An apparatus is provided. The apparatus includes a plurality of flow guiding structures spatially aligned in a first row, each of the plurality of flow guiding structures comprising a fin-shape to funnel airflow at a trailing edge of each of the plurality of flow guiding structures. The apparatus also includes a plurality of flow separating structures spatially aligned in a second row interleaved between each of the plurality of flow guiding structures, each of the plurality of flow separating structures comprising a fin-shape configured to split airflow received from the plurality of flow guiding structures.