Structural Cooldown Energy Optimization for Cryogenic Wind Tunnels
High Reynolds number cryogenic nitrogen tunnels usually have considerable mass of structural metal within the insulated test environment. Prior to high Reynolds number aerodynamic testing, this internal structure is cooled from ambient temperature to 120K using liquid nitrogen. This paper studies the structural cooldown as a problem of optimizing liquid nitrogen consumption and time for the U.S National Transonic Facility. A simple model of the tunnel thermodynamic process is used to study the optimization and cooldown strategies via nonlinear dynamical simulation.
KeywordsMach Number Test Section Inlet Guide Vane Tunnel Pressure Tunnel Flow
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