Blow Down Wind Tunnels are a special type of Open Circuit wind tunnel. For Blow Down Wind Tunnels, however, air is blown down into the wind tunnel by a fan located upstream of the test section, as the name implies. Compared to standard Open Circuit wind tunnel configuration, blow-down style tunnels provide an extra degree of testing flexibility. For most Open Circuit tunnels, fan assemblies are located downstream of the test section and air is drawn through the wind tunnel with suction. Most commonly, these tunnels are used for tests requiring liquid or particulate injection. All blow-down style tunnels have custom test sections, and many are requested to include built-in test article mounting arrangements. Because all tunnels are made to fit the customers needs, there is no limitation to the options available.
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