Wind tunnel is a test facility used to simulate the flight conditions. It allows us to make a reusable prototype and test it in the tunnel in low cost. Hypersonic wind tunnels operate at hypersonic speeds ie, with a mach number greater than 6. For doing experiments, it is necessary to maintain a constant pressure in the settling chamber of the tunnel so that we get the desired mach number and mass flow rate at the nozzle output. Here, a PI controller with anti reset wind up is designed and the pressure of hypersonic intermittent blow down type wind tunnel is controlled.

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Hypersonic wind tunnel PI controller Anti reset wind up Servo operation Regulator operation