Microfluidic Channel Solid Handling via Acoustic Streaming

Solution Overview

Problem

Microfluidic systems face challenges with solid accumulation leading to channel blockages, which disrupts continuous operation and hampers the handling of solids in chemical synthesis and analysis processes.

Innovation Solution

The application of auxiliary acoustic energy and the use of coating materials within microfluidic channels to inhibit solid accumulation, combined with controlled solvent addition and channel geometry design, prevents solid agglomeration and ensures continuous operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If solids are processed in microfluidic channels, then chemical synthesis and analysis can be performed with enhanced heat and mass transfer, but solid accumulation leads to channel blockages

Engineering Contradiction:

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies ultrasonic vibration to the microfluidic channel to prevent solid accumulation and channel blockage. The ultrasonic energy creates acoustic streaming and cavitation effects that keep solid particles suspended and prevent them from adhering to channel walls, thereby maintaining channel functionality while enabling solid processing in microfluidic systems

Inventive Principle:

Principle #18Mechanical vibration

Solution Approach 2:

The patent modifies physical parameters including temperature, pressure, and fluid flow rate to control solid particle behavior. By adjusting these parameters, the system maintains solids in a manageable state that prevents accumulation while enabling continuous processing, thus resolving the contradiction between productivity and reliability

Inventive Principle:

Principle #35Parameter changes

2Reliability

If auxiliary acoustic energy is applied to inhibit solid accumulation, then channel blockage is prevented, but energy consumption increases

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent employs periodic or pulsed ultrasonic activation rather than continuous operation. The acoustic energy is applied in cycles or at specific intervals sufficient to prevent solid accumulation, reducing overall energy consumption while maintaining channel functionality throughout the processing period

Inventive Principle:

Principle #19Periodic action

3Reliability

If coating materials are deposited on channel walls to prevent solid accumulation, then channel blockage is inhibited, but device complexity increases

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent utilizes the flowing fluid itself to deliver and deposit coating materials onto channel walls. The coating precursor is dissolved or suspended in the fluid stream, and the continuous flow automatically distributes and deposits the coating material during normal operation, eliminating the need for separate coating application equipment

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent employs porous coating materials that can be delivered as suspensions or emulsions in the fluid stream. These porous materials provide effective solid particle prevention while being deliverable through simple fluid flow, minimizing additional device complexity

Inventive Principle:

Principle #31Porous materials

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach effectively prevents solid accumulation, allowing for continuous handling of solids without interruptions, maintaining channel functionality and enabling high-throughput processing with controlled conditions for solid formation.

Implementation Method 1

applying auxiliary acoustic energy to the microfluidic channel at a frequency and level of energy selected to inhibit accumulation of the solid in the microfluidic channel

Methodology Applied

Scientific EffectAcoustic radiation pressure: Acoustic Radiation Pressure

Implementation Method 2

applying auxiliary acoustic energy to the microfluidic channel... the pressure drop along the length of the microfluidic channel in the presence of the auxiliary acoustic energy is less than the pressure drop that would be observed in the absence of the auxiliary acoustic energy

Methodology Applied

Scientific EffectAcoustic streaming:

Implementation Method 3

flowing a first fluid containing a first solvent in which the solid is soluble into the microfluidic channel at a first feed inlet, and flowing a second fluid containing a second solvent in which the solid is soluble into the microfluidic channel at a second feed inlet downstream of the first feed inlet

Methodology Applied

Scientific EffectSolvation: Solvation

Implementation Method 4

depositing at least a portion of the coating material precursor on at least a portion of a wall of the microfluidic channel

Methodology Applied

Scientific EffectPhysical deposition: Deposition (physical)

Data Source

PatentUS8763623B2Methods for handling solids in microfluidic systems

Publication Date: 2014.07.01

AI summary

Systems and methods related to handling solids in microfluidic systems are generally described. Many of the systems and methods described herein address the need to inhibit the formation of blockages in microfluidic channels.