluidic systems, what effect does reducing diffusion length have on the channel design?

Reduces the minimum channel length Signup and view all the answers

What is the main purpose of passive diffusive micromixers in microfluidic systems?

To achieve complete diffusive mixing Signup and view all the answers

What is the primary advantage of using diffusive mixing in microfluidic systems?

It allows for rapid mixing of fluids without the need for active components or external energy sources. Signup and view all the answers

In a Y-mixer configuration, what determines the extent of diffusive mixing between the two inlet fluid streams?

The channel geometry and dimensions after the junction. Signup and view all the answers

What is the relationship between the diffusion length ($l_D$) and the time required for complete diffusive mixing ($t_D$) in a microfluidic channel?

$t_D = l_D^2 / D$ Signup and view all the answers

In a microfluidic channel with laminar flow, what is the diffusion length ($l_D$) typically defined as?

Half of the channel width. Signup and view all the answers

Which of the following statements regarding passive diffusive micromixers is correct?

They rely solely on the channel geometry and diffusion to promote mixing. Signup and view all the answers

What is the primary limitation of passive diffusive micromixers compared to active micromixers?

They require longer channel lengths to achieve complete mixing. Signup and view all the answers