Water cooled heat exchanger for closed circuit wind tunnels - has grid of square air tubes and vertical coolant channels

摘要

The water-cooled heat exchanger for closed-circuit wind tunnels causes little pressure-loss and can take over the function of the usual grid to produce a laminar airflow. The cooler comprises a grid of vertical channels through which the cooling medium, e.g. water is made to flow. The medium is piped from a recirculating system external to the wind tunnel and enters the cooler at the top (2). Between the vertical columns are rows of square tubes (4) open at both ends and aligned with the axis of flow within the wind tunnel. The warm air flowing through the tubes loses heat through the thin tube walls to the medium circulating in the vertical channels. The coolant flows out of the exchanger through an outlet at the base (5).