Design of Integrated Heat Exchanger into Solar Absorber for Affordable Small-scale Concentrated Solar Power Generation (SCU)

Abstract

A solar absorber for a concentrated solar power (CSP) dish system includes a cylindrically shaped blackbody cavity receiver fused to a cylindrically shaped heat exchanger shell covering the receiver to form a monolithic cavity receiver and heat exchanger. An exterior surface of the cavity receiver has grooves embedded to create a duct spiraling about the exterior of the cavity receiver so that the duct forms tubes of a tube-style heat exchanger when covered by the heat exchanger shell. An interior diameter of the cavity receiver is greater than or equal to a diameter of an aperture of the cavity receiver, and a longitudinal interior depth of the cavity is greater than or equal to twice the interior diameter of the cavity receiver. The monolithic solar absorber is preferably composed of a ceramic material such as silicon carbide having emissivity greater than 0.9.

1 . A solar absorber for a concentrated solar power (CSP) dish system, the solar absorber comprising:
 a) a cylindrically shaped blackbody cavity receiver,   wherein an exterior surface of the cavity receiver has grooves embedded to create a duct spiraling about the exterior of the cavity receiver,   wherein an interior diameter of the cavity receiver is greater than or equal to a diameter of an aperture of the cavity receiver,   wherein a longitudinal interior depth of the cavity is greater than or equal to twice the interior diameter of the cavity receiver,   wherein the cavity receiver is composed of a first monolithic ceramic material having emissivity greater than 0.9;   and   b) a cylindrically heat exchanger shell covering the receiver such that the duct forms tubes of a tube-style heat exchanger,   wherein the heat exchanger shell is composed of a second monolithic ceramic material having emissivity greater than 0.9;   wherein the cavity receiver and heat exchanger shell are fused to form a monolithic cavity receiver and heat exchanger.   
     
     
         2 . The solar absorber of  claim 1  wherein the first monolithic ceramic material is silicon carbide. 
     
     
         3 . The solar absorber of  claim 2  wherein the interior diameter of the cavity receiver is equal to the diameter of the aperture of the cavity receiver. 
     
     
         4 . The solar absorber of  claim 1  wherein the first monolithic ceramic material is silicon nitride. 
     
     
         5 . The solar absorber of  claim 1  wherein the duct has a rectangular cross-section.