Microscale heat or heat and mass transfer system

Abstract

Microscale, monolithic heat or heat and mass transfer systems: a plurality of shims ( 102, 104 ) assembled between two outer plates ( 110, 111 ) that, when combined, form discrete but integrated heat and mass transfer system components that make up a microscale, monolithic absorption cooling and/or heating system, or other heat or heat and mass transfer system. The shims generally include a plurality of microchannels ( 702 ), voids, fluid passages, and other features for transferring fluids between defined components throughout the system, and into and out of the system to and from heating and cooling sources and sinks as needed. Generally, two distinct shim types are used and combined together as a plurality of shim pairs to enable thermal contact between the fluids flowing within the microchannels in each shim pair, each shim in each shim pair comprising slightly different microchannel and fluid passage arrangements as compared to each other.

1 - 214 . (canceled) 
     
     
         215 . An integrated heat and mass transfer apparatus comprising:
 a heat and mass transfer system having at least one heat exchange region for affecting a heat transfer function of a particular component;   a fluid coupling means for coupling a thermally modified flow of a coupling fluid through the at least one heat exchange region; and   a pair of cover plates that include ports for introducing a working fluid and the coupling fluid into functional components and for transporting the working fluid and the coupling fluid out of the functional components;   wherein the at least one heat exchange region defined by a plurality of rows of microchannels of a plurality of shims, the shims being stacked, planar, and heat conducting shims, each shim comprising:
 openings that define a plurality of fluid voids for containing:
 the working fluid; and 
 the coupling fluid for conveying thermal energy into or out of the heat and mass transfer system; 
 
 the plurality of rows of microchannels being formed by microscale indentations on the plurality of shims; 
   wherein the plurality of rows of microchannels comprise:
 a first row of microchannels for communicating a first flow of the working fluid from an inlet fluid void associated with the particular component of the heat and mass transfer system into an outlet fluid void associated with the particular component of the heat and mass transfer system; and 
 a second row of microchannels for communicating either a second flow of the working fluid associated with the particular component of the heat and mass transfer system or a flow of the coupling fluid for the heat transfer function of the heat exchange regions, wherein the second row of microchannels are in thermal contact with the first row of microchannels to conduct heat between the first flow of the working fluid in the first row of microchannels and either the second flow of the working fluid or the flow of the coupling fluid in the second row of microchannels for the heat transfer function of the at least one heat exchange region; and 
   wherein the system provides a heating or cooling function via the thermally modified flow of the coupling fluid.   
     
     
         216 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the system is configured to operate as a heat pump, wherein the fluid coupling means comprises:
 a first fluid coupling means for coupling a first flow of a heated coupling fluid through a an initial stage heat exchange region of the heat and mass transfer system for receiving thermal energy into the system;   a second fluid coupling means for coupling a thermally modified second flow of coupling fluid through a subsequent stage heat exchange region of the heat and mass transfer system; and   a third fluid coupling means for coupling a heat rejection flow of coupling fluid through a heat exchange region of a stage of the heat and mass transfer system.   
     
     
         217 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the plurality of shims are arranged as a plurality of pairs of shims of a first type and a second type that when paired together define the microchannels for communicating working fluid and/or coupling fluid between fluid voids of the particular component of the heat and mass transfer system. 
     
     
         218 . The integrated heat and mass transfer apparatus of  claim 217 , wherein each of the pairs of shims comprise a predetermined single element of a multi-element array of the shims that have dimensions determined by input/output thermal properties and fluid flow characteristics of the heat and mass transfer system. 
     
     
         219 . The integrated heat and mass transfer system of apparatus  215 , wherein the particular component of the heat and mass transfer system comprises a refrigerant absorber, wherein a plurality of vapor inlet holes formed in a row of the microchannels on a first shim provide for vapor flowing from a passage in an adjacent second shim to flow into the microchannels of the first shim and mix with absorbent in the microchannels of the first shim. 
     
     
         220 . The integrated heat and mass transfer apparatus of  claim 215 , wherein one of the plurality fluid voids comprises a fluid header for directing a flow of working fluid or coupling fluid for the particular component into a fluid distribution passage that directs the fluid into a row of microchannels. 
     
