Passive thermoacoustic cooling apparatus

Abstract

A passive thermoacoustic cooling apparatus for cooling of components such as miniaturized microelectronics is disclosed. The passive thermoacoustic cooling apparatus includes resonant cavities, a temperature-difference element and a heat conduction element. The temperature-difference element is integrated with the system of resonant cavities for conversion of heat into acoustic power. The heat conducting element connects a heat source to the temperature-difference element, which transmits heat from the source to one end of the temperature-difference component. Due to established temperature gradient across hot and cold ends of the temperature-difference element, acoustic standing wave arises in the resonant cavity system. Forced air convection is thereby generated to cool the heat source.

1 . A thermoacoustic heat dissipation apparatus for passive cooling of a heat source, said apparatus operating solely on said heat source to be cooled without any additional energy source, said apparatus comprising: 
 at least one temperature difference element having a hot end and a cold end;    a heat conduction element connected to said hot end of said temperature difference element and to said heat source for conduction of heat from said heat source to said temperature difference element; and    at least one cavity casing defining a resonance cavity therein and internally enclosing said temperature difference element and said heat conduction element; wherein    said temperature difference element being positioned inside said resonance cavity at a location sustaining a thermoacoustic effect by the generation of a standing wave therein;    said cold end of said temperature difference element facing toward an open end of said resonance cavity; and    said temperature difference element having an air-passing porous body structure allowing connectivity between the air at the hot and cold ends thereof inside said resonance cavity.    
   
   
       2 . The apparatus of  claim 1  wherein said heat source to be cooled encloses the end of said resonance cavity opposite to said open end of said resonance cavity.  
   
   
       3 . The apparatus of  claim 1  wherein said temperature difference element is made of a material with low thermal conductivity coefficient to be optimized for preventing heat conduction and said heat conduction element is made of a material with high thermal conductivity coefficient optimized for heat conduction.  
   
   
       4 . A thermoacoustic heat dissipation apparatus for passive cooling of a heat source, said apparatus operating solely on said heat source to be cooled without any additional energy source, said apparatus comprising: 
 at least one temperature difference element having a hot end and a cold end;    a heat conduction element connected to said hot end of said temperature difference element and to said heat source for conduction of heat from said heat source to said temperature difference element; and    at least one cavity casing defining a resonance cavity therein and internally enclosing said temperature difference element and said heat conduction element; wherein    said temperature difference element being positioned inside said resonance cavity at a location sustaining a thermoacoustic effect by the generation of a standing wave therein;    said cold end of said temperature difference element facing toward an open end of said resonance cavity;    said temperature difference element having an air-passing porous body structure allowing connectivity between the air at the hot and cold ends thereof inside said resonance cavity; and    said heat source to be cooled enclosing the end of said resonance cavity opposite to said open end of said resonance cavity.    
   
   
       5 . The apparatus of  claim 4  wherein said temperature difference element is made of a material with low thermal conductivity coefficient to be optimized for preventing heat conduction and said heat conduction element is made of a material with high thermal conductivity coefficient optimized for heat conduction.  
   
   
       6 . The apparatus of  claim 4  wherein said heat conduction element is configured to constitute a portion of said resonance cavity at the end opposite to said open end of said resonance cavity.  
   
   
       7 . A thermoacoustic heat dissipation apparatus for passive cooling of a heat source, said apparatus operating solely on said heat source to be cooled without any additional energy source, said apparatus comprising: 
 at least one temperature difference element having a hot end and a cold end;    a heat conduction element connected to said hot end of said temperature difference element and to said heat source for conduction of heat from said heat source to said temperature difference element; and    a resonance cavity system comprising an aggregation of a plurality of cavity casings each defining a resonance cavity therein, said resonance cavity system internally enclosing and embedding said temperature difference element and said heat conduction element; wherein    said temperature difference element being positioned inside each of said resonance cavities at a location sustaining a thermoacoustic effect by the generation of a standing wave therein; and    said temperature difference element having an air-passing porous body structure allowing connectivity between the air at the hot and cold ends thereof inside said resonance cavity.    
   
   
       8 . The apparatus of  claim 7  wherein said temperature difference element is made of a material with low thermal conductivity coefficient to be optimized for preventing heat conduction and said heat conduction element is made of a material with high thermal conductivity coefficient optimized for heat conduction.  
   
   
       9 . The apparatus of  claim 7  wherein said aggregation of said resonance cavity system is a vertical stacking of a plurality of individual resonance cavities.  
   
   
       10 . The apparatus of  claim 7  wherein said aggregation of said resonance cavity system is a horizontal expansion of a plurality of individual resonance cavities.  
   
   
       11 . The apparatus of  claim 7  wherein said heat conduction element is configured to constitute a portion of said resonance cavity system at the end opposite to said open end of said resonance cavities.