Heat exchanger for a gas turbine engine

Abstract

A heat exchanger apparatus for a gas turbine engine includes: a plurality of heat exchanger pipes, each pipe having first and second ends; wherein the heat exchanger pipes are disposed in a repeating pattern such that each heat exchanger pipe is joined to at least one other heat exchanger pipe.

What is claimed is: 
     
         1 . A heat exchanger apparatus for a gas turbine engine, comprising a plurality of heat exchanger pipes, each pipe having first and second ends; wherein the heat exchanger pipes are disposed in a repeating pattern such that each heat exchanger pipe is joined to at least one other heat exchanger pipe. 
     
     
         2 . The apparatus of  claim 1  wherein each heat exchanger pipe is joined to other heat exchanger pipes at two or more locations. 
     
     
         3 . The apparatus of  claim 1  wherein each heat exchanger pipe is joined to other heat exchanger pipes at three locations. 
     
     
         4 . The apparatus of  claim 1  wherein the joints between neighboring heat exchanger pipes are defined by mutually shared wall portions of the heat exchanger pipes. 
     
     
         5 . The apparatus of  claim 1  further comprising a fluid manifold, wherein the first and second ends of each heat exchanger pipe are connected in fluid communication with the fluid manifold. 
     
     
         6 . The apparatus of  claim 5  wherein the fluid manifold includes at least one inlet channel and at least one outlet channel, and the first end of each heat exchanger pipe is connected to an inlet channel and the second end of each heat exchanger pipe is connected to an outlet channel. 
     
     
         7 . The apparatus of  claim 5  wherein:
 the inlet and outlet channels are spaced-apart from each other; 
 each heat exchanger pipe has a shallow S shape with first and second ends; 
 the first end of each heat exchanger pipe is connected to the inlet channel; and 
 the second end of each heat exchanger pipe is connected to the outlet channel. 
 
     
     
         8 . The apparatus of  claim 7  wherein each heat exchanger pipe includes a straight central portion and first and second end bends that are curved opposite each other. 
     
     
         9 . The apparatus of  claim 7  wherein tire heat exchanger pipes are grouped in pairs, each pair of heat exchanger pipes being mutually joined and forming an X shape. 
     
     
         10 . The apparatus of  claim 1  wherein each heat exchanger pipe has at least one bend therein. 
     
     
         11 . The apparatus of  claim 1  wherein each heat exchanger pipe has a shape including two spaced-apart, parallel legs interconnected by a transverse bridge. 
     
     
         12 . The apparatus of  claim 11  wherein each leg includes a first upright segment, an axial segment, and a second upright segment. 
     
     
         13 . The apparatus of  claim 12  wherein the bridge of each heat exchanger pipe is joined to the leg of a neighboring heat exchanger pipe. 
     
     
         14 . The apparatus of  claim 11  wherein the heat exchanger pipes are arranged in two spaced-apart rows, wherein the heat exchanger pipes of the rows are disposed mirror-images acute angles to a reference axis. 
     
     
         15 . The apparatus of  claim 13  wherein the heat exchanger pipes of the first row are interlocked with the heat exchanger pipes of the second row. 
     
     
         16 . The apparatus of  claim 1  wherein an exterior surface of at least one of the heat exchanger pipes includes an area-increasing structure. 
     
     
         17 . The apparatus of  claim 16  wherein the area-increasing structure is made from a material different from the at least one heat exchanger pipe. 
     
     
         18 . The apparatus of  claim 1  wherein flow channels defined between the heat exchanger pipes having an approximately constant flow area along a selected direction of flow.