A ram air system includes a bay comprising an exterior wall defining an interior volume that at least partially encloses a ram air duct. The ram air duct includes an outlet configured to discharge an exhaust airflow at a first temperature. At least one of the exterior wall and the ram air duct defines an aperture therein providing for flow communication between the bay interior volume and the exhaust airflow such that cooling air flows from the interior volume to form a boundary layer between the exhaust airflow and the exterior wall downstream of the outlet. The boundary layer is at a second temperature that is lower than the first temperature.