HEAT EXCHANGER WITH MANIFOLDS FOR HEAT EXCHANGE

A heat exchanger is provided with a unitary, single-piece structure that can be formed via 3D printing, for example. The heat exchanger includes a main body a plurality of plates stacked and integrally formed with the body. First fluid channels are defined by gaps in the material of the main body, and second fluid channels are defined by gaps in the material of the main body and are stacked with the first fluid channels in alternating fashion, separated by the plates. Each of the first fluid channels are fluidly coupled to an inlet manifold and an outlet manifold. At least one of the manifolds is provided with surface features that improve heat exchange within the manifold. The surface features may be, for example, projections such as fins that increase surface area contact between the fluid in the manifold and the interior wall of the manifold.