Acoustic acceleration of fluid mixing in porous materials

Abstract

Apparatus and methods are disclosed for uniformly mixing fluid phases entrained in a porous material.

1 . A porous material mixer comprising:
 a vessel for holding at least one porous material;   at least one actuator acoustically coupled with at least one wall of said vessel for generating a wave; and   at least one inlet in said vessel for admitting at least two fluids for combining, wherein said wave effects mixing of said at least two fluids.   
   
   
       2 . The mixer according to  claim 1  further comprising a linear motor coupled to said actuator wherein, when excited by a control signal, said motor exhibits an excursion. 
   
   
       3 . The mixer according to  claim 2  wherein said excursion applies a force against said actuator. 
   
   
       4 . The mixer according to  claim 3  wherein said excursion and said actuator acoustic coupling shapes said wave. 
   
   
       5 . The mixer according to  claim 4  wherein said actuator acoustic coupling is provided by at least two points separated by a predefined distance. 
   
   
       6 . The mixer according to  claim 5  wherein said force is coupled through said vessel wall into said at least one porous material. 
   
   
       7 . The mixer according to  claim 6  wherein said actuator alternately applies force to each said point. 
   
   
       8 . The mixer according to  claim 7  wherein said linear motor is a piezoelectric transducer. 
   
   
       9 . The mixer according to  claim 8  wherein said excitation control signal alternates at a frequency in a range of from about 1 to 20 MHz. 
   
   
       10 . The mixer according to  claim 9  wherein a difference between alternate force applications corresponds to about 180 degrees. 
   
   
       11 . The mixer according to  claim 10  wherein said wave within said at least one porous material is a compression/expansion wave that corresponds with said alternate force applications. 
   
   
       12 . The mixer according to  claim 11  wherein said at least one porous material is one mono-layer. 
   
   
       13 . The mixer according to  claim 11  wherein said at least one porous material is a sandwich of more than one type of porous material. 
   
   
       14 . A method for mixing at least two fluids in a porous material comprising:
 introducing the fluids into a mixing vessel, said mixing vessel comprising:
 at least one inlet; 
 at least one linear motor coupled to at least one actuator wherein said actuator is acoustically coupled to a wall of said vessel; 
   exciting said at least one linear motor with a control signal of predetermined frequency; and   forming a compression/expansion wave determined by said actuator acoustic coupling and said predetermined frequency wherein fluid motion within said vessel is effected.   
   
   
       15 . The method according to  claim 14  wherein said predetermined frequency is in a range of from about 1 to 20 MHz. 
   
   
       16 . The method according to  claim 15  wherein said linear motor is a piezoelectric transducer. 
   
   
       17 . A porous material mixer comprising:
 a vessel for holding at least one porous material;   a plurality of actuator pairs, wherein each actuator pair comprises two member actuators and each actuator pair member is acoustically coupled with an opposing side of said vessel for generating a wave; and   at least one inlet in said vessel for admitting at least two fluids for combining, wherein said wave effects mixing of said at least two fluids.   
   
   
       18 . The mixer according to  claim 17  wherein each pair of actuators further comprises a linear motor wherein, when excited by a control signal, said motor exhibits an excursion. 
   
   
       19 . The mixer according to  claim 18  wherein said excursion applies a force against each actuator pair member. 
   
   
       20 . The mixer according to  claim 19  wherein said excursion and said actuator pair member acoustic coupling shapes said wave. 
   
   
       21 . The mixer according to  claim 20  wherein each actuator acoustic coupling is provided by at least two points separated by a predefined distance. 
   
   
       22 . The mixer according to  claim 21  wherein said force is coupled through said vessel wall into said at least one porous material. 
   
   
       23 . The mixer according to  claim 22  wherein each said actuator alternately applies force to each said point. 
   
   
       24 . The mixer according to  claim 23  wherein said linear motor is a piezoelectric transducer. 
   
   
       25 . The mixer according to  claim 24  wherein said control signal alternates at a frequency in a range of from about 1 to 20 MHz. 
   
   
       26 . The mixer according to  claim 25  wherein a difference between alternate force applications corresponds to about 180 degrees and generates a compression/expansion wave that corresponds with said alternate force applications. 
   
   
       27 . The mixer according to  claim 26  wherein said alternating force application of each actuator pair member is synchronized with its other pair member such that said compression/expansion wave generated by an actuator pair is reinforced. 
   
   
       28 . The mixer according to  claim 27  wherein each pair of said plurality of actuator pairs is in synchronism with each other and shares a common control signal. 
   
   
       29 . The mixer according to  claim 27  wherein each pair of said plurality of actuator pairs is not in synchronism with each other and does not share a common control signal. 
   
   
       30 . The mixer according to  claim 29  wherein each control signal for each actuator pair has a predetermined phase shift.