| CPC F28F 21/04 (2013.01) [C03B 19/025 (2013.01); C03B 19/063 (2013.01); C03C 14/002 (2013.01); C03C 2214/02 (2013.01); C03C 2214/20 (2013.01); C03C 2214/30 (2013.01); C03C 2214/34 (2013.01)] | 9 Claims | 

| 
               1. A heat exchanger comprising: 
            one or more tubular regions, wherein each tubular region of the one or more tubular regions comprises: 
                a passage defining a radially inner surface of the one or more tubular regions; and 
                  a radially outer surface; 
                one or more reinforcing fibers between the radially inner surface and the radially outer surface of each tubular region; 
                a glass matrix material infiltrating the one or more reinforcing fibers; 
                one or more flat regions between each of the one or more tubular regions; 
                a first pattern formed into the radially inner surface of each tubular region; and 
                a second pattern formed into the radially outer surface of each tubular region. 
               |