Heat exchangers containing carbon nanotubes and methods for the manufacture thereof

Abstract

Vehicular radiators and other heat exchangers containing carbon nanotubes (CNTs) are provided, as are methods for manufacturing nanotube heat exchangers. In one embodiment, the nanotube heat exchanger includes a coolant flow passage, an airflow path, a heat exchanger core bounding at least a portion of the coolant flow passage and the airflow path. The heat exchanger core contains a plurality of CNTs configured to enhance heat transfer from a coolant conducted through the coolant flow passage to airflow directed along the airflow path during operation of the nanotube heat exchanger. The CNTs can be, for example, single walled CNTs or other CNTs incorporated into one or more regions of the heat exchanger core by applying a nanotube coating to selected surfaces of the heat exchanger core or by producing the heat exchanger core to include one or more sintered, CNT-containing components.

What is claimed is: 
     
         1 . A nanotube heat exchanger, comprising:
 a coolant flow passage;   an airflow path; and   a heat exchanger core bounding at least a portion of the coolant flow passage and the airflow path, the heat exchanger core containing a plurality of Carbon Nanotubes (CNTs) through which heat is transferred from a coolant conducted through the coolant flow passage to airflow directed along the airflow path during operation of the nanotube heat exchanger.   
     
     
         2 . The nanotube heat exchanger of  claim 1  further comprising a nanotube coating applied to a surface of the heat exchanger core and containing the plurality of CNTs. 
     
     
         3 . The nanotube heat exchanger of  claim 2  wherein the nanotube coating comprises:
 a surface contacted by airflow directed along the airflow path; and 
 a directional CNT array containing the plurality of CNTs, which are oriented to extend substantially perpendicular to a primary direction of airflow along the airflow path. 
 
     
     
         4 . The nanotube heat exchanger of  claim 2  wherein the nanotube coating comprises:
 an outer surface contacted by coolant flowing through the coolant flow passage; and 
 a directional CNT array containing the plurality of CNTs, which are oriented to extend substantially parallel to a primary direction of coolant flow through the coolant flow passage. 
 
     
     
         5 . The nanotube heat exchanger of  claim 2  wherein the heat exchanger core comprises a coolant-conducting tube through which the coolant flow passage extends and to which the nanotube coating is applied. 
     
     
         6 . The nanotube heat exchanger of  claim 2  wherein the heat exchanger core comprises:
 a coolant-conducting tube through which the coolant flow passage extends; and 
 an in-tube structure mounted within the coolant-conducting tube and having a surface to which the nanotube coating is applied. 
 
     
     
         7 . The nanotube heat exchanger of  claim 2  wherein the nanotube coating comprises a fluid-contacted surface having a non-planar topology. 
     
     
         8 . The nanotube heat exchanger of  claim 2  wherein the heat exchanger core comprises:
 a coolant-conducting tube through which the coolant flow passage extends; and 
 a fin structure adjacent the coolant-conducting tube, at least a portion of the nanotube coating located between the coolant-conducting tube and the fin structure such that heat conductively transferred from the coolant-conducting tube to the fin structure passes through the nanotube coating. 
 
     
     
         9 . The nanotube heat exchanger of  claim 1  wherein the heat exchanger core comprises a radiator component in which the plurality of CNTs is embedded. 
     
     
         10 . The nanotube heat exchanger of  claim 9  wherein the radiator component is selected from the group consisting of a coolant-conducting tube, a fin structure, and in-tube structure, and an end tank. 
     
     
         11 . The nanotube heat exchanger of  claim 1  wherein the plurality of CNTs comprises a plurality of single walled CNTs arranged in an array. 
     
     
         12 . A nanotube heat exchanger promoting heat transfer from a coolant circulated through the nanotube heat exchanger to airflow contacting one or more surfaces of the nanotube heat exchanger, the nanotube heat exchanger comprising:
 a coolant-conducting tube; and   a first Carbon Nanotube (CNT)-containing structure located within the coolant-conducting tube, the first CNT-containing contacted by the coolant flowing through the coolant-conducting tube to promote heat transfer from the coolant to the airflow contacting the one or more surfaces of the nanotube heat exchanger.   
     
     
         13 . The nanotube heat exchanger of  claim 12  wherein the coolant-conducting tube comprises an inner surface, and wherein the first CNT-containing structure comprises a nanotube coating applied to the inner surface of the coolant-conducting tube. 
     
     
         14 . The nanotube heat exchanger of  claim 13  wherein the nanotube coating comprises an anisotropic CNT array oriented to extend, at least in substantial part, along the length of the coolant-conducting tube. 
     
     
         15 . The nanotube heat exchanger of  claim 12  further comprising an in-tube structure mounted within the coolant-conducting tube, and wherein the first CNT-containing structure comprises a nanotube coating applied to a surface of the in-tube structure. 
     
     
         16 . The nanotube heat exchanger of  claim 12  further comprising:
 a fin structure adjacent the coolant-conducting tube; and 
 a second CNT-containing structure disposed between the fin structure and the coolant-conducting tube, as taken along a thermal transfer path extending from an interior surface of the coolant-conducting tube to an exterior surface of the fin structure. 
 
     
     
         17 . The nanotube heat exchanger of  claim 12  wherein the first CNT-containing structure comprises a sintered component in which a plurality of CNTs is embedded. 
     
     
         18 . The nanotube heat exchanger of  claim 12  further comprising an end tank fluidly coupled to the coolant-conducting tube, the end tank comprising a sintered, CNT-containing body. 
     
     
         19 . A method for manufacturing a nanotube heat exchanger, comprising:
 producing a heat exchanger core having a plurality of air-contacted surfaces and plurality of coolant-contacted surfaces; and   integrating Carbon Nanotubes (CNTs) into one or more regions of the heat exchanger core thermally coupled between the plurality of air-contacted surfaces and the plurality of coolant-contacted surfaces.   
     
     
         20 . The method of  claim 19  wherein integrating the CNTs into one or more regions of the heat exchanger core comprises applying a nanotube coating to selected surfaces of the heat exchanger core.