An apparatus for controlling airflow in a duct of an aircraft galley chiller includes first and second legs having ends connected together to form a vane, and free ends configured to be attached within the duct. A free end of one first leg may have a beveled edge, and the free end of the other leg may have a flat edge, and each leg may have one or more score lines to aid cutting lengths of the first and second legs. The legs are connected together at a predetermined fixed angle, or at an adjustable angle, such as by an adjustable hinge. A pair of opposing vanes may be attached within opposing sides of the duct to form a venturi within the duct.