Heat and energy exchange

Abstract

Materials, components, and methods are provided that are directed to the fabrication and use of micro-scale channels with a fluid for a heat exchange system, where the temperature and flow of the fluid is controlled, in part, through the macroscopic geometry of the micro-scale channel and the configuration of at least a portion of the wall of the micro-scale channel and the constituent particles that make up the fluid. Moreover, the wall of the micro-scale channel and the constituent particles are configured such that collisions between the constituent particles and the wall are substantially specular. Accelerating and decelerating elements provided herein can be configured with micro-scale channels which can trace out a generally spiral path.

1 - 70 . (canceled) 
     
     
         71 . An apparatus for heat exchange comprising:
 a micro channel comprising a wall portion; and   a gas comprising a constituent particle;   wherein the micro channel is configured to accommodate a flow of the gas in a first direction substantially perpendicular to a cross section of the micro channel; and   wherein the wall portion and the constituent particle are configured such that collisions between the constituent particle and the wall portion are substantially specular; and   wherein the wall portion comprises at least a first wall portion, a second wall portion, a third wall portion, a first intermediate wall portion, and a second intermediate wall portion;   wherein a boundary of the first wall portion is contiguous with a first boundary of the first intermediate wall portion, a first boundary of the second wall portion is contiguous with a second boundary of the first intermediate wall portion, a second boundary of the second wall portion is contiguous with a first boundary of the second intermediate wall portion, and a boundary of the third wall portion is contiguous with a second boundary of the second intermediate wall portion, such that the first wall portion, the first intermediate wall portion, the second wall portion, the second intermediate wall portion, and the third wall portion form a contiguous portion of the wall of the micro channel;   wherein a first normal to the first wall portion is not parallel to a second normal to the second wall portion, and is also not parallel to a third normal to the third wall portion, and where the second normal is also not parallel to the third normal;   wherein an angle offset between the first normal and the second normal is less than 90 degrees, and is approximately the same as an angle offset between the second normal and the third normal;   wherein a separation between the first wall portion and the second wall portion is at least an integer N times a largest width of the micro channel over that separation; and   wherein the angle offset between the first normal and the second normal is less than M degrees where M equals N/10.   
     
     
         72 . The apparatus of  claim 71 , wherein N is selected from at least one of: twenty-five and fifty. 
     
     
         73 . The apparatus of  claim 71 , wherein the gas comprises air. 
     
     
         74 . The apparatus of  claim 71 , wherein the micro channel is substantially confined to a planar region. 
     
     
         75 . The apparatus of  claim 71 , wherein a path of the micro channel is a spiral with an inner portion and an outer portion, wherein a radius if the outer portion is greater than a radius of the inner portion. 
     
     
         76 . The apparatus of  claim 71 , wherein at least a portion of the micro channel is configured with an internal surface area between approximately 3e-11 m̂2 per linear micron to 6e-10 m̂2 per linear micron. 
     
     
         77 . The apparatus of  claim 71 , wherein the wall portion further comprises a coating material deposited on a substrate. 
     
     
         78 . The apparatus of  claim 77 , wherein the substrate comprises copper. 
     
     
         79 . The apparatus of  claim 77 , wherein the coating material comprises tungsten. 
     
     
         80 . The apparatus of  claim 71 , wherein the wall portion is manufactured to be generally smooth. 
     
     
         81 . A method for heat exchange, comprising:
 providing a micro channel comprising a wall portion;   providing a gas comprising a constituent particle; and   inducing a flow of the gas adjacent to the wall portion;   wherein the micro channel is configured to accommodate the flow of the gas in a first direction substantially perpendicular to a cross section of the micro channel; and   wherein the wall portion and the constituent particle are configured such that collisions between the constituent particle and the wall portion are substantially specular; and   wherein the wall portion comprises at least a first wall portion, a second wall portion, a third wall portion, a first intermediate wall portion, and a second intermediate wall portion;   wherein a boundary of the first wall portion is contiguous with a first boundary of the first intermediate wall portion, a first boundary of the second wall portion is contiguous with a second boundary of the first intermediate wall portion, a second boundary of the second wall portion is contiguous with a first boundary of the second intermediate wall portion, and a boundary of the third wall portion is contiguous with a second boundary of the second intermediate wall portion, such that the first wall portion, the first intermediate wall portion, the second wall portion, the second intermediate wall portion, and the third wall portion form a contiguous portion of the wall of the micro channel;   wherein a first normal to the first wall portion is not parallel to a second normal to the second wall portion, and is also not parallel to a third normal to the third wall portion, and where the second normal is also not parallel to the third normal;   wherein an angle offset between the first normal and the second normal is less than 90 degrees, and is approximately the same as an angle offset between the second normal and the third normal;   wherein a separation between the first wall portion and the second wall portion is at least an integer N times a largest width of the micro channel over that separation; and   wherein the angle offset between the first normal and the second normal is less than M degrees where M equals N/10.   
     
     
         82 . The method of  claim 81 , wherein N is selected from at least one of:
 twenty-five and fifty.   
     
     
         83 . The method of  claim 81 , wherein:
 the step of providing a micro channel comprising a wall portion comprises:   providing the wall portion at a first temperature at a first time; and wherein a portion of the fluid flows through the micro channel during a period of time between the first time and a second time later than the first time; and
 wherein 
   the wall portion exhibits a second temperature that is less than the first temperature at the second time.   
     
     
         84 . The method of  claim 81 , wherein the gas comprises air. 
     
     
         85 . The method of  claim 81 , wherein a path of the micro channel is a spiral with an inner portion and an outer portion, where a radius if the outer portion is greater than a radius of the inner portion. 
     
     
         86 . The method of  claim 81 , further comprising, providing a heat exchange element conductively affixed to the wall portion. 
     
     
         87 . The method of  claim 81 , wherein at least a portion of the micro channel is configured with an internal surface area between approximately 3e-11 m̂2 per linear micron to 6e-10 m ̂2 per linear micron. 
     
     
         88 . The method of  claim 81 , wherein providing a micro channel comprising a wall portion further comprises: depositing a material on a surface of the micro channel using at least one of: sputtering and evaporative deposition. 
     
     
         89 . The method of  claim 88 , wherein the surface is copper. 
     
     
         90 . The method of  claim 88 , wherein the material is tungsten.