Fluid circuit components based upon passive fluid dynamics

A method of mixing a first fluid and a second fluid within a non-wetted fluid circuit, said method comprising the steps of

• a) inserting said first fluid into a main microchannel of said fluid circuit, wherein said first fluid is forced to flow into a first microchannel of a known volume of said circuit as a result of a first passive stopping means within said main microchannel and wherein said first microchannel comprises a second passive stopping means that creates a pressure barrier stronger than said first passive stopping means, wherein said first fluid is of an amount substantially equal to the volume of said first microchannel, and
• b) inserting said second fluid into said main microchannel of said fluid circuit, wherein said second fluid is forced past said first passive stopping means into a second microchannel, and said first microchannel and said second microchannel converge at said second passive stopping means at which point said first fluid and said second fluid will mix upon continued insertion of said second fluid or application of a force causing said first and second fluids to move.

A method of distributing fluid from one channel to multiple wells, chambers or channels of a non-wetted fluid circuit wherein said method comprises the steps of:

• passing said fluid from said one channel to branching channels leading to a first set of wells, chambers or channels, wherein said first set of wells, chambers or channels comprise a first passive stopping means within each well, chamber or channel thereby causing all wells, chambers or channels upstream of said first passive stopping means to fill prior to said fluid moving to a second set of wells, chambers or channels comprising a second passive stopping means within each well, chamber or channel, wherein the second passive stopping means create a pressure barrier stronger than the first passive stopping means;
• and
• causing fluid to push past the first passive stopping means within the first set of wells, chambers or channels and to stop at the second passive stopping means within the second set of wells, chambers or channels.

A method for consolidating fluids from multiple wells into a common consolidation well, chamber or channel wherein said method comprises:

• a) inserting said fluids into microchannels of a fluid circuit;
• then
• b) forcing said fluids through said microchannels and into wells of said fluid circuit by addition of a second fluid into said microchannels wherein said second fluid is more viscous than said fluids, and wherein said wells exit into channels which are narrower than said wells, and further wherein said exit channels connect to said common consolidation well, chamber or channel, wherein sufficient second fluid is added to force said fluids into said common consolidation well, chamber or channel.

A method of controlling fluid flow through a non-wetted fluid circuit comprising at least two connected microchannels, each said microchannel containing a passive flow barrier that creates a fluid pressure barrier, said method comprising:

• stopping advancing fluid in a first microchannel with a first passive flow barrier, thereby directing fluid into a connected neighboring second microchannel;
• and
• overcoming the pressure barrier of the first passive flow barrier by the advancing fluid engaging a second passive flow barrier in the second microchannel, wherein said second passive flow barrier creates a stronger pressure barrier than the first passive flow barrier.

A method to overcome a capillary stopping means in a non-wetted microchannel comprising the steps:

• stopping advancing fluid flow in a fluid circuit with a capillary stopping means that creates a pressure barrier due to capillary forces dependent upon the presence of a gas-fluid interface, wherein said capillary stopping means has an upstream side and a downstream side in the fluid circuit, and wherein the gas-fluid interface is disposed between the upstream and downstream sides of the capillary stopping means;
• and
• overcoming the pressure barrier by introducing a fluid to the downstream side of the capillary stopping means that wets the downstream side of the capillary stopping means to eliminate the gas-fluid interface at the capillary stopping means.

A non-wetted fluid circuit comprising a plurality of connected microchannels, wherein passive stopping means exist within one or more of said microchannels causing fluid that is advancing through said fluid circuit to flow in an adjoining microchannel connected upstream of said passive stopping means rather than to flow past said stopping means, wherein said fluid circuit further comprises a channel with a chamber wherein said chamber comprises secondary channels.

A non-wetted fluid circuit comprising a first microchannel and a second microchannel wherein said second microchannel branches from said first microchannel upstream of a first passive stopping means within said first microchannel and rejoins said first microchannel downstream of a second passive stopping means within said first microchannel, further wherein said second passive stopping means creates a greater pressure barrier than said first passive stopping means, said fluid circuit further comprising a vent between said first passive stopping means and said second passive stopping means.

A non-wetted fluid circuit comprising a plurality of connected microchannels, wherein passive stopping means exist within one or more of said microchannels, causing fluid that is advancing through said fluid circuit to flow in an adjoining microchannel connected upstream of said passive stopping means rather than to flow past said passive stopping means, wherein at least one of said microchannels branches at a first point into an adjoining microchannel which rejoins said one of said microchannels at a second point and wherein said adjoining microchannel comprises a second passive stopping means immediately upstream of said second point.

A non-wetted fluid circuit comprising a plurality of connected microchannels, wherein a short microchannel narrowing exists within one or more of said microchannels, said microchannel narrowing having an inlet and an outlet, said narrowing having a cross-sectional configuration relative to the inicrochannel that creates a passive pressure barrier causing fluid which is advancing though said fluid circuit preferably to flow in an adjoining microchannel connected upstream of said narrowing rather than to flow past said narrowing.

The fluid circuit of 1 wherein the narrowing is sufficiently short to produce little or no pressure drop across the narrowing in established flow conditions.