The heat exchanger assembly includes a first conduit, an external surface, and a set of fins. The first conduit includes a first inlet, a first outlet, and a first internal flow path extending between the first inlet and first outlet. The first conduit is configured to channel a flow of fluid to be cooled from the first inlet to the first outlet. The external surface which includes a plurality of regions. Each region of the plurality of regions includes a respective set of fins extending from the external surface. Each set of fins of a respective region of the plurality of regions are oriented in a different direction than sets of fins of other regions of the plurality of regions.