     
         221 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the microscale indentations comprise a shape formed in a top surface of a first shim of one of the plurality of shims for conducting fluid alongside and thermal energy into a corresponding and adjacent bottom surface of an adjacent second shim of the plurality of shims that encloses the indentations so as to form the microchannels. 
     
     
         222 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the microscale indentations are selected from the group consisting of machined grooves, cut grooves, photoetched grooves, chemically etched grooves, laser etched grooves, molded grooves, stamped grooves, and particle blasted grooves. 
     
     
         223 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the plurality of stacked shims and pair of cover plates are physically bonded to form a unitary structure. 
     
     
         224 . The integrated heat and mass transfer apparatus of  claim 223 , wherein the physical bonding is performed by a method selected from the group consisting of diffusion bonding, gluing, brazing, welding, and pressing. 
     
     
         225 . The integrated heat and mass transfer apparatus of  claim 215 , wherein a particular implementation of the heat and mass transfer system comprises an absorption heat pump with the working fluid of the absorption heat pump being selected from the group consisting of ammonia-water and lithium-bromide-water admixture. 
     
     
         226 . The integrated heat and mass transfer apparatus of  claim 225 , wherein the heat pump is configured to be a single-effect, a double-effect, a triple-effect, or a generator-absorber-heat exchange (GAX) cycle. 
     
     
         227 . The integrated heat and mass transfer apparatus of  claim 215 , further comprising one or more fluid pumps for moving the working fluid or the coupling fluid between the functional components. 
     
     
         228 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the flow of working fluid in the first row of microchannels is substantially counterflow, parallel-flow, co-flow or crossflow in direction to the direction of flow of fluid in the second row of microchannels. 
     
     
         229 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the particular component of the heat and mass transfer system comprises a refrigerant rectifier of an absorption heat pump, and further comprises a plurality of fluid-retaining ribs formed within the monolithic support structure that form trays for containing a quantity of liquid and enable a flow of vapor and liquid in opposite directions, with the fluid and vapor in direct mass contact across a surface of liquid contained by the trays and in thermal contact with a coupling fluid or working fluid, with a reflux of liquid collecting and exiting the rectifier in a generally downward fashion to join a desorber solution flow. 
     
     
         230 . The integrated heat and mass transfer apparatus of  claim 215 , wherein the heat and mass transfer system is an absorption heat pump or a multi-component fluid processing system that includes a forced convective flow of fluids in some regions within the system and a gravity/buoyancy driven flow of fluids in other regions of the system such that desired liquid or vapor temperatures, species concentrations, and species concentration gradients during phase change are achieved, and further comprising passages formed within the monolithic structure that provide for downward liquid flow in conjunction with upward vapor flow in a counterflow arrangement within the passages, whereby conditions promoting the boiling or desorption of vapor and/or higher refrigerant vapor purities are effected. 
     
     
         231 . A heat and mass transfer apparatus configured for use in a heat and mass transfer system, the apparatus comprising:
 a pair of cover plates that include ports for introducing a working fluid and a coupling fluid into a plurality of functional components within a support structure and for transporting the working fluid and the coupling fluid out of at least one of the plurality of functional components   a plurality of shim pairs bonded to the pair of cover plates to form an integrated heat and mass transfer system, the plurality of shim pairs comprising a plurality of openings defining a plurality of fluid voids and having microscale indentations formed in a surface of the shim pairs defining a first row of microchannels and a second row of microchannels; and   a fluid coupling means for coupling a thermally modified flow of coupling fluid through a heat exchange region of a stage of the heat and mass transfer apparatus, whereby the apparatus provides a heating or cooling function via the thermally modified flow of coupling fluid as appropriate for the heat and mass transfer system.   
     
     
         232 . The heat and mass transfer apparatus of  claim 231 , wherein the plurality of fluid voids contain the working fluid and the coupling fluid employed for conveying thermal energy into or out of the support structure, wherein the plurality of voids define one or more integrally formed heat exchange regions defined and contained within the support structure for effecting a heat transfer function of at least one of the plurality of functional components of the heat and mass transfer system. 
     
     
         233 . The heat and mass transfer apparatus of  claim 232 , wherein each heat exchange region comprises:
 the first row of microchannels defined in the thermally conducting material for communicating a first flow of the working fluid from an inlet fluid void associated with a first functional component of the plurality of functional components of the particular heat and mass transfer system into an outlet fluid void associated with a second functional component of the plurality of functional components of the heat and mass transfer system; and   the second row of microchannels defined in the thermally conducting material for communicating either a second flow of working fluid associated with the first functional component of the plurality of functional components of the heat and mass transfer system or a flow of the coupling fluid for the particular heat transfer function of the heat exchange region.   
     
     
         234 . The heat and mass transfer apparatus of  claim 233 , wherein the first row of microchannels and the second row of microchannels are arranged in thermal contact with each other within the support structure so as to conduct heat between the first flow of working fluid in the first row of microchannels and either the second flow of working fluid or the flow of coupling fluid in the second row of microchannels. 
     
     
         235 . The heat and mass transfer apparatus of  claim 231 , wherein the flow of the working fluid in the first row of microchannels is substantially counterflow, parallel-flow, co-flow or crossflow in direction to the direction of flow of fluid in the second row of microchannels. 
     
     
         236 . The heat and mass transfer apparatus of  claim 231 , wherein the system is a heat pump, and wherein the fluid coupling means comprises:
 a first fluid coupling means for coupling a first flow of a heated coupling fluid through a heat exchange region defining an initial stage of the heat and mass transfer system for receiving thermal energy into the heat and mass transfer system;   a second fluid coupling means for coupling a thermally modified second flow of coupling fluid through a heat exchange region defining a subsequent stage of the heat and mass transfer system; and   a third fluid coupling means for coupling a heat rejection flow of coupling fluid through a heat exchange region of a stage of the heat and mass transfer system, whereby the system provides a heating or cooling function via the thermally modified second flow of coupling fluid for the heat and mass transfer system and a heat rejection function via the heat rejection flow of coupling fluid.   
     
     
         237 . The heat and mass transfer apparatus of  claim 231 , wherein each of the plurality of pair of shims comprises a predetermined single element of a multi-element array of the shims, the multi-element array having dimensions determined by the input/output thermal properties and fluid flow characteristics of the heat and mass transfer system. 
     
     
         238 . The heat and mass transfer apparatus of  claim 231 , wherein one of the fluid voids comprises a fluid header formed within the support structure for directing a flow of working fluid or coupling fluid into a fluid distribution passage that directs the fluid into a row of microchannels. 
     
     
         239 . The heat and mass transfer apparatus of  claim 238 , wherein the fluid header comprises a region within the plurality of shim pairs defining:
 an opening for receiving fluid; and   a fluid void defined by the plurality of shim pairs within the fluid header;   and a fluid distribution passage defined in alternating shims of at least one of the shims in the plurality of shim pairs.   
     
     
         240 . The heat and mass transfer apparatus of  claim 231 , wherein the microscale indentations comprise a shape formed in a top surface of a first shim of one of the shims in a pair of the plurality of shim pairs for conducting fluid alongside and thermal energy into a corresponding and adjacent bottom surface of an adjacent second shim that encloses the indentations so as to form the microchannels. 
     
     
         241 . The heat and mass transfer apparatus of  claim 231 , wherein the microscale indentations are selected from the group consisting of machined slots, machined grooves, cut grooves, photoetched grooves, chemically etched grooves, laser etched grooves, molded grooves, stamped grooves, and particle blasted grooves, or combinations thereof. 
     
     
         242 . The heat and mass transfer apparatus of  claim 231 , wherein the working fluid is selected from the group consisting of ammonia-water and lithium-bromide-water admixture. 
     
     
         243 . The heat and mass transfer apparatus of  claim 231 , wherein the system is a heat pump configured for operation selected from the group consisting of a single-effect, double-effect, a triple-effect, and a generator-absorber-heat exchange (GAX) cycle. 
     
     
         244 . The heat and mass transfer apparatus of  claim 231 , further comprising one or more fluid pumps for moving the working fluid or the coupling fluid between components.